Posted at 6:54 AM on June 23, 2010
by Craig Edwards
Filed under: Rainfall
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.
Posted at 1:29 PM on June 23, 2010
by Craig Edwards
Aided by some sunshine scattered thunderstorms have boiled up around the Twin Cities metro. Some of these storms could produce hail and gusty winds along with brief heavy, big drop rainfall.
A steadier rain has fallen in central Minnesota to the north of the Twin Cities through the morning hours and into the early afternoon.
Posted at 2:08 PM on June 23, 2010
by Craig Edwards
The atmosphere is still producing enough energy to keep showers and isolated thunder dancing acrosss Minnesota. See the regional radar to the right menu.
Copious rain fell on sections of central Minnesota overnight. Four inches accumulated seven miles west of Cambridge with four and a half inches of rain measured three miles west of Kimball in Stearns County.
Improving conditions are expected this evening. More unsettled weather is in our future for later Friday into the weekend.
Most recent image of tornadoes documented by NOAA Weather Service from June 17th.
Details of the tornadoes.
It is not surprising to learn that the number of documented tornadoes is down from the original thirty-six reported as the event was underway. Storm chasers and spotters were well ahead of this big tornado day in Minnesota. I'm sure there were reports of the same tornado touching down just from different viewing locations.
This was not the case very early in my career. When I was in Indianapolis one of my first assignments was to document the tornado tracks in Indiana. Upon my arrival in the Circle City I had a stack of newspaper clippings several inches tall on my desk. All from stories written about March 1976 storms.
Using a manual type-writer and sifting through the numerous reports of citizens filed in the local papers I complied the historical information without the benefit of a ground survey. Many, like the majority of tornadoes today, were F0 or F1s.
On a Sunday in early June 1990 I was working at Indianapolis when a tornao outbreak exploded before our eyes. My best guess is that we had more than fifty reports of tornadoes in the state. By the time we had completed the field surveys, at least on the storms we were aware actually hapened, the number of tornadoes was reduced to about three dozen. Here's the NWS story of the June 2-3, 1990 outbreak.
Finally, I'll share just how far we come with communication and observations of weather. I recall one instance out of rural south central Indiana were I didn't know a tornado had occurred until a weekly newsclipping showed up on my desk about the storm, which had produced damage several days previous.. No one was injured, but I'm sure there was a good yarn shared at the local cafe.