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 11:00 AM ET, 09/27/2010

Hefty rainfall totals possible through tomorrow

By Jason Samenow

* Stormy start to week: Full Forecast | NatCast | Weather Wall *

Projected rainfall totals through tomorrow morning. Source: NOAA's Hydrometeorological Prediction Center.

Through yesterday, the region has received just 0.81" of rain during the month of September, 2.5" below average. Though the immediate metro region is not officially in "drought", the U.S. Drought Monitor does state the region is "abnormally dry". Parts of western Virginia and western Maryland are officially designated drought areas, with isolated locations in severe drought.

Much of the region may make up at least the September portion of the current rainfall deficit in the next 24 hours, with 1-3" of rain forecast.

The cause of the rain is an expansive area of low pressure over the Tennessee Valley which is being fed by a steady flow of moisture from the Gulf of Mexico and Atlantic Ocean.

The highest rainfall totals during the day today should be just west of I-95 with the axis of the heaviest rain shifting east later tonight and tomorrow morning.

Though forecast models are consistently producing generous totals from this storm system, NOAA's Hydrometeorological Prediction Center cautions:

Putting it simply..model [precipitation forecasts] have not been doing very well handling the rainfall with this system to this point in time.

Nonetheless, confidence is high appreciable rain will fall. My thinking is that the region will probably see totals averaging 1.5-2", but would not be surprised to see some spots seeing as little as around 1", with isolated 3+" totals as well.

Today's rainfall records at the three local airports occurred in 1985 when Hurricane Gloria came up the coast. They are as follows:

Reagan National (DCA): 3.17" (1985)

Dulles Airport (IAD): 1.55" (1985)

BWI: 5.00" (1985)

The 1985 DCA and BWI records are probably safe; Dulles could challenge its record.

By Jason Samenow  | September 27, 2010; 11:00 AM ET
Categories:  Floods  
Save & Share:  Send E-mail   Facebook   Twitter   Digg   Yahoo Buzz   StumbleUpon   Technorati   Google Buzz   Previous: Forecast: A soaking, stormy start to week
Next: Tornado warning for Howard Co. until 12:45 p.m.


Hope this rain holds 2gether, got very little last night, only .15". I've now gotten almost .30" so far this month.

Posted by: VaTechBob | September 27, 2010 11:36 AM | Report abuse

Looks like most of the heavy rain will be E of 95 with this batch.
Going 2 end up with 4th or 5th warmest Sept. on record, outside shot at 3rd, depending on temps the next 4 days.

Posted by: VaTechBob | September 27, 2010 11:44 AM | Report abuse


Getting the exact positioning and timing of the heaviest rainfall is pretty tough -- models are all over the map. Though trend will be to shift heaviest rain east with time, probably best just to follow radar.

Posted by: Jason-CapitalWeatherGang | September 27, 2010 11:56 AM | Report abuse

This appears to be the biggest such event in a couple of years...acts a lot like a tropical remnant.

Posted by: Bombo47jea | September 27, 2010 12:14 PM | Report abuse

Looks like my house is under the heaviest rain, here in Brookeville, MD. It is raining pretty hard, and we are just east of a tornado warning, literally 2 miles from it. Looks like we will be getting our first day in the 60s on Sunday!!

Posted by: bastings | September 27, 2010 12:36 PM | Report abuse

A few peeks of sun the last 15 mins. Still waiting for some decent rain amouts.

Posted by: VaTechBob | September 27, 2010 12:40 PM | Report abuse

VaTechBob - It looks like projections for solid rainfall also cover the Roanoke/Blacksburg area this week.. I bet you should see some soon! keep us posted on your observations there.

Posted by: Camden-CapitalWeatherGang | September 27, 2010 1:00 PM | Report abuse

This system is likely the beginning of the "seasonal shift" in the overall jet stream pattern from summer to fall. Hopefully, it will bring some decent rains to the area; especially western Maryland, northwestern Virginia and eastern West Virginia. Those areas have only observed 25-30% of the normal rainfall this summer.

Posted by: WayneP1369 | September 27, 2010 1:20 PM | Report abuse

The comments to this entry are closed.

RSS Feed
Subscribe to The Post

© 2012 The Washington Post Company