How Much Accumulation of Snow Are We Supposed to Get

Probabilistic Snowfall Forecasts
WY Probabilistic Snowfall Forecasts
Ice Accumulation Forecasts
WY Ice Accumulation Forecasts
Onset/End-Timing Graphics
Winter Storm Outlook and Winter Storm Severity Index
Snow and Ice Observations
Medium/Long Range Forecast

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Snow Amount Potential
Expected Snowfall - Official NWS Forecast Point Range What's this?	High End Amount 1 in 10 Chance (10%) of Higher Snowfall What's this?
	Low End Amount 9 in 10 Chance (90%) of Higher Snowfall What's this?
Low End Amount – 9 in 10 Chance (90%) of Higher Snowfall This map depicts a reasonable lower-end snowfall amount for the time period shown on the graphic, based on many computer model simulations of possible snowfall totals. This lower amount is an unlikely scenario with a 9 in 10, or 90% chance that more snow will fall, and only a 1 in 10, or 10% chance that less snow will fall. This number can help serve as a lower-end scenario for planning purposes. Expected Snowfall - Official NWS Forecast This map is the official NWS snowfall forecast in inches during the time period shown on the graphic. This snowfall amount is determined by NWS forecasters to be the most likely outcome based on evaluation of data from computer models, satellite, radar, and other observations. High End Amount – Only a 1 in 10 Chance (10%) of Higher Snowfall This map depicts a reasonable upper-end snowfall amount for the time period shown on the graphic, based on many computer model simulations of possible snowfall totals. This higher amount is an unlikely scenario, with only a 1 in 10, or 10% chance that more snow will fall, and a 9 in 10, or 90% chance that less snow will fall. This number can help serve as an upper-end scenario for planning purposes.

Percent Chance That Snow Amounts Will Be Greater Than...

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Percent Chance That Snow Amounts Will Be Greater Than

This series of maps shows the probability (that is, the likelihood) that snowfall will equal or exceed specific amounts during the time period shown on the graphic. These forecasts are based on many computer model simulations of possible snowfall totals.

Hover over thumbnails below to view larger image.

>=0.1"	>=1"	>=2"	>=4"	>=6"	>=8"	>=12"	>=18"

Snowfall Totals by Location What's this?

Snowfall Totals by Location

These tables show the snowfall forecast for individual locations, and provide the same information as the graphics on this web page, just shown in a different way. All of these values are valid for the same time period as depicted on the graphics.

Snow Amount Potential
Expected Snowfall - Official NWS Forecast Point Range What's this?	High End Amount 1 in 10 Chance (10%) of Higher Snowfall What's this?
	Low End Amount 9 in 10 Chance (90%) of Higher Snowfall What's this?
Low End Amount – 9 in 10 Chance (90%) of Higher Snowfall This map depicts a reasonable lower-end snowfall amount for the time period shown on the graphic, based on many computer model simulations of possible snowfall totals. This lower amount is an unlikely scenario with a 9 in 10, or 90% chance that more snow will fall, and only a 1 in 10, or 10% chance that less snow will fall. This number can help serve as a lower-end scenario for planning purposes. Expected Snowfall - Official NWS Forecast This map is the official NWS snowfall forecast in inches during the time period shown on the graphic. This snowfall amount is determined by NWS forecasters to be the most likely outcome based on evaluation of data from computer models, satellite, radar, and other observations. High End Amount – Only a 1 in 10 Chance (10%) of Higher Snowfall This map depicts a reasonable upper-end snowfall amount for the time period shown on the graphic, based on many computer model simulations of possible snowfall totals. This higher amount is an unlikely scenario, with only a 1 in 10, or 10% chance that more snow will fall, and a 9 in 10, or 90% chance that less snow will fall. This number can help serve as an upper-end scenario for planning purposes.

Percent Chance That Snow Amounts Will Be Greater Than...

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What's this?

Percent Chance That Snow Amounts Will Be Greater Than

Hover over thumbnails below to view larger image.

>=0.1"	>=1"	>=2"	>=4"	>=6"	>=8"	>=12"	>=18"


Ice Accumulation Potential
What's this?
Most Likely Ice Accumulation Represents our official ice forecast in inches within the next one to three days. The ice accumulation amounts are provided in ranges.


Ice Accumulation Potential
What's this?
Most Likely Ice Accumulation Represents our official ice forecast in inches within the next one to three days. The ice accumulation amounts are provided in ranges.

Onset of Wintry Precipitation	End Timing of Wintry Precipitation
Precipitation Onset/End Timimg

What's this?	What's this?
Precipitation Onset Most likely time of winter precipitation onset (snow, sleet, freezing rain). Rain is not included here. This information is provided when we issue a Warning or Advisory for expected snow or ice accumulation; typically six to 24 hours in advance. Times are only given for places that are under a Warning or Advisory. They will be blank in areas outside Warnings or Advisories. Precipitation End Time Most likely time of winter precipitation ending (snow, sleet, freezing rain). Rain is not included here. This information is provided when we issue a Warning or Advisory for expected snow or ice accumulation; typically six to 24 hours in advance. Times are only given for places that are under a Warning or Advisory. They will be blank in areas outside Warnings or Advisories.

Winter Storm Severity Index (WSSI)	Winter Storm Outlook (WSO)

National Snow Reports	National Snowfall Analysis


Local Snow Reports

Days 4-7 Winter Weather Outlook

Day 4 Winter Weather Outlook	Day 5 Winter Weather Outlook


Day 6 Winter Weather Outlook	Day 7 Winter Weather Outlook

Click here for an interactive map

CPC Week-2 Experimental Heavy Snow Risk



CPC Temperature & Precipitation Maps

Days 6-10
Temperature	Precipitation



Days 8-14
TEMPERATURE	PRECIPITATION



Week 3-4
TEMPERATURE	PRECIPITATION