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Posted at 05:00 AM ET, 01/31/2012

Forecast: Big warming today and tomorrow; cooler weekend, possibly inclement

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

 
Knocking two points off for snow-lovers (me included) who see another wasted winter day. But if it's going to be warm, it might as well be really warm!
 
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EXPRESS FORECAST

Today: Some AM clouds. PM sun. Oh. So.Warm. 60-66. | Tonight: Partly cloudy. 40-49. | Tomorrow: PM shower chance. Still mild. 62-68.| Get Express Forecast by E-mail

FORECAST IN DETAIL

Our winter-free winter marches onward with another impressive surge of very warm conditions over the next 48 hours. Low pressure is tracking way far north along the U.S./Canadian border, which easily puts the mid-Atlantic in the “warm sector” through Wednesday. I really wouldn’t be surprised if we see 70-degree readings somewhere between Richmond and here before it trends cooler and wetter on Thursday. The weekend shifts colder, but it is not clear yet how much colder. The best guess right now is mainly weekend clouds and a chance of rain showers.

Snow Potential Index: 2 (→) - Weekend snow odds not promising but lots of uncertainty still so we'll keep the SPI at a low level.
 
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 (Tuesday): For weather forecasters, it is always good to look out the window and also to peer at the weather occurring to our west. Yesterday, temperatures got warmer than expected in many areas from St. Louis to Cincinnati. Therefore, we should probably aim higher on today’s temperatures. After some scattered morning cloud cover, expect the sun and winds from the southwest (5-10 mph) to pump us up into the low-to-mid 60s. Some areas could inch a degree or two higher even. It will certainly not feel like the calendar. Confidence: Medium-High

Tonight: Partly cloudy skies and a mild air mass means the best we can do tonight is probably the 40s for lows (closer to 40 in the outer suburbs and the upper 40s in the city). Light winds. Confidence: Medium-High

Keep reading for the forecast through the weekend...

Tomorrow (Wednesday): Usually a second day of warm advection into our area pushes temperatures even higher than the first day, but we have a complicating factor of more afternoon clouds and some afternoon shower chances (just 20%) due to a weak, dying cool front. I believe we’ll be able to get well up into the 60s again with maybe even upper 60s from the city southward. Confidence: Medium-High

Tomorrow night: Mostly cloudy and still mild with lows in the 40s again and a chance for showers toward dawn (~30%). Confidence: Medium-High

A LOOK AHEAD

Thursday finds another atmospheric visitor in this very active weather pattern. A weak disturbance flies through the area, offering showers (60% likelihood) and keeping the sky overcast. The combination of clouds and rain hold our temperatures down in the 50s (mainly low-to-mid). Thursday night finally features some modest high pressure from the north bringing a bit more cold into the area. Skies generally clear as we see lows from the upper 20s in the colder suburbs to the mid-30s in the city. Confidence: Medium

Friday will watch high pressure lumber by to our north. This should keep us under partly to maybe mostly sunny skies, but temperatures will not move as much with highs in the upper 40s to low 50s. Hey, it could still be a lot colder this time of year. Friday night sees a cloud rebound with lows dropping mainly in the 30s, but some 20s in the outer suburbs. Confidence: Medium

The weekend features the approach of a warm front with several impulses of low pressure expected to influence our region. Now, if high pressure were stronger, this situation would offer all sorts of mischief with snow, sleet, and freezing rain chances. But most of our guidance right now suggests that the incoming warming from the south is strong enough, while cold from the north is weak enough to keep us mostly rain. This situation is still uncertain and bears watching. We cannot totally rule out frozen precipitation but favor a warmer scenario at the moment.

Look for rain chances on both Saturday and then again Sunday afternoon into evening (around 40% at this early stage). It doesn’t look like a continuous rain and some parts of the weekend may not be all bad. Highs should range through the 40s into maybe the low 50s with lows in the 30s to 40s (partly cloudy Saturday night). Confidence: Low

By  |  05:00 AM ET, 01/31/2012

Categories:  Forecasts

 
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