Severe Weather Outbreak Winds Down Across Midwest, Great Lakes

November 11,2015

At least 10 tornadoes have been reported, one of them damaging buildings in an Iowa town and another striking Iowa's busiest airport, as severe thunderstorms continue to race across parts of Midwest.
(MORE: Damaging Storms Strike Several States)
In addition to the severe thunderstorms, the area of low pressure has generated blizzard conditions in parts of the High Plains and a large area of strong winds not associated with thunderstorms in the Plains that will spread east through late this week.
There have been at least 10 reports of tornadoes or tornado damage as of Wednesday night. This total includes one EF-1 tornado confirmed by a National Weather Service survey near Avoca, Iowa. There have also been at least 75 reports of thunderstorm wind damage, mainly in Iowa, Missouri and Illinois.
Peoria, Illinois, clocked a 71-mph wind gust at 7:44 p.m. CST Wednesday, breaking its all-time November wind gust record of 70 mph set during the Nov. 17, 2013, tornado outbreak.

Radar, Watches & Warnings

Below are radar maps focusing on areas with the best chance of severe thunderstorms or flash flooding, either currently or during the forecast period. The maps update every 5 minutes; refresh your browser for the latest image.
Hollow red outlines denote tornado warnings, while yellow outlines denote severe thunderstorm warnings. Larger areas of solid light-red shading are tornado watches, while larger areas of solid light-yellow shading are severe thunderstorm watches. All watches and warnings are issued by the National Weather Service.
(MORE: View National Interactive Radar Map | Difference Between a Watch and a Warning)

Current Radar with Watches & Warnings

Current Radar with Watches & Warnings

Forecast: Severe Weather Outbreak Ending

Short-Term Thunderstorm Forecast

Thunderstorms Wednesday took advantage of a combination of somewhat unstable air and very strong wind energy. The instability was the product of unseasonably warm and moist air being pulled north into the Midwest by the parent low-pressure system, and the wind energy is a reflection of the strength of the storm system swinging through the nation's midsection.
As those thunderstorms continue to race east, they are encountering more unstable air. That will make it much more difficult for them to pull down the wind momentum higher in the atmosphere and transfer it to ground level where it can do damage.
In fact, the lack of instability will choke off the storm system's ability to generate thunderstorms at all, though a narrow band of heavy rain may still persist ahead of the main cold front and that could still bring a brief burst of strong gusty winds.
Overall, the threat of damaging thunderstorm winds will decrease through the overnight.
(MORE: Where November Tornadoes Are Most Common)
Here is our latest forecast thinking.

• Overnight: A squall line of rain showers without much lightning, will shift east across the Great Lakes region. Due to stable air, the threat of wind damage will diminish. However, strong winds still accompany the parent storm system, and even without thunder and lightning, heavy squalls of rain may be able to bring some locally strong, gusty winds.
• Thursday: Probably no severe thunderstorms as the weather system heads east into stable air.

For specific tornado threat forecasts, check out the latest TOR:CON forecasts from severe weather expert, Dr. Greg Forbes.
Severe weather and tornado outbreaks are not unusual in November. In fact, November is a climatological "second season" of severe weather, not simply in the Deep South but, occasionally, in parts of the Midwest.
Almost two years ago, an outbreak of 72 tornadoes raked through parts of seven states, including a pair of EF4 tornadoes in Washington, Illinois, and near New Minden, Illinois.

PHOTOS: Tornadoes, Flooding in the South (Late Oct. 2015)