Posted at: 10/02/2013 5:32 PM
Updated at: 10/20/2013 7:49 PM
A powerful Fall storm is still lined up for the upper midwest beginning tonight and lasting well into the weekend. A whole range of different kinds of weather are expected, from mild temps and storms to a cold, blustery wind.
A stationary front parked over the area with ample moisture streaming into it from the south will provide the area with several rounds of showers and thunderstorms. Out of this, periods of heavy rainfall. Most areas are looking at at least 1 to 3" of rainfall over a three day stretch from Wednesday night into Saturday night. The Weather Prediction Center estimates rainfall totals from Wednesday night to Saturday night to be upwards of 4" in a few locations.
With mild temperatures hanging around to provide instability, severe weather also looks to be a possibility. There's an isolated risk of seeing a strong to severe storm Thursday, but more probable for Friday afternoon into Friday night as the heart of the storm gets closer.
By Friday evening (image below), that stationary front is still draped right across the local area. And to the southwest the area of low pressure is pulling nearer. With warm, moist air moving up from the south and the clash of cold air approaching from the west should provide the area with a scenario favorable for severe weather development.
Large hail, high winds and even a few tornadoes are possible within the "Slight Risk" area. (yellow shading above)
Timing for the strongest of storms would be from late Friday evening, mainly after 4pm into Friday night.
So will it be SE Minnesota and N Iowa? We can't get too specific right now.
The setup greatly depends on our particular setup heading into Friday afternoon. Exact front placement... Where the surface low is... Temperatures. If temperatures remain cooler from clouds and persistent rain Friday morning, our severe risk will be greatly diminished. Severe Storms need fuel and warm, moist air is the fuel. We'll get a better anticipation of what occurs Thursday night into Friday.
What we can say right now, it's one of the best setups we've seen for severe weather this year. Be "Weather-Aware" with the potential setup for Friday, especially with all the high school football expected and given it's a kickoff to the weekend. Keep tabs on the forecast right from the Storm Tracker 6 Weather Team.
On the back side of this system, the colder air will overtake the area and it will be noticed. By Saturday evening temperatures should be sitting in the upper 40s and lower 50s. It's all coming in on a swift westerly wind which should be around 15-25 mph.
Storm Tracker 6 Chief Meteorologist