Thunderstorms were a late arrival in Minnesota on Tuesday. While the air mass was juiced up to fire off storms the trigger was jammed. There was a bit a a warm layer at ten thousand feet that capped the instability during the afternoon. This allowed for abundant sunshine and the temperature to climb to ninety or greater in some locations, including the Twin Cities International Airport.
A boundary of convergence, identified as a wind shift line from Hinckley to Willmar, ignited a band of thunderstorms with locally heavy rain overnight. The other region with better upper level dynamics and vertical lift was positioned near the Iowa and Minnesota border where heavy rain also fell last night.
A cold front will displace the warmth of Tuesday and you’ll notice both the change in wind direction and the lowering of the humidity today. Thursday should be quite pleasant.
In the Twin Cities we reached ninety-one degrees late Tuesday afternoon. This was the third time we have reached ninety or greater this year. The warmest reading was ninety-five on May 24th. Climate data suggests that on average we reach ninety or better about thirteen days a year. Last year we had only six days of ninety or more in the Twin Cities, none in the month of July.