A rather juicy atmosphere will interact with a storm system moving in from the Dakotas. This is expected to allow supercells to develop in western Iowa this afternoon. There are some uncertainties as always with this system so let’s break this threat down…
Taking a look at the graphic to the right, you can see the tornado threat for today. You’ll notice a pretty high risk for the western third of Iowa, sharply falling off as it moves to the east. This is because the best chance for a tornado outbreak lies in the area the first discrete supercells develop, likely in western Iowa and southwest Minnesota.
As storms continue to increase in size, the primary threat will shift over to a strong damaging wind event. This could produce the most widespread damage with this storm.
Of greater concern is the duration of this event. The primary risk for tornadoes should last for approximately 3-4 hours before strong winds become the predominant threat. When all is said and done, the threat of severe weather could begin around 3pm and last well into Friday morning.
Chase teams will undoubtedly focus on western Iowa. We’ll continue to debate our move as the event draws closer and provide updates throughout the day as new information comes in.