Network News

X My Profile
View More Activity
The new Washington
Post Weather website
Jump to CWG's
Latest Full Forecast
Outside now? Radar, temps
and more: Weather Wall
Follow us on Twitter (@capitalweather) and become a fan on Facebook
Posted at 10:30 AM ET, 07/20/2009

Forecast: Moisture Moving Back Into Town

By Matt Rogers

Humidity hiatus is over; clouds, some showers this week

* NatCast | Outside Now? Radars, Temps & More: Weather Wall *


Today: Party to mostly cloudy. A few showers and a storm? 79-83. Tonight: Mostly cloudy. 30% chance of showers/storms. 65-69. | Tomorrow: Overcast. 40% chance of showers/storms. 76-81. | A Look Ahead


We've been treated to a pleasing spell of dry weather, cool nights and mornings, and very little summer haze and humidity. Changes are afoot this week, though, as high pressure out in the Atlantic and an upper-level area of low pressure in the Ohio Valley join forces to pump considerably more humidity into the area (though not to oppressive levels). Clouds and shower/storm chances should prevent any major heat waves -- at least that part of this particularly "coolish" summer remains the same.

Today (Monday): More clouds than sun today as a more humid flow from the east prevails. Look for highs mainly in the low 80s. A few showers or a stray thunderstorm are possible, especially in the afternoon. But the chance of rain for any given location is only about 30%, so some spots (if not many) may stay dry. Confidence: Medium-High

Tonight: Clouds should continue to dominate and look for a continued 30% chance of showers and thunderstorms. The clouds and increased humidity levels should keep lows from dropping below the mid-to-upper 60s. Confidence: Medium

Keep reading for the forecast through the weekend...

Tomorrow (Tuesday): As light breezes from the east continue to feed moist air into the area, look for overcast skies with a slightly higher chance of showers/thunderstorms (40%). Highs should be in the mid-70s to near 80 around the area. Confidence: Medium

Tomorrow Night: More of the same with clouds and the potential for some showers/storms around the area (40% likelihood). Lows in the upper 60s. Confidence: Medium


Wednesday through Friday should be rather humid with consistently partly to mostly cloudy skies, highs in the low-to-mid 80s, and an ongoing 30% chance of showers and thunderstorms courtesy a series of small disturbances in the atmosphere. The tricky part is estimating exactly when these disturbances will pass through. Lows mainly in the upper 60s to near 70. Confidence: Low-Medium

The coming weekend may continue the work-week theme of clouds and intermittent shower/storm opportunities. Look for highs mainly in the middle 80s -- but some upper 80s are also possible; that would be about normal for this time of year -- and the potential for even higher humidity. Lows should range from the upper 60s to maybe the low 70s. Confidence: Low-Medium

The long-lead outlook beyond this weekend also shows more clouds, showers, and seasonal to slightly below-normal temperatures to end July.

By Matt Rogers  | July 20, 2009; 10:30 AM ET
Categories:  Forecasts  
Save & Share:  Send E-mail   Facebook   Twitter   Digg   Yahoo Buzz   StumbleUpon   Technorati   Google Buzz   Previous: NatCast: Somewhat Muggy. Scattered Shower?
Next: University Release Misleads Media on Climate


Guys - With this cooler than normal summer so far, what does August look like? Also, is there any correlation between cool summers and cool autumns?

Posted by: authorofpoetry | July 20, 2009 9:42 AM | Report abuse

Still nothing showing on the MD drought map (,NE ), but with no rain in almost a month we have to be edging in that direction, even with the wet late Spring we had. I know I'm certainly hoping for some precipitation this week, my garden is thirsty!

Posted by: tagryn | July 20, 2009 10:48 AM | Report abuse


The reason nothing shows up on the drought maps is because we had SO MUCH RAIN from April 10 to June 30. We finally get a dry [and rather comfortable!] month and here comes the "much-needed-rain" crowd back yelling for more! Result: We'll probably be back sitting in the wringing-wet humidity soup from now through Labor Day, if not through much of the post-Labor-Day hurricane season.

Unfortunately we can't seem to get normal Wisconsin weather [one or so rainy day followed by 2-3 dry days before the next storm system arrives] down here...It all seems to be either feast or famine. We either get 3 weeks of drought or 3 weeks of deluge at a time. "Global warming"???

Oh, and, BTW, the timing is off again!!! It's still TWO WEEKS before I have a month or so free of Tuesday night dances!

Posted by: Bombo47jea | July 20, 2009 12:10 PM | Report abuse

Speaking of clouds, below links a short video of some awesome specimens accumulated by a self-described cloud collector.

Posted by: jhbyer | July 20, 2009 12:13 PM | Report abuse

So I have a general question about precipitation probability. I was always told and read that a 30% chance of precipitation means 30% of the area at any given time will see rain. Now you say that any given location has a 30% chance of seeing rain, that tells me that it's not 30% of the area but literally a 30% chance. Can you clairfy this?

Posted by: paul-Sterling | July 20, 2009 12:33 PM | Report abuse


Hi Paul... generally speaking, the percent chance of precipitation is not meant to imply that a given percentage of the area will see rain/snow/ice at any given time, but rather that any particular location in the forecast area has an XX% chance seeing measurable precip. Your confusion -- shared by many -- is why we periodically use language such as that in the forecast above, especially to emphasize the uncertainty when precip. chances are on the low end.

For more on this subject, see our FAQ on this as well as this nice explanation.

Posted by: Dan-CapitalWeatherGang | July 20, 2009 1:19 PM | Report abuse

It may very well not survive the week, but as of now, we're in record territory for the month.

Posted by: CapitalClimate | July 20, 2009 2:16 PM | Report abuse

The comments to this entry are closed.

RSS Feed
Subscribe to The Post

© 2012 The Washington Post Company