NSW Seasonal Conditions Report - April 2015 · Outlook information was up to date as at 17 April...

The seasonal outlooks presented in this report are obtained from the Australian Bureau of Meteorology and other sources. These outlooks are general statements about the likelihood (chance) of (for example) exceeding the median rainfall or minimum or maximum temperatures. Such probability

outlooks should not be used as categorical or definitive forecasts, but should be regarded as tools to assist in risk management and decision making. Changes in seasonal outlooks may have occurred since this report was released. Outlook information was up to date as at 17 April 2015.

NSW Seasonal Conditions Report - April 2015Highlights • March rainfall was below average across 72% of NSW. • Wetter than normal conditions are likely between April

and June across most of NSW. Warmer overnight temperatures are likely, and warmer daytime temperatures in the east.

• ENSO is neutral, although warming has continued in the equatorial Pacific. El Niño thresholds are likely to be met in April/May. NOAA suggest a weak El Niño has started.

• Topsoil moisture levels were low in western and central NSW. Subsoil moisture levels were generally stable.

• Pasture growth declined over most of NSW except the north coast.

• Forage crops have responded to March/April rain and further sowings were made. Winter crop sowing is under way. Wet conditions have delayed cotton harvesting.

• Resources to assist in management for areas suffering poor rainfall and growth are available at www.dpi.nsw.gov.au/agriculture/emergency/drought/managing

1. Summary Rainfall during March was below average across 72% of NSW, and average across 22%. Rainfall was below average over much of western, southern, central and south eastern NSW, and in areas of the north west. Areas of the northern slopes and plains, northern tablelands, the Hunter valley and the north of the central tablelands received average rainfall. Good rainfall during early-mid April occurred across eastern, central and southern NSW.

Pasture growth declined across most of NSW during March. Growth slowed across the south of the northern tablelands and over the south and central coast. It remained reasonable across areas of the north and mid-north coast. Relative to historical records, growth was below average across western, central and south eastern NSW but near average across much of the tablelands, northern slopes and mid-north to north coast.

Biomass levels declined across most of NSW, particularly across central NSW and areas of the west. Supplementary feeding of stock increased in March, but April rainfall has eased conditions.

Winter forage crops have benefited from the rainfall. The early April rainfall stimulated additional sowings. Prospects for winter crops have improved in most areas except areas of the north west (west of the Newell Highway) and early sowings have commenced. Wet conditions have delayed cotton harvesting.

Wetter than normal conditions are likely across most of NSW between April and June. Warmer than normal daytime temperatures are likely across the coast, tablelands and areas of the slopes and eastern plains of NSW. Overnight temperatures are likely to be warmer. During April, wetter than normal conditions are likely across western, southern and central NSW. ENSO is neutral, but sea surface temperatures are warm across most of the equatorial Pacific. The Bureau of Meteorology suggests warming to above El Niño thresholds is likely in April-May and the ENSO tracker is at ‘El Niño Alert’. NOAA considers a weak event started in February. Rainfall across NSW was between 0-300 mm during March, and was concentrated in the east. Western NSW and areas of the north west received 0-10 mm. Temperatures were slightly warmer. Relative quarterly rainfall was average over 69% of the State. Half yearly relative rainfall was average over 64% of NSW. Modelled topsoil moisture levels were low across most of NSW except over the mid-north to north coast. Subsoil moisture levels were relatively stable, but low in areas of the north and west.

Yearly runoff was below average over areas of northern and central NSW, the tablelands, Hunter valley, Sydney basin and Riverina. Stock water supplies are low in many areas.

Relative pasture growth was below average across western, central and south eastern NSW. It was near average across the tablelands, northern slopes and mid-north to north coast.

Relative biomass levels were low over north western and central NSW. They were average in the west and average to above average in the east, tablelands and areas of the far west.

http://www.dpi.nsw.gov.au/agriculture/emergency/drought/managing

NSW Seasonal Conditions Report - April 2015

2 NSW Department of Primary Industries, April 2015

Table of Contents

Highlights 1

1. Summary 1

2. Seasonal outlook 3

2.1 Seasonal outlook summary 3

2.2 Seasonal rainfall outlook 3

2.3 Seasonal temperature outlook 3

2.4 Monthly rainfall and temperature outlook 4

2.5 Other climatic models 5

2.6 El Niño-Southern Oscillation (ENSO) 5

2.7 Other climatic indicators 10

3. Rainfall 10

3.1 Relative rainfall 10

3.2 Total rainfall 11

4. Temperature anomalies 12

5. Relative soil moisture 12

5.1 Summary 12

5.2 Topsoil 12

5.3 Subsoil 13

6. Pasture growth and biomass 13

6.1 Pasture growth outlook 13

6.2 Modelled pasture growth 14

6.2 Modelled biomass 14

6.4 Relative pasture growth 14

6.5 Relative biomass 16

7. Streamflow, water storage and irrigation allocations 16

7.1 Streamflow 16

7.2 Storage levels 16

7.3 Irrigation allocations 16

8. Appendix 18



2. Seasonal outlook Seasonal outlook and ENSO information are sourced from the Australian Bureau of Meteorology (BoM) and international sources. The BoM’s official outlooks are based on modelled output from the Predictive Ocean Atmosphere Model for Australia (POAMA), which is a dynamical (physics-based) climate model developed by the BoM and CSIRO Marine and Atmospheric Research. Further information on POAMA outlooks can be obtained here and at http://poama.bom.gov.au/.

Outlooks should be treated with caution when skill is low and strong climate drivers are lacking. In these situations, secondary influences (such as sea surface temperatures around the continent) may have a greater impact.

Changes in seasonal outlooks may have occurred since this report was released, and can be determined by clicking on the links provided. Seasonal outlook and ENSO information were collated in early April and were up to date as at 17 April 2015.

2.1 Seasonal outlook summary

Table 1: Seasonal outlook summary (BoM)

Current Outlook

Previous Outlook

Rainfall (quarter) Wetter Near neutral – neutral (central to north coast)

Near neutral - neutral Wetter (areas of far western NSW)

Max Temperature (quarter)

Warmer (eastern and east-central NSW) Near neutral (western, northern and central NSW)

Warmer Near neutral (north west, north east)

Min Temperature (quarter)

Warmer Warmer Near neutral (north east)

Outlook Legend: Grey = Neutral, i.e. equal chance of drier/wetter or warmer/cooler.

Red = Drier or warmer. Blue = Wetter or cooler. Source: Derived from information provided by the Australian Bureau of Meteorology.

2.2 Seasonal rainfall outlook • For the three month period from April to

June, wetter than normal conditions are likely across the most of NSW. The chances of exceeding median rainfall in these areas are more than 60%, increasing towards the west.

There is a near-equal chance of drier or wetter than normal conditions along the central to north coast, including the east of the Hunter and Northern Tablelands LLS districts (Figure 10).

• This means that for every ten years with similar climate patterns to those at present, across most of NSW about six to eight April to June periods would be expected to be wetter than normal, and three to four periods drier than normal.

• The past outlook accuracy (skill) is moderate to high across most of NSW, but low across the north west and northern/central areas of the Western LLS district (Figure 13).

• Of the global climate models surveyed, 20% suggested wetter than normal conditions for much of NSW over the period, 50% suggested neutral conditions (a near equal chance of wetter or drier than normal) and 30% drier than normal conditions.

2.3 Seasonal temperature outlook • Over the three month period from April to

June, warmer than normal daytime temperatures are likely across the coast, tablelands and areas of the slopes and the eastern edge of the plains. There is a near equal chance of warmer or cooler than normal daytime temperatures across most of western, central and northern NSW (Figure 11).

• The chances of exceeding median maximum temperatures range from 60-80% across the east of the State, with the highest probabilities in the far south east and the south coast to mid-north coast.

• This means that for every ten years with similar climate patterns to those at present, across eastern NSW about six to eight April to June periods would be expected to have warmer than normal daytime temperatures, and three to four periods cooler than normal.

• The past outlook accuracy (confidence or skill) for the maximum temperature outlook is moderate to high across most of NSW (Figure 13).

• Over the three month period from April to June, warmer than normal overnight temperatures are likely over NSW. The chances of exceeding median minimum temperatures exceed 80% (Figure 12).

• This means that for every ten years with similar climate patterns to those at present, across NSW eight or more April to June periods would be expected to have warmer

http://www.bom.gov.au/climate/poama2.4/about-POAMA-outlooks.shtml

http://poama.bom.gov.au/

http://www.bom.gov.au/climate/outlooks/#/overview/summary/


http://www.bom.gov.au/climate/outlooks/#/rainfall/median/seasonal/0

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than normal overnight temperatures, and two or less cooler than normal overnight temperatures.

• The past accuracy for the minimum temperature outlook is moderate to high across most of NSW, but low over the north east (Figure 13).

• Of the global climate models surveyed, 89% indicated that warmer than normal conditions are likely across NSW over the period and 11% cooler than normal conditions.

2.4 Monthly rainfall and temperature outlook

Monthly outlook information is sourced from the Australian Bureau of Meteorology (BoM). The multi-week and month 2 experimental climate outlooks from the POAMA model are provided with thanks to, and by special agreement with, the Bureau of Meteorology. However, they are experimental only, do not currently form part of the BoM’s standard services and are not yet fully calibrated. They should therefore be used with some caution. Feedback on the experimental outlooks can be provided to [email protected].

Monthly outlook summary

Table 2: Monthly outlook summary (BoM)

April May

Rainfall Near neutral – neutral (north east, northern central west, northern tablelands, mid-north to north coast) Wetter (west, south)

Drier (east/central and south) Near neutral-neutral (west/central)

Max Temperature Near neutral (south, south west) Warmer (northern, north east, central west, central tablelands, most of coastal NSW)

Warmer Near neutral – neutral (north east)

Min Temperature Warmer

Warmer Near neutral – neutral (north east)


Red = Drier or warmer. Blue = Wetter or cooler. Source: Derived from information provided by the Australian Bureau of Meteorology.

Month 1 - April • During April, wetter than normal conditions

are likely across western and southern NSW, and the southern areas of central NSW. There is a near-equal chance of drier or wetter than normal conditions across the north east, northern areas of central NSW, the northern tablelands and from the central to north coast. (Figure 14). In the former area, there is a 60-75% chance of wetter than normal conditions.

• The April rainfall outlook has a moderate past accuracy (skill) over most of the State, with areas of high accuracy in the north east. Past accuracy is low across areas of the far south east, areas of the north west and northern/central areas of the west.

• Recent unofficial updates to the April rainfall outlook suggest wetter than normal conditions are likely to extend across the whole State.

• Warmer daytime temperatures are likely across much of northern, north eastern and coastal NSW, the central west and central tablelands. Across the south and much of the west of the State, there is a near-equal chance of cooler or warmer than normal daytime temperatures (Figure 15).

• The April daytime temperature outlook has a moderate to high past accuracy (skill) across most of NSW.

• Recent unofficial updates to the maximum temperature outlook indicate a near-equal chance of warmer or cooler than normal daytime temperatures across the north and north west of the State, and cooler than normal conditions are likely in the east and south. Warmer than normal daytime temperatures are likely for the central coast.

• For most of NSW, warmer than normal overnight temperatures are likely during April (Figure 16).

• The April overnight temperature outlook has a low to very low past accuracy (skill) across western NSW, as well as areas of the far south and north east. Other areas of the State have a moderate past accuracy.

• Recent unofficial updates to the April minimum temperature outlook show warmer than normal conditions are likely.

April multi-week (as at 16 April) • Weekly experimental outlook information

suggests that during mid to late April (16-29 April) wetter than normal conditions are likely across most of NSW, but drier than normal in

http://poama.bom.gov.au/realtime/raintemp.shtml

http://poama.bom.gov.au/realtime/raintemp.shtml


mailto:[email protected]?subject=POAMA%20experimental%20outlook





the far north east. The past accuracy (skill) for this outlook is moderate to high.

• Daytime temperatures during mid to late April are likely to be warmer than normal across areas of northern NSW, but cooler than normal across most of the south. The far north east of the State has a near-equal chance of cooler or warmer than normal daytime temperatures. This outlook has a moderate to high accuracy (skill).

• Overnight temperatures during mid to late April are likely to be warmer than normal across the northern and central areas of NSW. Areas of the south and far south east of the State and cooler than normal in the south west. The past accuracy (skill) level for this outlook is moderate.

Month 2 - May • During May, wetter than normal conditions

are likely across western, central and southern NSW. The chances of exceeding median rainfall are 60-80% here, increasing towards the south west. There is a near-equal chance of drier or wetter than normal conditions in the north east (Figure 18).

• The May rainfall outlook has a moderate to high past accuracy across most of southern and central NSW, but a low past accuracy across the north, the northern tablelands, mid north to north coast, and much of the far west.

• There is a near-equal chance of cooler or warmer than normal daytime temperatures across most of NSW, with warmer than normal temperatures likely along the coast (Figure 18).

• The past accuracy (skill) for the May daytime temperature outlook is moderate across most of NSW, but low for areas of the Hunter valley, lower north coast, the south of the northern tablelands, and the far south east.

• Warmer than normal overnight temperatures are likely across NSW during May, with the probability of exceeding the median minimum temperature ranging from 65 to more than 80%, generally increasing towards the east (Figure 18).

• The past accuracy (skill) for the May overnight temperature outlook is low across most of NSW, but moderate in central NSW.

• Recent unofficial updates to the May outlooks indicate there is a near-equal chance of drier or wetter than normal conditions across NSW, although skill is low. Warmer than normal daytime temperatures

are likely in western, central and northern NSW. There is a near-equal chance of cooler or warmer than normal daytime temperatures in along areas of the coast and south. The overnight temperature outlook continues to show warmer than normal conditions are likely over most of northern NSW, but there is a near-equal chance of cooler or warmer than normal overnight temperatures in the south.

2.5 Other climatic models Seasonal outlook summary Information is provided for the UK Meteorology Office’s global long range probability modelled output and the APEC Climate Centre’s deterministic multi-model ensemble outlook.

Table 3: Seasonal outlook summary – UKMO and APCC

Apr-Jun UKMO APCC

Rainfall (quarter) Drier (eastern, northern, north western and areas of southern NSW) Neutral (western and areas of central NSW)

Near neutral

Overall Temperature (quarter)

Warmer

Warmer

UKMO Jun-Aug APCC Jul-Sep

Rainfall (quarter) Neutral Drier (north east and areas of central tablelands)

Near neutral (slightly wetter in far south west)

Overall Temperature (quarter)

Warmer (particularly coast, southern NSW)

Warmer (particularly coast, north west)


Red = Drier or warmer. Blue = Wetter or cooler. Source: Derived from information provided by the UK Met Office and the APEC Climate Centre.

2.6 El Niño-Southern Oscillation (ENSO) ENSO summary • ENSO is currently neutral, although sea

surface temperatures are warm across most of the equatorial Pacific. The Bureau of Meteorology’s ENSO tracker status has moved from ‘El Niño Watch’ to ‘El Niño Alert’.

http://www.metoffice.gov.uk/research/climate/seasonal-to-decadal/gpc-outlooks/glob-seas-prob


http://www.apcc21.org/eng/service/6mon/ps/japcc030703.jsp


http://www.apcc21.org/eng/service/6mon/ps/japcc030703.jsp



• The NOAA CPC/IRI indicated that (based on their thresholds and indicators) a weak El Niño event commenced in February and has about a 70% chance of continuing through winter.

• Note that model accuracy is low at this time of year, and does not improve until about May.

• Sea surface temperatures warmed in the eastern equatorial Pacific during March from below to above average, and are warm across most of the equatorial Pacific.

• Sub-surface warm temperature anomalies currently extend across the central and eastern equatorial Pacific.

• The SOI fell to be strongly negative in mid-late March but has since moved within the neutral range. Fluctuations in the SOI are common at this time of year. The 30-day SOI was -5.7 (as at 17 April). Fluctuations in the SOI are common at this time of year.

• Trade winds showed a continued and very strong reversal during March over the western equatorial Pacific, while remaining near normal in the east. A similar event occurred in February. Trade winds have also been consistently weaker than average this year, all of which has facilitated the warming of the Pacific Ocean sub-surface.

• Cloud at the junction of the equator and the International Date Line is consistent with an El Niño pattern. Cloud was reduced across northern Australia and most of the ‘Maritime Continent’ area to the north during the month.

• However, sea surface temperatures around the continent and in the Indian Ocean are a positive influence for potential rainfall, as shown by the seasonal rainfall outlook.

• Other indicators such as the thermocline slope index (near zero), the equatorial Pacific basin upper ocean heat anomalies (slightly positive), and the Oceanic Nino Index (+0.5°C) are considered by CPC/IRI to reflect weak El Niño conditions.

• All global climate models surveyed by the Bureau (as at 16 April) indicate sea surface temperatures in the NINO3.4 region during May are likely to be at or above the Bureau’s El Niño threshold. However, model accuracy is low at this time of year (the ‘autumn predictability gap’).

ENSO outlook and detailed comments

Table 4: ENSO/Climatic Outlook

Current Outlook (early April)

Previous Outlook (early March)

ENSO Status (overall)

Neutral – probable El Niño developing in winter (NOAA - weak El Niño)

Neutral – possible El Niño developing in winter (NOAA – weak El Niño)

BoM ENSO Tracker Status

El Niño Alert El Niño Watch

SOI Neutral (negative)

Neutral

Pacific Ocean SST (NINO3.4)

Warm (currently neutral, but near El Niño thresholds and warming)

Warm (currently neutral, but warming)

Indian Ocean (IOD) Neutral Neutral (currently negative)

Southern Annular Mode (SAM/AAO)

Near neutral – weakly positive

Near neutral – weakly negative

Summary Legend: Grey = Neutral, i.e. neither El Niño nor La Niña or no rainfall trend.

Red = El Niño/reduced rainfall trend. Blue = La Niña/higher rainfall trend. Source: Derived from information provided by the Australian Bureau of Meteorology and the US National Oceanic and Atmospheric Administration. • The Bureau of Meteorology’s ENSO tracker

(Figure 1) has moved from ‘El Niño Watch’ to ‘El Niño Alert’ on 14 April. This indicates that the Bureau considers that the probability of an El Niño event occurring (based on historical records) has increased from at least 50% to at least 70%.

• At ‘Alert’ level, the ENSO tracker and ENSO Wrap-Up may be updated weekly rather than fortnightly, and should be checked for more recent information.

Figure 1: Bureau of Meteorology ENSO tracker status

Source: Australian Bureau of Meteorology

• The Bureau of Meteorology’s POAMA model’s latest long range outlook (as at 12 April) indicates that the sea surface

http://www.bom.gov.au/climate/enso/

http://www.bom.gov.au/climate/enso/

http://www.cpc.ncep.noaa.gov/products/precip/CWlink/daily_ao_index/aao/aao_index_mrf.shtml


http://www.bom.gov.au/climate/enso/tracker/#tabs=Summary


http://www.bom.gov.au/climate/enso/#tabs=Overview






temperature anomalies in the NINO3.4 Pacific Ocean region are likely to increase to above the Bureau’s El Niño threshold during April-May and remain there during winter (Figure 2). Each of the individual ensembles (grey lines) are entirely above the El Niño threshold over winter and into spring.

• All of the eight global climate models surveyed by the Bureau of Meteorology (as at 16 April) indicate that sea surface temperatures in the NINO3.4 Pacific Ocean region are likely be at or above the Bureau’s the El Niño threshold in May. All of the models indicate sea surface temperatures in this region of above (and most well above) the threshold during July and September. However, model accuracy is low at this time of year and does not improve until May.

Figure 2: Current Bureau of Meteorology POAMA NINO3.4 Forecast

Source: Australian Bureau of Meteorology • The CPC/IRI ENSO Alert System Status

remains at ‘El Niño advisory’. This indicates El Niño conditions (meeting their thresholds and criteria) are observed and expected to continue.

• The CPC/IRI consensus ENSO forecast (as at 16 April) indicates that weak or borderline El Niño conditions developed during February and extended into March (based on their thresholds – see below), due to warming of sea surface temperatures in the NINO3.4 region and weak atmospheric coupling. The CPC/IRI consensus forecast indicates about a 70% likelihood that NINO3.4 temperatures at or above their threshold will continue through winter (Figure 3, Table 5).

• CPC/IRI expect a weak El Niño event through winter, but possibly increasing to moderate during spring. However, model forecast skill is low at this time of year (the ‘autumn predictability gap’).

Figure 3: CPC/IRI Consensus ENSO Forecast

Table 5: Current CPC/IRI consensus ENSO forecast probabilities (as at 5 March)

Season La Niña Neutral El Niño

Apr-Jun 0% 29% 71%

May-Jul 1% 29% 70%

Jun-Aug 2% 29% 69%

Jul-Sep 2% 30% 68%

Aug-Oct 3% 33% 64%

Sep-Nov 5% 34% 61%

Oct-Dec 6% 34% 60%

Nov-Jan 7% 34% 59%

Source: Climate Prediction Centre/International Research Institute for Climate and Society.

• Note that the CPC/IRI classifies values of the NINO3.4 index between -0.5°C and +0.5°C as indicating neutral conditions, rather than the -0.8°C to +0.8°C range used by the Bureau of Meteorology. This will result in differences when various meteorological organisations report that El Niño or La Niña conditions are developing.

• Adjusting the CPC/IRI plume-based data to the Bureau of Meteorology’s thresholds shows a reduced, but still 50% or greater probability of El Niño conditions during winter when all models are considered. When the dynamical models are considered alone, the probabilities are similar to those shown in Table 5 above.

Sea temperatures • Monthly sea surface temperature information

from the Bureau of Meteorology and the US National Oceanic and Atmospheric Administration (NOAA) showed rapid warming in the eastern equatorial Pacific during March and early April. Temperatures have continued to rise in the central equatorial Pacific and are close to the Bureau’s El Niño threshold. Sea surface

http://www.bom.gov.au/climate/poama2.4/poama.shtml


http://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/?enso_tab=enso-cpc_update

http://iri.columbia.edu/our-expertise/climate/forecasts/enso/current/

http://iri.columbia.edu/our-expertise/climate/forecasts/enso/

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temperatures are above average across almost the entire equatorial Pacific.

• The most recent monthly temperature anomaly value in the key NINO3.4 region is +0.58°C for March, up from +0.56°C during February.

• Weekly sea surface temperatures to 1 March were warm in the NINO 3.4 region (Figure 4) and close to the Bureau of Meteorology’s El Niño threshold. The temperature anomaly in the NINO 3.4 region at 12 April was +0.74°C.

• The sea surface temperature anomalies to 12 April were +0.68°C in the NINO 3 region, and +1.02°C in the NINO 4 region. The temperature anomaly in the NINO 1 region was +0.86°C, and the anomaly in the NINO 2 region was +1.63°C.

Figure 4: NINO3.4 Sea Surface Temperature Index


• The sub-surface sea temperatures show the development, gradual erosion and dissipation of a cool anomaly in the eastern Pacific between December and March. A positive anomaly developed in the western-central Pacific as a result of trade wind reversals and weakening in February and March, strengthened and moved eastwards (a downwelling Kelvin wave). This has contributed to the warming of the sea surface (Figure 5).

• Sub-surface temperatures across the western-central and eastern equatorial Pacific are now above average, with temperature anomalies at the centre of the Kelvin wave of 6°C above normal. A cool anomaly has developed at depth in the western equatorial Pacific.

Figure 5: Monthly sea sub-surface temperatures


Southern oscillation index (SOI) • The monthly value of the Southern

Oscillation Index is currently neutral at -5.7 as at 17 April (Figure 6, Table 6). The SOI fell to negative levels in mid-late March, but returned to neutral levels in mid-April. Fluctuations in the SOI are common at this time of year.

Table 6: Values of the Southern Oscillation Index

Current

monthly value (17 April)

Previous monthly value

(7 March)

SOI (30 day) -5.7 +0.3 Source: Australian Bureau of Meteorology.

Figure 6: 30 day moving SOI

Source: Australian Bureau of Meteorology • The Southern Oscillation Index is one factor

indicating the development and intensity of El Niño and La Niña events in the Pacific Ocean. It is calculated from variations in surface atmospheric pressure between

http://www.bom.gov.au/climate/enso/indices.shtml?bookmark=nino3.4

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Darwin and Tahiti. Values of the SOI between -8 and +8 indicate neutral conditions, sustained values above +8 may indicate a La Niña event, and sustained values below -8 may indicate an El Niño event.

Sub-tropical ridge (STR)/atmospheric pressure • The sub-tropical ridge was close to its

normal latitude for the time of year (over the 30 days to 7 April).

• There was slightly higher than normal atmospheric pressure over areas of western NSW during March, with near-normal pressure over the central and eastern areas of the State, and lower atmospheric pressure in the south east (Figure 7).

• During March, the sub-tropical ridge is normally around a pressure of 1018 hPa and is centred at around a latitude of around 38°S. However, in April the pressure increases to around 1021 hPa and the ridge normally moves north to around 35°S.

Figure 7: Monthly mean sea level pressure anomaly

Source: Australian Bureau of Meteorology. • The sub-tropical ridge is a zone of high

pressure which between January and March is normally located south of Australia at about 38°S to 39°S, and tends to suppress cold front activity. During June to September, it generally moves northwards to around 30°S to 32°S, allowing cold fronts to extend further into southern Australia.

Indian Ocean dipole (IOD) • The Indian Ocean dipole is currently neutral.

The latest IOD index value for the week ending 12 April is -0.13°C.

• The Bureau of Meteorology’s POAMA model and all climate models surveyed by the

Bureau of Meteorology currently favour a neutral IOD through to spring (Figure 8).

Figure 8: Current Bureau of Meteorology POAMA Indian Ocean Dipole Forecast

Source: Australian Bureau of Meteorology. • The IOD has little effect on Australian climate

until late autumn or winter. An IOD event usually starts between May and June, peaks in August to October and rapidly decays afterwards. It tends to have little influence from December to April, during the monsoon season.

• A negative IOD period (a sustained IOD index value of -0.4°C or less) is caused by warmer than normal water in the tropical eastern Indian Ocean and cooler than normal water in the tropical western Indian Ocean. A negative IOD period increases the chances of above normal rainfall during winter and spring across southern and much of western and central NSW, as shown in this link. A negative IOD can also contribute to below-average mean sea level pressure over Darwin, which may cause an increase in the SOI.

• A positive IOD period (a sustained IOD index value of +0.4°C or more) is the result of cooler than normal water in the tropical eastern Indian Ocean and warmer than normal water in the tropical western Indian Ocean. Positive IOD periods have been associated with a decrease in rainfall during winter and spring across southern, western and central NSW.

Trade winds and Pacific cloud conditions • Trade winds showed a continued and very

strong reversal during March over the western equatorial Pacific, while remaining near normal in the east. A similar event occurred in February. Trade winds have also been consistently weaker than average this year, all of which has facilitated the warming of the Pacific Ocean sub-surface.

• Easterly trade winds strengthen across the tropical Pacific during La Niña events and

http://www.bom.gov.au/cgi-bin/climate/cmb.cgi?page=map&variable=mslp&vstatus=anomaly&period=month&area=nat

http://www.bom.gov.au/cgi-bin/climate/cmb.cgi?page=map&variable=mslp&vstatus=anomaly&period=month&area=nat

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weaken or reverse during El Niño events. Weakening of the trade winds allows warmer than normal water to move into the central and eastern tropical Pacific Ocean.

• Cloud conditions at the equator near the International Date Line have been above average since early March. Over the last month, cloudiness has been below average in the west, with reduced convection across the Maritime Continent area.

• Cloudiness at the equator near and to the east of the International Date Line decreases during La Niña events and increases during El Niño events.

2.7 Other climatic indicators Southern annular mode (SAM) • The experimental Southern Annular Mode or

Antarctic Oscillation (AAO) index is currently weakly positive (as at 16 April).

• The outlook from POAMA (16 March) indicates the SAM index will remain moderately positive through to mid-April, then decline to weakly positive to neutral in late April and early May.

• The NOAA outlook is variable. The 10 day forecast suggests a similar outlook to POAMA through to mid-April, but the 14 day forecast suggests a weakly to moderately negative outlook.

• SAM outlooks tend to be extremely variable, particularly at lead times of two weeks or more, and the skill level for outlooks of 10-21 days tends to be low.

• A negative SAM event indicates an expansion of the belt of strong westerly winds towards the equator, resulting in more or stronger low pressure systems across southern Australia and potentially increased rainfall.

• A positive SAM event indicates the contraction of the belt of strong westerly winds towards Antarctica and higher pressures over southern Australia. During autumn and winter, a positive SAM event can potentially mean a decrease in rainfall across southern Australia. However, a strongly positive SAM in spring and summer can mean southern Australia is influenced by the northern half of high pressure systems, leading to a slightly higher likelihood of increased rainfall over south eastern and central NSW.

3. Rainfall 3.1 Relative rainfall Relative rainfall information is sourced from the AussieGRASS project of the Queensland Department of Science, Information Technology, Innovation and the Arts (QDSITIA) and from the Bureau of Meteorology.

Relative rainfall is calculated by comparing and ranking the rainfall for the current period against that for the same period over every year since 1889 (percentile ranks).

This means that if the current period has a rank of between 30 and 70 against all other years, it is regarded as being “average” and the conditions experienced will occur over about 4 out of every 10 years.

Summary

Table 7: AussieGRASS rainfall relative to historical records – percentage area of NSW in each class

Period Missing

data Below

Average (0-30%)

Average

(31-70%)

Above Average

(71-100%)

Month 5% 72% 22% 1%

Quarter 0% 16% 69% 15%

Half year 0% 26% 64% 10%

Year 0% 39% 51% 10%

Source: Derived from information supplied by the Queensland Department of Science, Information Technology, Innovation and the Arts.

March • Relative to historical records, rainfall for

March was below average (that is, rainfall in the 3rd decile or below) across 72% of the State.

• Below average rainfall extended across most of western, central, southern and south eastern NSW. This included most of the Western, Central West, Riverina, Murray and South East LLS districts. Below average rainfall also occurred across areas of all other LLS districts.

• Relative rainfall for March was extremely low (in the lowest 10% of years) over areas of western and southern NSW, and areas of the north west.

• Above average relative rainfall occurred over just 1% of the State, primarily in small pockets in the North West, Northern Tablelands and Hunter LLS districts.

http://www.bom.gov.au/climate/mjo/graphics/region.ts.dateline.small.gif

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http://www.longpaddock.qld.gov.au/about/researchprojects/aussiegrass/index.html

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• Average relative rainfall (that is, rainfall of between the 4th and 7th deciles) fell across 22% of NSW (Figure 19, Table 7), occurring primarily across the north east corner of the State and areas of the Central Tablelands, Northern Tablelands LLS districts and the east of the North West LLS district.

January to March (3 months) • Over the three month period from January to

March, relative rainfall was influenced by the above average January rainfall across most of NSW. Quarterly rainfall to March was average or above over 84% the State (Figure 20, Table 7).

• Above average relative rainfall occurred across 15% of the State. This included areas of the far west and isolated areas of the North Coast, Northern Tablelands, South East, Murray and Riverina LLS districts.

• Below average relative rainfall occurred over 16% of NSW and extended primarily across an area of north western NSW from Bourke to Walgett, Lightning Ridge, Goodooga, Narrabri, Carinda and Coonabarabran. Other areas of the North West LLS district around the Liverpool Plains also received below average rainfall, as did areas of the Northern Tablelands and Central West LLS districts.

• Over the remainder of NSW (69%), relative rainfall over the period was near average to average.

October to March (6 months) • Over the six months to March, relative

rainfall was average across 64% of NSW, above average across 10% and below average across 26% (Figure 21, Table 7).

• Above average relative rainfall for the period occurred primarily across areas of the South East LLS district, and in an area of Western LLS district between Broken Hill, Wilcannia and Tibooburra.

• A large area of below average relative rainfall for the period occurred across north western NSW and the northern central west. Other scattered areas of below average rainfall also occurred around Balranald, between Hay and Griffith, on the Liverpool Plains and in the central Northern Tablelands.

• Most of NSW (64%) had average to near average relative rainfall over the period.

April to March (12 months) • Over the twelve months to March, relative

rainfall was average across 51% of NSW,

above average across 10% and below average across 39% (Figure 22, Table 7).

• Areas of below average rainfall extended across the majority (90%) of North West and Central West (63%) LLS districts and the far north east and south east of Western LLS district. Below average rainfall occurred across the west of Murray and the west and south of Riverina LLS districts, particularly between Balranald, Hay and Griffith. Other areas occurred across Northern Tablelands LLS district between Armidale and Tenterfield, in the west and north of the Central Tablelands LLS district and in the central and western areas of the Hunter LLS district.

• Above average rainfall was restricted to areas of the far west of Western LLS district and the south of the South East LLS district.

3.2 Total rainfall Total rainfall information is sourced from the AussieGRASS project of the Queensland Department of Science, Information Technology, Innovation and the Arts and from the Bureau of Meteorology.

March • Overall, NSW received a State-wide rainfall

of 62% below normal during March. Rainfall was limited across much of central, southern and western NSW.

• Rainfall during March was generally associated with thunderstorm activity.

• Total rainfall ranged from 0-300 mm, with most of the rainfall concentrated in the east of the State. Much of western and central NSW received 0-10 mm. Areas of the north west between Brewarrina, Coonamble, Walgett and Lightning Ridge received little or no rainfall (Figure 23).

• Most of NSW received rainfall of less than 20% of normal for the month. Rainfall was greatest along the mid-north to north coast, the northern half of the northern tablelands and adjacent areas of the north west.

January to March (3 months) • Total rainfall over the three months to March

ranged from 25-1,200 mm over NSW, with most of the State receiving between 50-200 mm.

• The west generally received between 50-100 mm for the period, although areas of the north west, far west and south west received 25-50 mm. The central areas of the State received between 50-300 mm (Figure 24).






The tablelands and slopes generally received 100-300 mm. Most of the coastal strip, northern tablelands and Monaro received 100-300 mm, with areas of the central coast receiving 300-400mm. The north coast and areas of the mid-north coast received 300-600 mm, with limited areas receiving 600-1,200 mm.

October to March (6 months) • Rainfall across the State during the October

to March period ranged from 50-1,200 mm (Figure 25), with most of NSW receiving between 100-400 mm.

• The western areas of the State generally received 50-200 mm over the period, with 100-300 mm received across the central areas of NSW.

• The tablelands and upper slopes generally received 200-600 mm, with the northern tablelands generally receiving 400-600 mm. The coastal areas generally received 400-600 mm, with areas of the north and south coast receiving 600-800 mm, and areas of the north coast receiving 800-1,200 mm.

4. Temperature anomalies Temperature information is sourced from the Bureau of Meteorology.

The data used to create the temperature anomaly maps in Figure 27 and Figure 28 are slightly different from that used to create the anomaly maps on the Bureau of Meteorology website. The comments below reflect the website maps, which are more accurate, rather than those included in this report. The maps in Figure 27 and Figure 28 are provided for a general assessment only.

• Daytime temperatures were 1.4°C warmer than normal across NSW during March. Most of northern, north eastern and areas of central NSW were warmer than normal, particularly the north west (3-4°C above normal). Southern NSW was generally normal to cooler than normal.

• Overnight temperatures were 0.2°C above normal across NSW. Far northern NSW was warmer than normal, with other areas of the north and the central to north coast being near normal. Most of southern NSW was cooler than normal, particularly the far south and areas of the south west and far west.

5. Relative soil moisture Soil moisture information is sourced from the joint CSIRO and Bureau of Meteorology Australian Water Availability Project (AWAP).

The soil moisture maps presented in Figure 29 and Figure 30 show the average monthly soil moisture content for the topsoil and subsoil, as a proportion of its saturated capacity.

Monthly soil moisture levels relative to historical records (percentile ranks) are shown in Figure 31 and Figure 32. These percentile rank products use a relatively short comparative period of 1961-1990, which may result in large fluctuations in values from month to month.

5.1 Summary

Table 8: AWAP average monthly relative soil moisture (fraction) – percentage area of NSW in each class

Layer Low (0-0.3)

Moderate (0.3-0.7)

High (0.7-1.0)

Topsoil 89% 11% 0%

Subsoil 56% 37% 7%

Source: Derived from information supplied by CSIRO and the Australian Bureau of Meteorology.

5.2 Topsoil • Modelled topsoil moisture levels declined

across most of NSW except for areas of the north east and along the coastal strip north from Moruya (Figure 29). Levels across 89% of the State were in the lowest 30% of values, relative to a saturated profile.

• Most of western and central NSW had modelled topsoil moisture levels in the lowest 10% of values.

• Overall, 11% of NSW had moderate topsoil moisture (averaged over the month) (Figure 29, Table 8).

• On a percentile rank basis (Figure 31), topsoil moisture was generally below average across central, south western and southern NSW. Areas of extremely low relative topsoil moisture occurred across areas of the north west, central west and south west. Areas of the north east and far north west had average topsoil moisture.

• Total topsoil moisture levels were less than 10 mm across most of western and central NSW. Over the central and southern tablelands and coast, levels were generally between 10-40 mm. The northern tablelands, coast and south east had levels of generally

http://www.bom.gov.au/jsp/awap/temp/index.jsp



http://www.csiro.au/awap/


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20-40 mm. Over most of the mid-north to north coast, levels ranged from 40-150 mm.

5.3 Subsoil • Modelled subsoil moisture were generally

stable, but were low in areas of the north and west (Figure 30, Table 8). Some 56% of the State was in the lowest 30% of values, relative to a saturated profile.

• The lowest modelled subsoil moisture levels were in the north east, east and south of the Western LLS district, the west and south east of the North West LLS district, the north of the Central West, the west of Hunter and the west of Riverina and Murray LLS districts.

• Moderate levels of modelled subsoil moisture occurred across most of the tablelands and south west slopes. Moderate levels also occurred in the west of the Western LLS district, the south of Central West, the east and north of Riverina and the eastern areas of Murray LLS districts. Subsoil moisture levels were high across much of North Coast LLS district, as well as across all but the north west areas of the South East LLS district.

• On a percentile rank basis (Figure 32), subsoil moisture remained below average across much of the north west and areas of the northern tablelands, Liverpool Plains, central tablelands and areas of the Riverina.

• Areas of extremely low percentile rank subsoil moisture occurred primarily across areas of the North West LLS district and the far north east of Western LLS district.

• Areas of above average percentile ranked subsoil moisture occurred across areas of the far west, north coast and far south east and high across areas of the south east, far west and north coast.

• Total modelled subsoil moisture for the month was generally 50-200 mm across the western and central areas of the State, with levels of 200-300 mm in the far west. Areas of the north west and far south west had levels of less than 50 mm. Most of the coastal areas had modelled subsoil moisture levels of 200-400 mm.

6. Pasture growth and biomass Pasture growth and biomass information is primarily sourced from the AussieGRASS project of the Queensland Department of Science, Information Technology, Innovation and the Arts and used under licence.

The modelled total pasture growth and biomass levels should be used with some caution in the higher rainfall areas of NSW such as across the upper slopes, tablelands and coast. The pasture growth model is not as well calibrated for these areas as for the rangelands, plains and lower slopes.

Alternative pasture growth information is generated using the Growest model of the Fenner School of the Australian National University, with input data from the Australian Water Availability Project. Growth is generated for temperate grasses and legumes (C3 mesotherms) and tropical grasses (C4 megatherms). Growest is a simpler model than than GRASP, which is used to generate the AussieGRASS products. Initial assessments indicate it has some advantages over the AussieGRASS products for the upper slopes, tablelands and coast. However, there have been some calibration issues. Output is provided as an index from 0-1, rather than amounts of dry matter per hectare and is also converted to percentile ranks. Only monthly products are being generated at this stage. Maps of the products have not currently been included as the products are still undergoing development.

6.1 Pasture growth outlook Growth outlooks are based on modelled pasture and soil moisture conditions, modelled soil nitrogen levels and the phase of the Southern Oscillation Index (SOI) over the last one to two months.

The SOI phase is used to determine the likelihood of rainfall over the next three months, and is often different to the outlook from the Bureau of Meteorology POAMA model.

Growth outlooks are based on the probability of pasture growth over the next three months exceeding the long term (post 1957) median value.

The growth outlooks have varying levels of skill across NSW. As a result, they should be used with some caution. Skill levels are particularly low in autumn.

• The pasture growth outlook for April to June suggests above average growth over the period for the tablelands and upper slopes, with moderate to high skill levels, but average to slightly below growth for the Riverina, with low-moderate skill levels.

• Average to above average growth is likely in some areas of the far west.


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• For the rest of NSW, skill levels are low and outlook information has therefore not been included. This is normal at this time of year, due to fluctuations in the SOI.

6.2 Modelled pasture growth AussieGRASS modelled growth • Modelled pasture growth declined across

most of the State during March. Growth was low across western, central and north western NSW, as well as areas of the coast, central tablelands, northern tablelands and south west slopes.

• Across most of NSW, growth declined to less than 10 kg of dry matter (DM)/ha. Levels in the east of North West, areas of Central Tablelands and the north of the Northern Tablelands LLS districts varied from 20-200 kg DM/ha.

• In coastal areas, growth was variable with the highest levels in the north of North Coast LLS district (Figure 33).

• Note that the AussieGRASS modelled pasture growth output is best calibrated for the rangelands, plains and lower slopes. It is not as well calibrated for upper slopes, tablelands and coastal areas.

Growest modelled growth • The temperate pasture growth index for

March indicated moderate to high growth across the North Coast, the eastern edge and northern areas of the Northern Tablelands and the north east of Hunter LLS districts. Growth was generally low across the remainder of the State, particularly in the western and central areas.

• The tropical pasture growth index showed levels of moderate growth across most of North Coast LLS district and the far north east of Hunter LLS district.

• Relative to historical records, temperate pasture growth was well below average or worse across most of NSW. Relative growth was extremely low across the west of North West LLS district, the east of Western, the west of Murray and the western and southern areas of Riverina LLS districts. Growth was also extremely low in the south east of South East LLS district, and around Armidale in the Northern Tablelands LLS district.

• Average relative growth was limited to most of the North Coast, the north of Northern Tablelands, the east of North West and the north east of Hunter and Central Tablelands

LLS districts. There was also an area of average relative growth in the far north between Bourke and Wanaaring.

6.2 Modelled biomass • Modelled total standing dry matter (biomass)

levels were low across most of NSW during March, particularly across central NSW and areas of the west.

• Modelled biomass levels across the northern and central/eastern areas of the Western LLS district, Central West LLS district and all but the north east of the North West LLS district (Figure 34) were generally less than 500 kg of dry matter (DM)/ha, and in many areas were less than 250-500 kg DM/ha.

• Modelled biomass levels across the Riverina and Murray LLS districts also declined to generally less than 1,000 kg DM/ha, with most areas having less than 250 kg DM/ha.

• Levels of modelled biomass declined slightly across the Northern Tablelands, Central Tablelands, South East, Greater Sydney, Hunter and North Coast LLS districts. Biomass levels in these areas ranged from 250-1,000 kg DM/ha.

• Note that the AussieGRASS modelled biomass output is best calibrated for the rangelands, plains and lower slopes. It is not as well calibrated for upper slopes, tablelands and coastal areas.

6.4 Relative pasture growth AussieGRASS relative pasture growth and biomass are calculated by comparing and ranking the current modelled growth and biomass against that for the same period over every year since 1957 (percentile ranks).

This means that if the current period has a rank of between 30 to 70 against all other years, it is regarded as being “average” and the conditions experienced will occur over about 4 out of every 10 years.

Relative monthly pasture growth should be compared to modelled pasture growth for interpretation. ‘Average’ levels of relative growth may correlate with modelled levels (in kg/ha) that are quite low or high at certain times of year.



Summary

Table 9: AussieGRASS pasture growth and biomass relative to historical records – percentage area of NSW in each class

Period No

Data

Below Average (0-30%)

Average

(31-70%)

Above Average (71-100%)

Other

Growth

Month 21% 54% 18% 6% 1%

Quarter 1% 23% 48% 28% 1%

Half Year 1% 50% 39% 9% 1%

Year 0% 19% 55% 25% 1%

Biomass

Month 0% 35% 43% 21% 1%

Source: Derived from information supplied by the Queensland Department of Science, Information Technology, Innovation and the Arts.

March • Declines relative pasture growth between

February and March occurred across most of western, southern and south eastern NSW. Relative growth declined in most of these areas from average to well below average.

• Across the west, south and south east of North West LLS district, the north east of Western LLS district and across the majority of Central West LLS district, relative growth remained well below average to extremely low.

• Relative growth remained average or better across most of the Central Tablelands, North Coast, the north of the Hunter and the east of the North West LLS district.

• Relative pasture growth remained high across areas of the north of the Northern Tablelands.

• Relative to historical records, 54% of NSW had below average pasture growth during March (Table 9, Figure 35), although there were large areas of missing data across the west of the State.

• The area of the State with above average growth decreased to 6%. Average growth occurred across 18% of NSW.

January to March (3 months) • Over the quarter to March, relative pasture

growth was still influenced by the January rainfall. However, areas of below average relative growth expanded in the north west, the south west and the far south east.

• Over the quarterly period, relative growth was average or better across 76% of the

State. Relative growth was below average over 23% of the State, an increase from 11% in the period to March (Table 9, Figure 36).

• Relative growth remained high in the far west of Western LLS district, across most of the tablelands, south west slopes and the central/southern areas of Murray LLS district. Relative growth across the coast and much of Western LLS district was average.

• Below average relative growth occurred in the north east, east and south east of Western LLS district, the western, central and Liverpool Plains areas of North West, the west of Riverina and some areas of the Monaro in South East LLS district.

October to March (6 months) • Over the six month period from October to

March, relative pasture growth continued to decline across most of north western, central and southern NSW. Relative growth was below average across most of North West, Central West and Riverina LLS districts, as well as the much of the west of Murray and the east and north of Western LLS districts. Relative growth was also low in the south of the Northern Tablelands and the west of the Greater Sydney LLS districts.

• Relative growth remained average across most of the coast and tablelands. An area of above average growth also occurred in Western LLS district between Broken Hill, Wilcannia and Tibooburra.

• Relative growth over the period was average or above over 48% of the State (Table 9, Figure 37), and above average over just 9% of the State. Below average relative growth occurred across 50% of the State.

April to March (12 months) • Yearly relative growth was average or above

across 80% of the State (Table 9, Figure 38), with 55% of the State having average relative growth.

• Below average relative growth for the period covered 19% of the area of the State and extended across 63% of the North West LLS district. Between Walgett, Lightning Ridge and Goodooga, and around Moree, relative growth was extremely low (relative growth in the lowest 10% of years).

• Areas of below average relative growth also occurred across the north east of Western LLS district between Wanaaring and Brewarrina, the south east of North West LLS district around the Liverpool Plains and the west of Riverina LLS district around Hay.





• Areas of above average growth occurred in the far west of the Western LLS district, across the tablelands, areas of the upper slopes and coast and in the west of Central West LLS district.

6.5 Relative biomass Relative monthly biomass should be compared to modelled biomass for interpretation. “Average” levels of relative biomass may correlate with modelled levels (in kg/ha) that are quite low or high at certain times of year.

• Relative biomass levels declined between February and March. The area of well below average and extremely low relative biomass increased in the North West and the north east of Western LLS districts, as well as across the Central West and the Riverina LLS districts (Table 9, Figure 39).

• Levels of average relative biomass remained stable. Relative to historical records, biomass was average to above average across most of the coast, tablelands and south west slopes, and the far west.

7. Streamflow, water storage and irrigation allocations Streamflow information is sourced from experimental products of the AussieGRASS project and from the Bureau of Meteorology. Irrigation allocations and storage levels are sourced from the NSW Office of Water. Comments on farm water supplies are sourced from Local Land Services.

7.1 Streamflow • Streamflow analysis indicated areas of below

average run off have increased substantially over one, two and three year time periods. In the last year, streamflow over much of northern and central NSW, the tablelands, Hunter valley, Sydney basin and the Riverina has been well below average.

• Farm water supplies are low in many areas, with some areas critically low in March. Storm rainfall and rainfall in early-mid April has resulted in some run off, particularly in areas of central and eastern NSW.

• The Bureau of Meteorology's streamflow forecast indicates low streamflow was recorded in March at most locations and is likely at most locations during April to June.

7.2 Storage levels Storage levels are shown as at 8 April 2015 and are compared to those at 4 March in Figure 9.

• Levels in water storages were generally low-moderate, with the average capacity being 41%. There were increases at Pindari and Wetherell during the month. The greatest decreases were at Lake Cargelligo (-24%), Hume Dam (-16%), Oberon Dam (-8%) and Lake Pamamaroo (-6%) (Figure 9).

7.3 Irrigation allocations Allocations are given as at 8 April 2015.

• General security allocations remained unchanged from March, except for an increase in the allocation for the Murray from 59-61% (Table 10).

Table 10: Irrigation allocations

River valley Allocation Licence category

NSW Border Rivers* 67.1% General security A

Class

0% General security B Class

100% High security Richmond 100% General security 100% High security Gwydir* 0% General security 100% High security Hunter 100% General security 100% High security Paterson 100% General security 100% High security Lachlan* 0% General security 100% High security Belubula* 0% General security 100% High security Lower Darling* 100% General security 100% High security Macquarie and Cudgegong* 2% General security

100% High security Murray* 61% General security 97% High security Murrumbidgee* 51% General security 95% High security Lower Namoi* 0% General security 100% High security Upper Namoi* 100% General security 100% High security Peel 0% General security 50% High security Bega Brogo 70% General security 100% High security *Carry over water may be available


http://www.bom.gov.au/water/ssf/

http://www.water.nsw.gov.au/

http://www.lls.nsw.gov.au/



http://realtimedata.water.nsw.gov.au/water.stm?ppbm=STORAGE_SITE&da&3&dakm_url

http://www.water.nsw.gov.au/Water-management/Water-availability/Water-allocations/water-allocations-summary/default.aspx



Figure 9: Capacity of storages



8. Appendix Maps and data used in the production of this report.

Seasonal rainfall and temperature outlook

Figure 10: Quarterly rainfall outlook

Figure 11: Quarterly maximum temperature outlook



Figure 12: Quarterly minimum temperature outlook

Figure 13: Outlook skill maps



Month 1 rainfall & temperature outlook

Figure 14: Month 1 rainfall outlook

Figure 15: Month 1 maximum temperature outlook



Figure 16: Month 1 minimum temperature outlook

Figure 17: Month 1 outlook skill maps



Month 2 rainfall & temperature outlook (Bureau of Meteorology, POAMA) Note – Operational Bureau of Meteorology month 2 outlook maps will be available in the near future.

Figure 18: Month 2 rainfall and temperature outlooks

http://www.bom.gov.au/climate/outlooks/#/overview/summary



Rainfall

Figure 19: Relative rainfall – monthly

Figure 20: Relative rainfall – quarterly



Figure 21: Relative rainfall – half yearly

Figure 22: Relative rainfall – yearly



Figure 23: Total rainfall – monthly

Figure 24: Total rainfall – quarterly



Figure 25: Total rainfall – half yearly

Figure 26: Total rainfall – yearly



Temperature Note - The data used to create the temperature anomaly maps in Figure 27 and Figure 28 are slightly different from that used to create the anomaly maps on the Bureau of Meteorology website. The website maps are more accurate and should be used in preference.

Figure 27: Maximum monthly temperature anomaly

Figure 28: Minimum monthly temperature anomaly




Soil moisture

Figure 29: Relative monthly topsoil moisture (fraction of a saturated profile)

Figure 30: Relative monthly subsoil moisture (fraction of a saturated profile)



Figure 31: Relative monthly topsoil moisture (percent rank)

Figure 32: Relative monthly subsoil moisture (percent rank)



Pasture growth and biomass

Figure 33: Modelled pasture growth

Figure 34: Modelled biomass



Figure 35: Relative pasture growth – monthly

Figure 36: Relative pasture growth – quarterly



Figure 37: Relative pasture growth – half yearly

Figure 38: Relative pasture growth – yearly



Figure 39: Relative biomass – monthly



More information

For more information, contact the NSW Department of Primary Industries on 02 6391 3100 or Local Land Services on 1300 795 299.

The Seasonal Conditions Summary, a shortened version of this document, is available at http://www.dpi.nsw.gov.au/agriculture/emergency/seasonal-conditions/regional-seasonal-conditions-reports. A link to join the Seasonal Conditions mailing list is also available at that site.

A four-page simplified summary of the seasonal outlook and the current conditions is provided in the NSW Climate Summary, available at www.dpi.nsw.gov.au/agriculture/emergency/seasonal-conditions/summary.

Acknowledgments Information used in this report was sourced from the Australian Bureau of Meteorology, CSIRO, Queensland Department of Science, Information Technology, Innovation and the Arts, NSW Local Land Services, the US National Oceanic and Atmospheric Administration, the International Research Institute for Climate and Society (Columbia University), the UK Meteorological Office, the APEC Climate Centre and NSW Department of Primary Industries.

Warning Recognising that some of the information in this document is provided by third parties, the State of New South Wales, the author and the publisher take no responsibility for the accuracy, currency, reliability and correctness of any information included in the document provided by third parties.

© State of New South Wales through the Department of Trade and Investment, Regional Infrastructure and Services, 2015. You may copy, distribute and otherwise freely deal with this publication for any purpose, provided that you attribute the NSW Department of Primary Industries as the owner.

Disclaimer: The information contained in this publication is based on knowledge and understanding at the time of writing (April 2015). However, because of advances in knowledge, users are reminded of the need to ensure that information upon which they rely is up to date and to check currency of the information with the appropriate officer of the Department of Primary Industries or the user’s independent adviser.

Published by the Department of Primary Industries.

ISSN 2202-1795 (Online)

PUB15/138

Volume 3/Number 3

Jobtrack 12948

http://www.dpi.nsw.gov.au/agriculture/emergency/seasonal-conditions/regional-seasonal-conditions-reports

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