Yesterday morning at dawn. (Kevin Wolf via Flickr)

* Winter storm watch Monday evening into Tuesday afternoon *

TODAY’S DAILY DIGIT
A somewhat subjective rating of the day’s weather, on a scale of 0 to 10.

3/10: The only good thing about all this cold is that it sets the stage for possible accumulating snow!

EXPRESS FORECAST

Today: Partly to mostly sunny and cold. Highs: Low-to-mid 40s.
Tonight: Mostly clear and chilly. Lows: Near 20 to mid-20s.
Tomorrow: Increasing clouds, snow likely by evening. Highs: Low-to-mid 40s.

View the current weather conditions at The Washington Post headquarters.

FORECAST IN DETAIL

We’ll get to the snow soon enough. First, though, we get another bright but cold day to close out the weekend. Our late-season snow threat (a Hail Mary for snow lovers) looks to arrive tomorrow evening with heavy snow possible during the night before tapering early Tuesday. But models still disagree on who sees how much snow and whether rain or sleet mix in for some.

A March snowstorm is rare, but not unprecedented in the D.C. region. (Claritza Jimenez/The Washington Post)

Today (Sunday): We’re still on the cold side, with morning temperatures rising through the 20s, only reaching the low-to-mid 40s for afternoon highs. Partly to mostly sunny skies add a bit of warmth to your skin. And winds are lighter today, around 10 mph from the northwest, with gusts generally less than 20 mph. Areas north of town may see a stray midday flurry or two as a weak disturbance zips by.  Confidence: High

Tonight: Evening temperatures are quick to drop off owing to mostly clear skies and calming winds. Lows range from near 20 in the coldest suburbs to the mid-20s downtown, with increasing clouds possible toward morning. Confidence: High

Follow us on Facebook, Twitter, and Instagram for the latest updates. For related traffic news, check out Dr. Gridlock. Keep reading for the forecast through midweek…

Tomorrow (Monday): Skies may start partly sunny but should turn mostly cloudy as we head into the afternoon. Temperatures head for highs in the low-to-mid 40s again as light winds come from the southeast ahead of our developing storm. We’re not expecting any snow or rain to arrive until after 6 p.m. or so. We encourage you to stay tuned to the forecast during the day tomorrow, when we should have a better idea whether snow might arrive early enough to disrupt the latter part of the commute home.  Confidence: Medium-High

Tomorrow night into Tuesday morning: Snow, or a mix of rain and snow, is likely to move in sometime around 6-9 p.m. from south to north. Accumulating snow is a good bet as the intensity of precipitation increases late evening into the overnight, and lows dip to the upper 20s to low 30s as winds become gusty from the northeast, before the snow tapers early to midmorning on Tuesday. But how much snow is a hard question, and amounts could vary greatly depending on the exact track of the storm and where the rain-snow line sets up. Some sleet is possible as well. Confidence: Low-Medium

Areas north and west of D.C. have the best chance of seeing the most snow. Areas from downtown D.C. to the south and east could also see substantial snow, but they also have the best chance of seeing snow totals reduced by warmer temperatures or the mixing in of rain or sleet.

Below is our first-call snow map. It is truly a first call and could change as more model information comes in today. We’ll have a full update on the storm before noon.


A LOOK AHEAD

As the storm moves away, lingering snow showers or flurries are possible later Tuesday morning into the afternoon. Highs should rise above freezing into the mid-30s to low 40s with lighter winds. But a hard refreeze is expected Tuesday night as lows drop into the 20s, with winds picking up again from the northwest and a few flurries possible from time to time. Confidence: Medium

Wednesday features a bit of energy looping around overhead, and that should keep our skies at least partly cloudy. In addition, a few flurries or even a brief, bona fide snow shower is possible throughout the day. Other than that, it’s a windy and very chilly one, with highs only in the 30s, perhaps not getting out of the low-to-mid 30s. Confidence: Medium

SNOW POTENTIAL INDEX
A daily assessment of the potential for at least 1 inch of snow in the next week, on a 0-10 scale.

9/10 (): At least an inch is looking like a pretty good bet, with much more possible but not certain.

Dan Stillman contributed to this post.