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Posted at 10:00 AM ET, 01/28/2013

D.C. area forecast: Icy start to wildly volatile weather week

* Winter weather advisory through noon for D.C.’s northern suburbs | Wintry mix prompts delays | Federal offices to open at noon *

Temperatures: Latest D.C. area temperature map. See interactive map on our Weather Wall.

10 a.m. update: The winter weather advisory has expired except for Loudoun, Montgomery, Howard, Baltimore, Carroll and Frederick counties where it continues until noon. Inside the beltway, precipitation has changed to plain rain. Mainly north and well west of the beltway, some patchy freezing rain continues. Walking continues to be the main hazard, with lots of falls reported on our social media feeds, even in downtown D.C. Ice should gradually melt between now and noon, southeast to northwest and precipitation should end.

EXPRESS FORECAST

Today: AM light freezing rain to rain, then cloudy. Near 40. | Tonight: Slight chance of light rain. Near 40. | Tomorrow: Mostly cloudy, 47-55 . | Get Express Forecast9 by E-mail

TODAY'S DAILY DIGIT

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


A little icy then a lot raw. What’s to like? 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: 2 → A couple weak disturbances between Friday and Sunday have dusting-type potential. Get the SPI on Twitter | Discuss on Facebook

FORECAST IN DETAIL


This week’s weather, plainly stated, is kind of nuts. We start with some possible iciness this morning. Then temperatures spike, climbing into the 50s Tuesday and 60+ Wednesday. After a possible round of gusty showers or even thunderstorms to close Wednesday, temperatures crash and highs are back in the 30s for the coming weekend.

Today (Monday): Be very careful for possible icy sidewalks and side roads if you’re headed out early. Allow extra time for travel or consider delaying (OPM is asking federal workers to stay off roads until 10 a.m.). While sleet and/or freezing rain is probably just light and patchy and favored in our colder suburbs, it just takes a thin glaze for hazardous conditions with the cold ground. Temperatures edge above freezing from southeast to northwest between 7 a.m. and 10 a.m. allowing any freezing rain to become just plain rain. Also, look out for some pockets of fog.

During the afternoon, there’s just a small (30-40 percent) chance of light rain, with highs 38-43. Winds are from the south at around 10 mph. Confidence: Medium

Tonight: The warm front responsible for the wintry mix will have lifted to our north, but hangs around close enough that we might see a few more showers overnight (30 percent chance). Otherwise, it’s cloudy with near steady temps around 40. We may see some fog develop. Confidence: Medium

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

Tomorrow (Tuesday): Although the warm front will have moved through the region, a shallow cool wedge may try to slip south complicating the forecast. Although this is a pretty weak wedge, it may stall temperatures in the mid-to-upper 40s in our northern suburbs. Locations from the District south should see temperatures climb to near 50-55 unless the wedge penetrates further south than forecast. Sky conditions are mostly cloudy early (with patchy fog possible), with the best chance of sunnier skies during the afternoon. Confidence: Low

Tomorrow night: It’s mostly cloudy and unseasonably mild. Winds from the south mean lows only in the upper 40s to low 50s. Confidence: Medium

A LOOK AHEAD

A big push of unseasonably mild air from the south Wednesday elevates the mercury to 60 or perhaps a bit higher if we can manage some sunshine. But a cold front approaches late with a line of showers and possible thunderstorms, which may be heavy and even produce some strong winds. After evening showers and storms, it turns windy and cooler with lows 35-40 (suburbs-city). Confidence: Medium

Thursday’s partly sunny, windy and much colder, with highs not making much headway from morning lows, only reaching the upper 30s to low 40s. Partly cloudy, not as windy, but cold Thursday night, with lows in the 20s. Confidence: Medium

A weak disturbance swings by Friday, which may set off some snow showers or flurries, especially in the afternoon/evening. Highs are mostly in the low-to-mid 30s. Partly cloudy Friday night, with lows in the upper teens to mid-20s (downtown). Confidence: Low-Medium

Much like the weekend that preceded it, the coming weekend looks cold, with highs mainly in the 30s and lows in the 20s. We *might* see a period of snow showers or flurries late Saturday night into Sunday morning as another weak disturbance swings by. Confidence: Low-Medium

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Monday morning wintry mix updates, which are no longer relevant

8:50 a.m. update: Radar continues to show light freezing rain and light rain streaking into the area from the west, but it does begin to taper off in eastern West Virginia. The main issues this morning seems to be sidewalks, which are very slick and require extreme caution. Conditions should slowly improve in the next couple of hours as temps slowly rise and precipitation wanes.

7:00 a.m. update: Depending where you are, freezing rain or just plain rain is falling. Temperatures remain between 30-34, with locations mainly west and northwest of the beltway below freezing.

The general consensus is that it’s not all that bad out there. Yes, some sidewalks and side roads are a bit slick (be careful *walking*) , but main roads are reportedly in very good shape. Best bet is to allow extra time and take it easy, but if you need to be somewhere, you should be fine.

In the next 1 to 3 hours, temperature should rise above freezing where they aren’t already (taking longest well to the northwest from Leesburg to Frederick and west) while the coverage and intensity of precipitation diminishes.

6:20 a.m. update: Rain and/or light freezing rain continues (mixing with sleet and snow well north and northwest of D.C.), temperatures range from 30 in the colder suburbs to 34 downtown (where just plain rain is falling). Reports from readers indicate main roads are not bad, but some slick spots can be found on side roads and sidewalks, especially north and northwest of the beltway. Use caution when venturing out.

5:40 a.m. update: A light mix of snow, sleet and freezing rain has moved into the area. In most spots, precipitation began as snow but quickly transitioned to sleet and freezing rain. Temperatures are hovering right around freezing (30-34 degrees) throughout the region, meaning slick spots on sidewalks and side roads are likely. Temperatures will hold steady for the next couple hours before gradually rising above freezing.

By  |  10:00 AM ET, 01/28/2013

Categories:  Forecasts

 
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