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Posted at 5:20 PM ET, 08/19/2009

PM Update: Showers and Storms Into Evening

By Ian Livingston

Tropical conditions persist on Thursday, some rain too

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Scattered showers and storms that developed midday continue into early evening. It was another hot and muggy one as most spots rose to highs in the upper 80s and lower 90s, but there's a decent range of temperatures depending on where rain has fallen. Though showers and storms are possible across the entire area, the focus appears to be on the southern half for the rest of the day. Isolated severe weather has occurred over southern Maryland where a tornado warning was issued and has expired for St. Mary's County.


Radar: Latest D.C. area 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.

Through Tonight: Scattered showers and thunderstorms continue into evening before waning. High humidity levels keep temperatures from falling off too much, like last night look for lows from the lower 70s in the suburbs to mid-or-upper 70s in the city.

Tomorrow (Thursday): Thursday should be pretty similar to today, with partly sunny skies early transitioning to mostly cloudy during the day as showers and storms threaten again by afternoon. Highs should get into the upper 80s and lower 90s depending on cloud cover and any rain that falls. Humidity remains quite high.

See Dan Stillman's full forecast through the weekend. And if you haven't already, join us on Facebook and follow us on Twitter.

Camille 40 Years Later: Much has been written and observed about Hurricane Camille making landfall on the Gulf Coast 40 years ago this week, but impacts nearby were severe as well. Rick Schwartz takes a closer look at the record-breaking rainfall over portions of Virginia that fell on August 19 and 20, two days after the storm made landfall and had been generally dissipating.

By Ian Livingston  | August 19, 2009; 5:20 PM ET
Categories:  Forecasts  
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Next: NatCast: Sticky Weather. A Passing Storm?

Comments

it is sooo humid out today...

Posted by: madisondc | August 19, 2009 3:37 PM | Report abuse

Big storm running South of the beltway. Commute fail...

Posted by: JJones-CapitalWeatherGang | August 19, 2009 3:39 PM | Report abuse

Re: Camille

If interested, here's a photo of the washed out Tye River trestle. All that was left was the rails.

Here's a couple more showing the washouts caused.

Posted by: spgass1 | August 19, 2009 4:12 PM | Report abuse

Deluge about an hour or so ago in Lake Ridge ~ 1.5 + inches.

Posted by: ZmanVA | August 19, 2009 4:22 PM | Report abuse

Looks like some areas are getting a real storm. Another bust for for the Dulles area.

Posted by: LoudounGeek | August 19, 2009 4:27 PM | Report abuse

i saw a report on noaa of golfball to baseball size hail in leonardtown anybody can anyone out there confirm that, sounds crazy

Posted by: billy12 | August 19, 2009 5:33 PM | Report abuse

billy12, There is a spotter report of "Ping pong to baseball sized hail". Vertically integrated liquid values spiked (see image) on that storm as it was passing through and tornado warned. Nice little hook echo too (see image). Both radar grabs from wunderground.com

Posted by: Ian-CapitalWeatherGang | August 19, 2009 5:51 PM | Report abuse

spgass1, just looked at those links. cool, thanks!

Posted by: Ian-CapitalWeatherGang | August 19, 2009 5:58 PM | Report abuse

That severe storm in St. Mary's county was a real surprise. The dynamics today, despite a lot of heat and humidity, just did not favor severe weather. The air was extrememy moist at all levels (you could tell from the fuzzy Pileus on the cloud tops) and this morning's sounding showed over 2" of precipitable water, with dew points above 70. There was also a slow lapse rate, little and no wind shear or dry air at mid-levels....you generally want a steep lapse rate and dry air/veering winds aloft for large-hail, downbursts, or tornadic storms. Conditions like today usually produce tropical-type thunderstorms with several inches of rain and without a lot of strong winds or lightning.

So, I don't see how we got such a strong rotating storm and large hail down there....but, of course, Dopplers and severe-storm spotters don't lie.

Posted by: MMCarhelp | August 19, 2009 6:08 PM | Report abuse

At the time of the tornado warning and hail, Doppler was indicating tops around 55k with that cell (supercell) near Leonardstown, the others were generally more modest.. Satellite shows a nice overshooting top with that storm. I would guess the fact that it was able to get that tall played some role. Rotation looks to have been strongest right near the bay so I wonder if there was interplay there. It has been known to happen in other places with the surface wind shifts and all.

Posted by: Ian-CapitalWeatherGang | August 19, 2009 6:27 PM | Report abuse

82 degrees and it feels really sticky for a late afternoon in august (72 dewpoint).

Posted by: jojo2008 | August 19, 2009 7:14 PM | Report abuse

The comments to this entry are closed.

 
 
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