Strong wind warning issued for Iowa. What you need to know about timing, impact
Wednesday could be a historic weather day in Iowa, as a windstorm is expected to bring powerful gusts and thunderstorms in the afternoon and evening.
When will severe weather hit Iowa?
South-southwest winds of 30 to 40 mph will enter Iowa. Gusts of 60 to 70 mph are possible Wednesday night, according to the National Weather Service.
As a low pressure system crosses the central plains to the Great Lakes, temperatures will be 25 to 40 degrees above average.
Severe thunderstorms are expected to hit Iowa Wednesday night.
Rod Donavon, chief meteorologist at the National Weather Service in Des Moines, said on Twitter that Wednesday could be a “historic day in Iowa Weather.”
All counties in Iowa except one under severe wind warning
Strong wind warnings have been issued from eastern Arizona and New Mexico to Michigan as a powerful windstorm moves northeasterly over much of the United States
All counties in Iowa except Lee County in southeast Iowa were subject to a high wind warning Wednesday. Lee County was under strong wind watch, as were parts of Illinois and Missouri.
- In southwestern Iowa, the high wind warning was in effect from noon to 9 p.m. Wednesday.
- Areas of central Iowa, including Des Moines, were subject to a high wind warning from noon Wednesday to midnight Thursday.
- Areas of eastern Iowa, including Davenport, were subject to a high wind warning from 3 p.m. Wednesday to 6 a.m. Thursday.
- Red flag warnings were also in effect in southwestern Iowa and southeastern Nebraska due to the dangers of the fires that could break out.
When are strong winds expected?
Winds should gradually increase throughout the day. As of 11 a.m. in Des Moines, sustained winds could be 20 mph and gusts could be 28 mph, according to the NWS. At 5 p.m., sustained winds can reach 30 mph with gusts up to 57 mph. Peak winds are expected to hit at 8 p.m. with sustained winds of 35 mph and gusts of 70 mph.
Power outages expected, travel could be difficult
Destructive winds can knock down trees and power lines, according to the NWS. Power cuts are to be expected. Hot temperatures and low humidity can “contribute to extreme fire behavior,” the NWS office in Omaha said in a warning.
Travel can be difficult, especially for high-profile vehicles like semi-trailers and school buses.
“People should avoid being outside in wooded areas and around trees and branches,” a strong wind warning from the NWS said. “If possible, stay in the lower levels of your house during the windstorm and avoid windows. Be careful if you have to drive.”
Which schools close earlier?
Many school districts in the Des Moines area have announced plans to close early due to the storm.
Following:These central Iowa schools are planning early layoffs due to high wind warning Wednesday
Could there be thunderstorms, tornadoes in December?
Thunderstorms are expected to move quickly through central Iowa from 4 p.m. to 8 p.m. Wednesday. According to the NWS, destructive winds can reinforce strong non-stormy winds.
“The main severe weather threats will be destructive winds and a few tornadoes,” the NWS said in a forecast. “With non-thunderstorm winds already blowing 60 to 70 mph, thunderstorm winds could reach 80 mph or more.”
The greatest chances of severe weather events are found in areas of northern Iowa and southern Minnesota, including Mason City, Fort Dodge, Carroll and Ames, all of which have moderate risk of severe thunderstorms, according to the NWS. . Atlantic, Des Moines, and Spencer all have increased risks of severe weather.
Council Bluffs, Sioux City, and Iowa City all have slight risks of severe weather. Lyon County in far northwest Iowa, Burlington and Davenport all have marginal risks of severe weather.
How do the 2020 echo wind speeds compare to the winds predicted Wednesday?
While the gusts of wind can be damaging, they are not expected to reach the level of the derecho that swept through Iowa in August 2020.
Gusts from a derecho can reach 100 mph, and last year’s derecho in Iowa did just that. There were reports of gusts of over 100 mph in last year’s storm, including a 130 mph gust near Cedar Rapids. Wind gusts around Des Moines have been reported between 70 and 80 mph, according to the weather service.
The weather service classifies storms that have sustained winds of at least 58 mph and left a damage trajectory at least 250 miles long, classified as derechos.