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Posted at 09:30 AM ET, 02/22/2013

D.C. area forecast: Cloudy with spotty mixed precipitation today; wet Saturday, nicer Sunday

11:55 a.m. update: Winter weather advisory issued for northern Fauquier, Loudoun and Frederick counties and north and west (see map) for iciness (light sleet and freezing rain/drizzle) through 10 a.m. Saturday. Patchy, light mixed precipitation is moving through the entire D.C. metro region now, but is not heavy enough to cause significant impacts and will move off to the northeast by mid-afternoon. Some light freezing drizzle is possible in the advisory area overnight, and a more steady area of precipitation may start briefly as freezing rain in the advisory area Saturday morning, before turning to plain rain.

9:30 a.m. update: Radar shows only spotty precipitation to our southwest headed towards the region. Models show very low precipitation amounts and what’s heading towards us may largely evaporate in the dry air overhead.

At most, we’re looking at very patchy mixed precipitation, and we expect little or no snow/sleet accumulation. It’s possible some areas receive no measurable precipitation and just some spitting snow flurries, sleet pellets, and/or rain drops. Bottom line: this is a low to no impact event.

EXPRESS FORECAST

Today: Cloudy, light wintry mix. Low-to-mid 30s. | Tonight: Light wintry mix or drizzle. 31-34. | Tomorrow: Cold rain, tapering late. Near 40 to low 40s. | Sunday: Partly sunny, breezy. 44-49. | A Look Ahead | Get Express Forecast by E-mail

TODAY'S DAILY DIGIT

A somewhat subjective rating of the day’s weather, on a scale of 0 to 10


Cloudy, cold, & wet. Not just wet, but the worst kind of wet: a combination of wintry mix & cold rain. Get the Digit on Twitter | Discuss on Facebook

SNOW POTENTIAL INDEX

A daily assessment of the potential for *accumulating* snow for the next week on a 0-10 scale. More info


SPI: 4 (↑) - Might squeeze out a coating or so Friday, then mix. Coastal sys early next week rainy, but we’ll watch it. Get the SPI on Twitter | Discuss on Facebook

FORECAST IN DETAIL

A tricky forecast today. We start cloudy, but by late morning some very light precipitation could start overspreading the area. Patchy mixed precipitation is possible through the afternoon, but some areas see little of consequence. The weekend looks wet on Saturday, but sunshine returns by Sunday. An active pattern continues into next week.

Today (Friday): The remnants of the large winter storm that impacted the central U.S. yesterday impacts our area today. Don’t expect it to pack as big of a punch, however, since it is competing with both dry and warm air aloft. We should get through the morning rush hour mostly unscathed, but precipitation may move into primarily western parts of the area by the second half (8 a.m. or so). We could have a brief period of snow before the changeover to sleet, freezing rain, and rain around early afternoon.

Dry air aloft should keep the precipitation light and mostly spotty, so accumulations of snow plus sleet will likely be a coating or so at worst, with jackpot ‘potential’ around 1”. Afternoon heating is offset, so highs hover not that far from freezing in the low-to-mid 30s. The evening rush hour could be messy with the ongoing wintry mix, so use extra caution on the commute home (update, 9:30 a.m.: we’re now more optimistic there won’t be major issues for the afternoon/evening commute - but keep an eye out for our PM Update, around 3:30 p.m.)! Confidence: Medium

Tonight: The “sleeze” (sleet + freezing rain) potential continues. We likely seesaw between wintry mix and a cold rain as warm air slowly surges northward. The precipitation will likely still be light, so expect only barely measurable amounts of ice or rain. However, with darkness, the odds of slick spots probably increases, especially in untreated areas. Not much of a temperature difference between the daytime and overnight temperatures with lows near or just above freezing expected. Confidence: Medium

For related traffic news, check out Dr. Gridlock. Keep reading for the forecast through the weekend...

Tomorrow (Saturday): The misery continues. Early Saturday morning could still feature some wintry mix potential before the total transition over to a cold rain by mid-morning. Areas north and west of D.C. and especially higher elevations near the Blue Ridge have the highest chance of having a later changeover from wintry mix to rain. The rain continues most of the day with rainfall totals remaining rather low, but perhaps more than Friday. Highs reach the upper 30s-low 40s. Confidence: Medium

Tomorrow night: We may have a shower around into the evening, possibly a snow shower, but we finally start drying out from west to east as the system exits the area. Winds shift around to the northwest and temperatures still hover in the low-mid 30s. Confidence: Medium

Sunday: All the nasty precipitation departs and sunshine returns which will be a nice reprieve from the persistent clouds and precipitation! Skies clear and temperatures shoot for the mid-40s and possibly even approach 50 closer to the District. There is one caveat to the potential nice day on Sunday, and that will be wind. Sustained winds of 10-15 mph, gusting to 20 mph, will make it feel colder. Confidence: Medium

A LOOK AHEAD

Sunday night: The winds die down overnight, leaving us with clear skies. It will be the coldest night of the forecast period with low temperatures dipping down into the mid-and-upper 20s in the western suburbs to nearer freezing for the District and points east. Confidence: Low-Medium

Clouds return Monday as the next system approaches from the south. Daytime temperatures head for the mid-40s across the area, with nighttime temperatures in the low-mid 30s. Precipitation odds increase overnight, when we could see a return of wintry mix or a cold rain, especially areas south and west of D.C. Confidence: Low

Tuesday brings “mild” mid-to-upper 40s. A coastal system could bring another messy day of cold rain and/or wintry mix potential though. It’s too early to determine how much precipitation we could get from this system, or what the dominant precipitation type might be. But given the temperature forecast, rain is favored locally. Confidence: Low

By Kathryn Prociv  |  09:30 AM ET, 02/22/2013

Categories:  Forecasts

 
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