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Posted at 10:30 AM ET, 08/19/2009

Forecast: Light at End of Hot & Humid Tunnel?

By Dan Stillman

Not as hot today but storm chances continue

* NatCast | Where's Category 4 Bill? Hurricane Tracking Center *
* Hurricane-Climate Change Debate | Later: To A/C or Not to A/C? *
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Today: Partly cloudy. 40-50% chance of p.m. storms. Upper 80s to low 90s. | Tonight: Showers & storms end. Mid-70s. | Tomorrow: Partly to mostly cloudy. 40-50% chance of p.m. storms. Upper 80s to low 90s. | A Look Ahead


Why should you care about an area of low pressure moving through the middle of the country today? Well, it's this feature that will progress east over the next few days and, if the models are right, eventually steer Hurricane Bill -- currently a Category 4 storm several hundred miles east of the Leeward Islands -- away from the mid-Atlantic (but sending dangerous surf/rip currents in this direction). In the meantime, we stay warm and humid with daily rain chances through Saturday, when a cold front associated with that low-pressure area comes through, likely bringing drier and cooler air for Sunday into next week.

Radar: Latest regional radar loop shows movement of precipitation over past two hours. Powered by HAMweather. Refresh page to update. Click here or on image to enlarge. Or see radar bigger on our Weather Wall.

Today (Wednesday): A sticky day for sure, though not as hot as yesterday's highs that made the mid-to-upper 90s in some spots. Partly cloudy skies should cap highs in the upper 80s to low 90s. After the chance of a stray shower during the morning hours, some showers and storms are likely to be around during the afternoon into early evening, with a decent chance (about 40-50%) of any given location getting wet. Confidence: Medium

Probability: 40-50%
Coverage: Scattered

Tonight: Any showers and storms should dissipate during the early evening, leaving behind partly to mostly cloudy skies and another muggy night with lows having a hard time making it much lower than the mid-70s. Confidence: Medium-High

Keep reading for the forecast through the weekend. And before you begin your commute home this afternoon or evening, check in with our PM Update for the latest forecast....

Tomorrow (Thursday): Mother Nature's feeling monotonous these days and wants to do today's forecast all over again tomorrow, except maybe with even more clouds: Partly to mostly cloudy and humid with highs in the upper 80s to low 90s and a 40-50% chance of afternoon/evening showers and storms. Confidence: Medium

Tomorrow Night: After the chance of scattered evening showers and storms, just an isolated shower or storm overnight. It'll be super-muggy with lows once again only dropping to the mid-70s. Confidence: Medium


The way it looks now, a cold front will take its sweet old time approaching from the west on Friday. Out ahead of it, we could see scattered showers and storms, especially in the afternoon into Friday night. Highs should again top out in the upper 80s to low 90s along with some pretty intense humidity. Confidence: Medium

Can't say exactly where that cold front will be on Saturday, but I think it'll be close enough to keep things rather cloudy and continue our shower and storm chances with highs in the 80s. Humidity? Probably still on the high side, but could ease a bit during the day if some drier air can work its way in behind the front. Diminishing shower and storm chances Saturday night with lows in the 60s to near 70. Confidence: Low-Medium

Current indications are that the front will sag far enough to our south to allow for increased sun on Sunday with decreased humidity and highs in the 80s. I'll leave the chance of an isolated shower or storm in the forecast for now, but we might be able to remove even that if the models continue to trend drier and sunnier. Confidence: Medium

By Dan Stillman  | August 19, 2009; 10:30 AM ET
Categories:  Forecasts  
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Next: To A/C or Not to A/C? That is the Question.


Quite a spread in NWS and your precip forecasts for today/tonight. 30% vrs 70%. Wildly different interpretations or are forecasts using different data (earlier/later)?

Posted by: GISman | August 19, 2009 10:31 AM | Report abuse


Where do you see 30%? Forecast above shows 40-50%, which actually seemed like it may be too high based on the overnight models, which decreased the precip. potential a bit. But the latest data looks more promising for some showers and storms, still supporting the 40-50% probability that any one location gets wet.

We do have 30% in our NatCast, but that forecast is for approximately 7-10 p.m., when shower/storm chances will be diminishing.

Posted by: CapitalWeatherGang | August 19, 2009 11:02 AM | Report abuse

downtown clouds, wow, they are looking ominous with signs of serious cumulus turbulence! (updrafts & downdrafts)

Posted by: Camden-CapitalWeatherGang | August 19, 2009 11:29 AM | Report abuse

The nat cast I assume jives in time period for the Wednesday night forecast of 70% by NWS. That was to which I was referring. When does a NWS night forecast come into effect? I assumed it would be around the 6-7 time period.

Posted by: GISman | August 19, 2009 12:12 PM | Report abuse

Sky conditions seem to vary anywhere from clear to threatening today. We had a bit of rain in the past 30 minutes. Lots of well-defined cumulus.

Bill is now at 140 mph Category 4. Biggest threats seem to involve Bermuda, Nova Scotia and Newfoundland; storm will have weakened to around Category 1 as it threatens Canadian coasts. Surf will be big threat to our coast.

Posted by: Bombo47jea | August 19, 2009 12:49 PM | Report abuse

Dark, rumbly, and raining heavily in Lake Ridge.

Posted by: meta2 | August 19, 2009 2:51 PM | Report abuse

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