Baltimore/Washington

Weather Forecast Office

Winter (DEMO)

The purpose of these experimental probabilistic snowfall products is to provide customers and partners a range of snowfall possibilities, in complement to existing NWS deterministic snowfall graphics, to better communicate forecast uncertainties during winter weather events. For more information visit this project's Product/Service Description Document, and please provide us your feedback here.

THIS PAGE FOR DEMONSTRATION PURPOSES ONLY.

EXPECT AT LEAST THIS MUCH	MOST LIKELY SNOWFALL	POTENTIAL FOR THIS MUCH
Snow Accumulation Potential Experimental - Leave feedback
	Point / Range

What's this?	What's this?	What's this?
Minimum Potential Accumulation Expect at least this much. This is what we see as the least amount of snow the storm can produce. This information is for advance planning ahead of the storm. It is provided out as far as three days. However, when the snow starts to fall, this will be discontinued to focus on the forecast snow amount. Most Likely Snow Accumulation Represents our official snow forecast in inches within the next one to three days. The snowfall amounts are provided in point (single number) and ranges (1-2", 2-4", etc.). You can toggle between the two by hovering over the "Point" and "Range" text above the image. The point amount is our forecast but the range for the "most likely" represents the forecast uncertainty in predefined ranges. Maximum Potential Accumulation What you should be prepared for. This is what we see as the storm's maximum potential snowfall accumulation. This information is for advance planning ahead of the storm. It is provided out as far as three days. However, when the snow starts to fall, this will be discontinued to focus on the forecast snow amount.

Ice Accumulation Potential

MOST LIKELY ICE GLAZE

What's this?

Impacts

Amount Forecast

Icy Spots Expected
Beware driving or walking. Some areas will be icy, some not.

Up to a Tenth

Widespread Icing
Limit unnecessary travel. Any untreated surface will likely be glazed with ice. Scattered power outages possible.

Tenth to a Quarter Inch

Ice Storm Expected
Numerous power outages. Downed branches. Extremely dangerous to walk or drive on untreated surfaces that will be ice covered.

Quarter Inch to a Half Inch

Severe Ice Storm
Widespread power outages, possibly for an extended time. Downed trees, and impassable roads expected.

Half Inch to an Three-Quarter Inch

Severe Ice Storm
Widespread power outages, possibly for an extended time. Many downed trees, and impassable roads expected.

Three-Quarter Inch up to an Inch

Devastating Ice Storm
Long term power outages. Many downed trees over roads and power lines. Impassable roads from icing and downed trees. Recovery could take many days.

Inch up to 2 Inches

Devastating Ice Storm
Long term power outages. Many downed trees over roads and power lines. Impassable roads from icing and downed trees. Recovery could take many days.

2 Inches or More

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

Experimental - Leave feedback

What's this?

Hover over thumbnails below to view larger image.

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

Chance of Snow Accumulation

Experimental - Leave feedback

What's this?

Storm Track	Onset of Wintry Precipitation	Reported Snow/Ice Totals
Other Snow/Ice Information

What's this?	What's this?	What's this?
Low Tracks Graphic The graphic depicts the forecast location of significant surface lows impacting the 48 contiguous United States in 12 hour increments out to 72 hours into the future. The low position and track forecast by NCEP WPC meteorologist is in white. Each low position is accompanied by a lead time (Eastern Time). The circles around each low represents a 75% probability the observed low will be located with the circle. Note: The probability is derived using previous season's verification data. For reference, existing surface lows are depicted with a red marker without yellow circles. 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. Reported As snow and/or ice reports come into the NWS (you can email reports to lwx-report@noaa.gov or Tweet to @NWS_BaltWash), we will pass them on here. With the map linked here, and the supporting reports below it, you can keep tabs on how much has fallen.

Winter Storm Threat: 3-7 Days From Now...

Experimental - Leave feedback

What's this?

Click on maps to see daily Confidence vs. Potential Impact graphic.

Hover over thumbnails below to view larger image.

Day 3	Day 4	Day 5	Day 6	Day 7

Long-Range Forecast

Days 4-5 Forecast Precipitation	Days 6-7 Forecast Precipitation


Days 6-10
Temperature	Precipitation


Days 8-14
TEMPERATURE	PRECIPITATION


Week 3-4
TEMPERATURE	PRECIPITATION

Useful Winter Weather Information
Historic Mid-Atlantic Winter Storms	Winter/Snowfall Statistics	El Niño and DC/Baltimore Winters
Watches, Warnings, & Advisories	How to Measure Snow	La Niña and DC/Baltimore Winters
BE PREPARED!
At Home	On the Road	Outside in the Cold