First call for snow accumulation Friday afternoon and evening

Update, 1:30 p.m.: The European model has come in with a simulation for very light amounts of snow Friday afternoon (probably around 1”).

From 11:47 a.m.: A weak - emphasis on weak - storm system will pass to our south Friday, probably producing a short period of light snow. Although we’re underwhelmed by the storm’s available moisture, its timing raises concerns for the Friday afternoon and evening commute.

Areas of light snow could develop between 2 and 5 p.m. before tapering off between 7 and 11 p.m. Like today’s event, temperatures will be in the 20s, allowing any flakes that fall to stick.

While the commute could be disrupted with slick roads and reduced visibilities, this will not be crippling snowfall and it’s not out of the question it amounts to very little.

Upper level energy forecast to move through the region late Friday should help generate enough lift for some light snow (

As we discussed yesterday, storms that come from the west often get stripped of their moisture when they cross the mountains (producing a snow hole). This morning’s GFS model sucks all the moisture out of the storm, giving us almost no snow. But most other models give us at least a little something, and we’re leaning in that direction. Even though the storm lacks moisture, it should be energetic enough to generate lift and produce some precipitation.

Wes Junker, CWG’s winter weather expert, passed along these thoughts:

This is another moisture-starved system making this another tough forecast. Two scenarios remain and each is equally likely.

The choices now are 1) a quick 1-2 inches starting late in the afternoon or early evening and continuing through rush hour making the commute dicey if the wetter model scenarios play out, or 2) a quick dusting to inch if the drier ones prevail.

In this latter scenario, the westerly flow and the resultant down-sloping east of the mountains help dry out the system allowing forming a dry slot or snow hole. This would lead to only very light precipitation amounts. Either scenario is equally likely so the best and safest forecast is probably to call for a dusting to 2 inches.

In many respects, snow totals may closely resemble those from today’s event, although we don’t expect a snow maximum in southern Maryland this time. Areas along and west of the Blue Ridge probably see the most snow from this storm system.

Within the Washington, D.C. region, it’s difficult to pinpoint who will see the most or least snow. It’s not out of the question someone sees more than 2 inches if some heavier bands develop - which is a possibility. And it’s equally likely someone in the region sees little more than some conversational flakes.

We’ll refine this forecast in future updates.