(Radio Iowa) – State Climatologist Justin Glisan says what’s called a serial derecho MAY have entered southwest Iowa early this (Thursday) morning, but it’s too early to determine if it fits that classification because — for starters — the storm system is still moving across the state. Plus, the squall line has to stretch for hundreds of miles. “So there are varying definitions either from 250-400 miles in path length and then about 60-100 miles wide and within that path length multiple wind gusts along the path of at least 58 miles per hour,” Glisan said.
“So if all three of those criteria are met, then we can term this a derecho.” The National Weather Service has received a report of grain bins being thrown into the intersection of Highways 34 and 71, near Villisca early this (Thursday) morning. Glisan says a grain bin that’s not full is susceptible to straight line winds. “This is the same thing we saw in the August 10, 2020 derecho, but to a much larger scale back then,” Glisan said, “so if this is termed a derecho, it will be by no means as devastating as the previous August 10, 2020 derecho.”
That derecho caused damage along a 770 mile path and over eight-thousand homes in Iowa were damaged or destroyed. Glisan says today’s (Thursday) storm system was fired by a strong center of low pressure at the Minnesota/Canada border, combined with a cold front that stretched from Canada to the Midwest and unseasonably warm temperatures and moisture in the atmosphere. “We’re in a wave train recently, so we have several disturbances coming across the Midwest,” Glisan said. The storm threat is not over in southeast Iowa.
“We’re seeing sunlight being able to penetrate through the thinning clouds, instability, moisture still ample down that way, so we could see additional strong tornadoes in that part of the state,” Glisan said, “stretching into Illinois and even parts of Missouri.” Glisan is urging Iowans to ensure they have multiple avenues to get severe weather alerts. “Radio, TV, your smart phone app,” Glisan said. “Make sure you check on people who don’t necessarily have all these avenues to get these warnings — and take care of yourself.”
Quarter sized hail was reported in places like Creston and Albia early this (Thursday) morning — golf ball sized hail was reported near Bussey in Marion County.
