/Issued 5:49 PM CDT, Wednesday, September 21, 2016/
Upper Midwest radar loop ending at 5:30 PM CDT today. Source, WSI.
Showers and thunderstorms continue to develop late this afternoon south of Highway 2 in northeast Minnesota and northwest Wisconsin. Northern Minnesota, Arrowhead and most of the North Shore should remain dry tonight.
Flash flood watch continues tonight and Thursday in much of southern and parts of eastern Minnesota thru much of western, central, eastern and southern Wisconsin.
Light green areas are active flood warnings as of 5:30 PM today.
Orange areas are active severe thunderstorm warnings as of 5:30 PM today.
Visible satellite image, surface temperatures and warm front location (Red line on map) from 2 PM today. Source, http://weather.cod.edu/forecast/
Source, Weather Prediction Center.
Tonight's low temperature forecast. Source, TropicalTidbits.com
Thursday's high temperature forecast. Source, TropicalTidbits.com
The computer models look a little interesting for next week but will see how they look a few days from now. Potential is there for a large low pressure system that may cutoff for a few days somewhere from the central Plains to the northern Plains or Upper Midwest.
Jet stream on September 20, 2016.
Jet stream forecast this weekend.
*Local Storm Reports for September 21, 2016*
Source: National Weather Service Duluth, Minnesota
*4:54 PM CDT: HAIL. 0.25 inch diameter. S Breezy Point, MN (Crow Wing County)
*4:40 PM CDT: HAIL. 0.75 inch diameter. 10 S of Aitkin, MN (Aitkin County) Hail fell from 4:36 PM to 4:38 PM.
*3:11 PM CDT: HAIL. 0.25 inch diameter. 7 WNW of Phillips, WI (Price County)
Weather Summary for northeast Minnesota and northwest Wisconsin
Date: September 21, 2016
A setup that we have seen play out several times during the past few months is back on this final official last day of summer 2016 - A strong warm front has moved into southern Minnesota today with high pressure stretching from Alberta Province to western Ontario Province Canada. Deep tropical moisture consisting of 65-70+ degree dew points covered southern Minnesota this afternoon while a much drier airmass with dew points in the 40s covered northern Minnesota. Late afternoon PWATS ranged from ~1.00" in northern Minnesota to between 1.50-1.70" over central, eastern and southern Minnesota. The temperature contrast is also impressive today with highs in the 60s over the Northland which is average for this time of year while mid 80s and low 90s were common in parts of southern Minnesota which is well above average for late September.
Earlier today an area of rain showers moved through far northern Minnesota with rain totals generally ranging from a trace to around 0.05".
Showers and thunderstorms have been blossoming this afternoon from east central Minnesota into northwest Wisconsin as the mid level warm frontal boundary lifts north into central Minnesota. These storms have been producing frequent lightning along with heavy downpours.
Forecast Discussion for northeast Minnesota and northwest Wisconsin
.Short Term Forecast...
The basic weather setup through Friday will feature a warm front which will extend from northern Iowa/southern Minnesota into central Wisconsin with strong high pressure over central Canada.
Tonight (September 21)
Showers and thunderstorms should continue most of the night from east central Minnesota into northwest Wisconsin - These storms will be capable of producing heavy rain along with a lot of lightning. There is also a decent amount of elevated CAPE in that area late this afternoon with values at around 1000-1500 j/kg along with very steep mid level lapse rates of 7.0-8.0 c/km and 40-50 knots of deep layer wind shear...A few of the storms especially this evening could spit out some hail possibly near severe criteria 1.00 inch diameter (quarter size)
Northern Minnesota and the Arrowhead should stay dry tonight under partly to mostly cloudy skies.
A wide range in low temperatures tonight with 40s in far northern Minnesota to around 60 degrees in parts of northwest Wisconsin. Winds will remain out of the east or northeast at 5 to 15 mph with higher gusts near Lake Superior.
Thursday (September 22)
Showers could continue in parts of east central Minnesota and northwest Wisconsin on Thursday but the potential for heavier rain and thunderstorms will be much lower tomorrow vs. this evening. Dry weather ought to continue across northern Minnesota.
Highs on Thursday will be in the 50s and 60s with 70s possible in far southern portions of northwest Wisconsin. Lows Thursday night will be in the 40s and 50s. Winds will be out of the east or northeast at 5 to 15 mph with higher gusts near Lake Superior.
Friday (September 23)
A chance for showers as low pressure heads into the western High Plains while a warm front begins to lift slowly toward the north out of southern Minnesota. Highs on Friday in the 50s and 60s with lows in the 40s and 50s.
Saturday and Sunday (September 24-25)
Occasional rain this weekend but most of Saturday might end up dry with rain chances increasing by Saturday night. Slow moving area of low pressure will be tracking through the northern Plains while a cold front moves E/NE into the Upper Midwest. Highs on Saturday are forecast to be in the 60s and 70s with 50s near Lake Superior. Highs on Sunday are expected to be in the 50s and 60s.
Forecast for Duluth and Superior
.Tonight... Breezy. Mostly cloudy. Showers or thunderstorms possible. Low 50 to 55. Wind east to northeast at 10 to 20 mph with gusts to 25 mph.
.Thursday... Breezy. Considerable cloudiness. High 58 to 63. Wind east to northeast at 10 to 20 mph with gusts to 25 mph.
Normal temperatures for Thursday
Sunrise Thursday: 6:56 AM CDT
Sunset Thursday: 7:05 PM CDT