Snow, Sleet, Freezing Rain. To make snow, the temperature must be below freezing the entire path...

Post on 31-Mar-2015

220 views 5 download

Tags:

Transcript of Snow, Sleet, Freezing Rain. To make snow, the temperature must be below freezing the entire path...

Snow, Sleet, Freezing

Rain

To make snow, the temperature must be below freezing the entire path until at the surface.

Once snow melts as it is falling, it will not turn back into snow again, no matter the temperature.

Melted snow that drops below freezing will stay liquid, called "supercooled". This is freezing rain.

If freezing rain completely refreezes, it will become sleet.

SNOW

T < 32 °F

SNOW

T < 32 °F

T < 32 °F

T > 32 °F RAIN

SLEET

SNOW

T < 32 °F

T < 32 °F

T > 32 °F RAIN

FREEZING RAIN

5 °C (40 °F)

at 6000 ft-5 °C (23

°F)at 1000 ft

7 °C (44 °F)

at 3000 ft-4 °C (25

°F)at 1500 ft

SNOW

T < 32 °F

T > 32 °FRAIN

SNOW

T < 32 °F

Tuesday January 20th (7 days in advance) Outlook: Large winter system will affect area on

Monday and Tuesday. Forecast Tuesday: 50% chance of snow.

Wednesday January 21st

Outlook: Significant weather system will impact area early next week...accumulations of snow, sleet, and freezing rain late Monday Night and Tuesday.

Forecast Tuesday: 60% chance of light snow. Light snow accumulations.

Thursday January 22nd

Outlook: Storm system will impact area late Monday and Tuesday...wintery mix

Forecast Tuesday: 60% chance of light snow. Light snow accumulations.

Friday January 23rd Outlook: Storm system will likely spread wintery precipitation

Late Monday through Early Wednesday...significant accumulations possible.

Forecast Monday Night & Tuesday: 60% chance of snow. significant snow accumulations possible.

Saturday January 24th

Outlook: Big winter storm will impact area Late Monday through Wednesday...significant snow and ice accumulation are expected Late Monday Night through Tuesday Night.

Forecast Tuesday: 70% chance of snow and slight chance of sleet. Light snow accumulations.

Sunday January 25th

Preliminary Conference Call Winter Storm Watch: Two waves...first wave, 3 to 6 inches of

snow...second wave, quarter inch of ice. Forecast

Monday Night: 3 to 6 inches of snow. Tuesday & Tuesday Night: Freezing rain, sleet & snow.

Monday January 26th Conference Calls Winter Storm Warning: Snow, sleet, and ice...3 to 4

inches of snow by Tuesday Morning with an additional 1 to 2 inches of snow and sleet Tuesday Night.

Forecast Monday Night: 3 to 5 inches of snow. Tuesday: Sleet and snow until midday then sleet,

freezing rain and snow in the afternoon. Snow and sleet accumulation of 1 to 2 inches...tenth of an inch ice.

Tuesday Night: Freezing rain and sleet in the evening, snow after midnight. Snow and sleet accumulation of 1 to 2 inches...quarter of an inch of ice.