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Posted at 05:00 AM ET, 01/30/2012

Forecast: Big midweek warmth, winter weather by the weekend?

Today's Daily Digit
 
A somewhat subjective rating of the
day's weather, on a scale of 0 to 10.

 
45 and dry in late January is nothing to complain about or rejoice over
 
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EXPRESS FORECAST

Today: Partly sunny. 43-48. | Tonight: Mostly cloudy. 33-40. | Tomorrow: Becoming partly sunny, mild. 56-63. | Get Express Forecast by E-mail

FORECAST IN DETAIL

The theme of the winter has been prevailing milder than average conditions with the occasional shot of colder weather. This week: same deal. Today’s actually quite seasonable but temperatures spike Tuesday and Wednesday with 60+ highs possible. Thursday’s rainy and mild before temperatures trend downward, setting the stage for the *chance* of some inclement winter weather this weekend.

Snow Potential Index: 2 (↑) - Winter storminess possible over the weekend, but way more questions than answers on the details at this point.
 
The SPI is a daily assessment of the potential for accumulating snow for the next week on a 0-10 scale. Get the 'SPI' on Twitter
 

Today (Monday): The cold front that passed through overnight drops temperatures back to near normal levels. Under partly sunny skies, highs range from 43-48. A moderate breeze from the west in the morning becomes light in the afternoon. Confidence: Medium-High

Tonight: Clouds increase as a warm front lifts through the region. No precipitation is involved, though. Lows range from near freezing in the colder suburbs to the upper 30s downtown. Light winds become southerly late at night. Confidence: Medium-High

Keep reading to find out when winter finally shows...

Tomorrow (Tuesday): This could be the nicest day of the week. Considerable cloudiness in the morning gradually disintegrates and flow from the south assists temperatures in climbing into the upper 50s north of town to the mid-60s south of town. The risk in this forecast is that the clouds and cooler air hang around longer than forecast, holding highs mainly in the 50s. That risk is highest north of D.C. Winds are from the south and southwest at 10-15 mph. Confidence: Medium

Tomorrow night: An unseasonably mild evening. The continuation of flow from the southwest keeps low temperatures from falling to only around 40 in the colder suburbs with upper 40s downtown. Confidence: Medium-High

A LOOK AHEAD

We’re granted one more unseasonably mild day on Wednesday, but an approaching cold front creates the opportunity for an afternoon shower (20-30% chance). Highs head up into the low or even mid-60s if we get enough morning sun (increasing clouds in the afternoon). The cold front gets hung up over the region Wednesday night, producing mostly cloudy skies and a slight (30%) chance of rain showers late. Lows range from the upper 30s to low 40s. Confidence: Medium

There’s a good (50-60%) chance of rain Thursday as low pressure develops along the front stalled over the region. Clouds and rain hold high temps to around 50, still above normal. Clearing Thursday night, with lows from the upper 20s in the colder suburbs to the mid-30s downtown. Confidence: Medium

High pressure settles in for Friday. Arctic air lurks north and northwest of the region, but remains far enough away for another milder than average day. Under partly to mostly sunny skies, highs approach 50. Increasing clouds Friday night, with lows from the upper 20s to low 30s. Confidence:Medium

The weekend is a huge question mark at this point. While cold air won’t be firmly established over the region, Arctic high pressure might be favorably positioned to supply some cold air for a time if any storminess develops. In other words, we could be faced with anything from a snow event, to a wintry mix to mostly rain to nothing at all. Based on current models, a mix of precipitation may be most likely before changing to rain, but this is a forecast that needs a lot of refinement. While subject to change, I’ll call for a high near 40 both days, with lows in the low 30s. Confidence:Low

By  |  05:00 AM ET, 01/30/2012

Categories:  Forecasts

 
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