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Posted at 04:14 PM ET, 07/01/2012

Update: A few late night showers and thundershowers, severe weather stays southwest

12:15 a.m. update: A few showers and thundershowers will cross the area over the next few hours. No severe weather is currently anticipated with this activity, but brief heavy downpours as well as potentially dangerous lightning will be possible. This will be our final update of the night unless weather warrants.

10:15 p.m. update: Severe thunderstorm watches have crept closer to the area, but storms in line to impact the D.C. area have largely weakened or fallen apart. There is still some potential for storminess overnight, but ingredients for significant severe weather have diminished significantly. Strong and severe storms are more likely to the southwest of the area, where they remain more intense.

8:45 p.m. update: Line of storms are now entering West Virginia. Assuming they hold together, they probably won’t arrive in the D.C. area until 12-3 a.m. This does NOT look like a repeat of Friday (less CAPE), but downpours, lightning and some gusty winds are possible. The Storm Prediction Center is considering issuing a severe thunderstorm watch into western Virginia at this time.

7:00 p.m. update: The cluster of storms that originated around Chicago has entered central Ohio (see regional radar) and remains potent. Severe thunderstorm watches have been issued as far east as central West Virginia. The possibility of intense storms - most likely after 11 p.m. - continues. We will keep you posted.


A slight riskfor severe weather for the rest of the day covers most of the region.

From 4:15 p.m.: After yesterday’s mini reprieve following the severe derecho on Friday, a resurgence of higher humidity mixed with record (96 at Dulles) and near-record temperatures around 100 degrees has helped promote a volatile environment over the area.

Add in a new thunderstorm complex well to the northwest that has already caused at least 200,000 outages in Chicago, as well as a slight risk for localized pop-up storms, and we’ve got a few concerns to keep an eye on for the rest of the day.

Taking these factors into consideration, The Storm Prediction Center recently added our area into a “slight risk” of severe storms, including the threat of damaging winds and large hail. At this point, should they threaten, the storm risk seems to be greatest from the hours after sunset through about 2 a.m.

Overview

Right now, it’s quite uncertain whether the system that has impacted Chicago with severe wind gusts will even continue to grow as it heads east. However, indicators such as CAPE (see how much there was Friday) are running on the high to extreme level out ahead of the storms, in a line across the Ohio Valley pointed toward parts of West Virginia.

Given that potential, stacked with similar values from other indicators, at least the short-term would tend to favor severe weather moving east over those regions.

But — if the storm complex survives and/or grows — where does it go once nearing our area?

Steering winds are currently pushing the storms east-southeast toward the Appalachians. This puts spots like Ohio and West Virginia, where strong instability will be in place, potentially directly in the line of fire.

Related: Great Lakes Radar

From there, it’s a little less certain as winds aloft want to turn a bit more to the due east in our direction. Should that happen, indications are that we’ll have plenty of juice for them to feed off of. Damaging winds, large hail and dangerous lightning would all be in the cards heading into the night.

Model guidance and live trends suggest we’re more likely to get clipped (if that) than take a direct hit, with the brunt heading south of the area. But, as with Friday, pinpointing exact locations of possible dangerous weather is tricky even in the hours leading up to it.

It’s also possible these storms just fall apart. Winds aloft are not quite as favorable as Friday, and other ingredients are all generally less. Should a strong line move toward us, or others pop up in more random fashion, we’ll want to pay attention given the ingredients available, especially with the cleanup still ongoing.

We’ll keep you updated as the day progresses, both here and on Twitter and Facebook. And check out the forecast into the work week.

By  |  04:14 PM ET, 07/01/2012

Categories:  Forecasts

 
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