National Weather Service Middle Atlantic River Forecast Center River Flood Potential Briefing
FORECAST OPERATIONS STUDY · FLOOD MANAGEMENT PARADIGM SHIFT • New – Harness forecasting...
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FOLSOM JOINT FEDERAL PROJECT FORECAST OPERATIONS STUDY Photo courtesy of USACE-SPK Brett Whitin – California Nevada River Forecast Center Randi Field – U.S. Bureau of Reclamation
Transcript of FORECAST OPERATIONS STUDY · FLOOD MANAGEMENT PARADIGM SHIFT • New – Harness forecasting...
FOLSOM JOINT FEDERAL PROJECTFORECAST OPERATIONS STUDY
Photo courtesy of USACE-SPK
Brett Whitin – California Nevada River Forecast CenterRandi Field – U.S. Bureau of Reclamation
FOLSOM LAKE
Storage Capacity: 976,000 acre feet(1.204x109 m3)
Watershed: 1,861 square miles (4,820 km2)
Multi-Objective Reservoir
High Refill Potential
Upstream of Urban Area - Sacramento
AMERICAN RIVER HYDROLOGIC MODEL
AMERICAN RIVER HYDROLOGIC MODEL
Hindcast:- Ensemble forecast performed for historical time period
using current forecasting methodology (1985-2010)- Meteorological Ensemble Forecast Preprocessor (MEFP)
using GEFSv10 precip and temp- Run the forcings through our hydrologic models
Value of Hindcasts:Provide a large and consistent sample for verification
Bottom Line: demonstrate forecast quality/reliability
Hindcasting
He
ENSEMBLE RIVER FORECASTS
Timeline
Mod
el R
un T
ime
Observed Weather
Streamflow
Model States
Short Term Weather Models(GEFS)
Days 1-15
Hourly ensemble inflow forecasts to Folsom
- 61 traces per day• Daily forecasts for 1985-2010
HINDCAST FINAL PRODUCTS
HINDCAST VERIFICATION OF RESULTS
FOLSOM 3-DAY AVERAGE FLOW
(MEAN ENSEMBLE FORECAST VS. OBSERVED)
FOLSOM 3-DAY 25% EXCEEDENCE FLOW
(MEAN ENSEMBLE FORECAST VS. OBSERVED)
FOLSOM 1986 3-DAY INFLOW VOLUME
Feb
12th
Feb
13th
Feb
14th
Feb
15th
Feb
16th
Feb
17th
FOLSOM FEB18-20 (3-DAY) VOLUME FORECAST PROGRESSION
FLOOD MANAGEMENT PARADIGM SHIFT
• Old – Upstream Storage Credit– Conservative from a flood protection perspective– Precipitation measurements already “on the ground” – Leverage existing flood reserve space
FLOOD MANAGEMENT PARADIGM SHIFT• New
– Harness forecasting technology– Increase flood preparation “Advanced-release” – Increase water supply use efficiency
MANAGEMENT GOALS
1. Use advanced release to improve flood risk2. Reduce Safety of Dams and high release risks3. Increase water supply use efficiency
FORECAST INFORMED DESIGN STRUCTURE
1. Advance Release “Blue Sky Action”2. Evacuate storage prior to a storm event3. Communication Opportunities4. Forecast Dynamics
FORECAST INFORMED DECISION MAKING PROCESS
Ensemble
Model Runs
FORECAST INFORMED DECISION MAKING PROCESS
392
417
442
467
492
517
542
567
592
617
642325
350
375
400
425
450
475
500
525
550
575
0 10020030040050060070080090010001100120013001400150016001700 Floo
d Co
ntro
l Res
erva
tion
(FCR
) (10
00 a
c-ft
)
Top
of C
onse
rvat
ion
(TO
C) S
tora
ge (1
000
ac-
ft)
Forecasted Inflow Volume (1,000 ac-ft)
Variable Top of Conservation
24-hr
48-hr
72-hr
120-hr
TOC
25% Exceedance Probability
Cumulative Volume for Day 1, 2, 3, and 5
Test if Cumulative Volume > 300,000 acre feet
Yes
No
Increase Release based on Confidence and Risk
Maintain current Release
FORECAST INFORMED DECISION MAKING
NEW WATER CONTROL MANUAL SIGNED(JUNE 12TH 2019)
