Severe Thunderstorms With Damaging Winds Threaten the Northeast into Monday Evening

July 25,2016
Severe thunderstorms with damaging wind gusts will sweep through a broad swath of the sweltering Northeast into Monday evening.
(MORE: Dangerous Heat Continues)
NOAA's Storm Prediction Center has issued the following severe weather watches:

• A severe thunderstorm watch valid until 8 p.m. EDT for much of southern New York, Pennsylvania, New Jersey and southwest Connecticut, including the New York City and Philadelphia metro areas.
• A severe thunderstorm watch valid until 10 p.m. EDT for parts of southern New Jersey, Delware, Maryland, D.C., northern Virginia and the eastern West Virginia panhandle.

Current Radar, Watches and Warnings

In addition to the threat of damaging winds from today's storms, airport delays in the major Northeast hubs may become significant by evening. Check your flight status before leaving for the major NYC airports, Philadelphia, Baltimore-Washington International, Dulles, or Reagan National Airport.
If that wasn't enough, torrential downpours may cause flash flooding early this week, as these storms will have plenty of moisture to work with.
Below are more details on the forecast early this week.

Thunderstorm Forecast

Into Monday Evening

• Forecast: Severe storms will be most numerous in the afternoon and evening in the Northeast and Mid-Atlantic states. More widely-scattered severe storms in the Ohio Valley. 
• Impacts: Damaging straight-line winds will be the main threat, with downed trees and power outages possible. A tornado or two cannot be ruled out in parts of New York state, but the overall threat is low.
• Cities: Pittsburgh | Philadelphia | New York City | Baltimore | Columbus, Ohio

Thunderstorm Forecast into Monday Evening

Storm Reports

Sunday
Strong to severe storms caused some damage in Chicago Sunday evening, including the damage seen below at the Ashland/UIC Medical Blue Line train stop.
(MORE: Train Platform Damaged, CTA Service Suspended in Strong Chicago Storms)

Winds gusted to 74 mph at Denver International Airport, and a greenhouse was flattened due to the strong winds in Byers, Colorado.
Saturday
Storms raced southeastward across New England resulting in dozens of wind damage reports in Vermont and New Hampshire.
One person was killed in Hubbardton, Vermont when trees were knocked down.
One person was injured in Luzerne, New York when trees fell on their home.
For more information about these reports, please see our impact article.
Wind gusts of 65 to 80 mph were reported from Independence to Buchanan, Iowa as severe storms marched through eastern Iowa.
Friday
Scattered severe storms crossed through the Dakotas during the evening on Friday bringing large hail and gusty winds. In Meadow, South Dakota wind gusts of 90 to 100 mph were recorded. In Firesteel, South Dakota hail in excess of 2.0" in diameter fell.
Two tornado were confirmed in eastern Washington state by the National Weather Service. One was near Airway Heights and the other near Mold. Both were rated EF-0.
Thursday
Early Thursday morning, severe storms moved through Duluth, Minnesota, where trees and power lines were knocked down. In northern Wisconsin, winds gusted to 75 mph in Ashland.
Later Thursday, the severe threat shifted south and east into southern Wisconsin and northern Illinois. Construction damage was reported on the University of Wisconsin-Madison campus due to 60 mph wind gusts from the storms.  
Ridge Rider Pattern Triggers Storms

Disturbances in the middle portion of the atmosphere ride along the northern periphery of the hot high-pressure system.

A massive ridge of high pressure aloft (bulge in the jet stream) is anchored across a large portion of the nation. Locations underneath this ridge will have a low chance for thunderstorms.
A couple of strong disturbances often called "ridge riders" by meteorologists will move across the top of this ridge, however, and they will produce thunderstorms and some will turn severe.
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