/Issued 5:12 PM CDT, Monday, August 8, 2016/
Southern portions of the Northland from the Brainerd Lakes toward Hinckley/Pine City, east to the Hayward Lakes in northwest Wisconsin have the greatest chance for possible heavy rain and maybe some flooding during the Wednesday-Thursday time frame. Showers and thunderstorms are still expected to affect northern Minnesota into far northern Wisconsin during the aforementioned time frame as well, but at this time given the setup it appears that the greatest chance for repeated rounds of storms will be more in western, central and eastern Minnesota vs. northern Minnesota.
Severe weather outlook for Tuesday, August 9, 2016. Source, Storm Prediction Center.
Severe weather outlook for Wednesday, August 10, 2016. Source, Storm Prediction Center.
Forecast for Duluth and Superior
Normal temperatures for Tuesday
Sunrise Tuesday: 5:59 AM CDT
Sunset Tuesday: 8:28 PM CDT
Tonight's low temperature forecast. Source, National Weather Service Duluth, Minnesota.
Tuesday's high temperature forecast. Source, National Weather Service Duluth, Minnesota.
Weather Summary for NE Minnesota and NW Wisconsin
Date: August 8, 2016
Near perfect summer weather continued today with high temperatures in the mid 70s to around 80 degrees with slightly cooler temperatures close to Lake Superior. Dew points were in the mid 50s to low 60s and winds were out of the south or east at 10 to 15 mph. Sky conditions ranged from partly to mostly cloudy across the area today with low level cumulus clouds moving up from the south while high level clouds drift across the Northland from west to east. Surface map late this afternoon had high pressure of 1018-1020mb over the Great Lakes with low pressure of 1004mb over southeast Saskatchewan Province, a cold front attached to this low was over the western Dakotas.
Forecast Discussion for NE Minnesota and NW Wisconsin
Tonight (August 8)
Partly to mostly cloudy skies with a chance for a few showers and possibly a thunderstorm in northern Minnesota later in the night as a cold front moves east into northwestern Minnesota. Low temperatures will be in the 50s and 60s with a south or southeast wind at 10 to 15 mph.
Tuesday (August 9)
Warm and humid with a few showers and thunderstorms possible especially during the afternoon-evening hours.
A cold front will move slowly toward the south/east and through the Northland on Tuesday. Low pressure will track from southern Ontario to Hudson Bay with an area of high pressure building into Manitoba and western Ontario Provinces by Tuesday night.
The atmosphere could become rather unstable on Tuesday with CAPE values nearing 2000 j/kg. 30-40 knots of bulk shear and 0-6 km shear is forecast to be over the Northland along with westerly mid level winds at around 30-50 knots with a southwest or west-southwest low level jet generally around 20-30 knots along and just ahead of the cold front.
Convergence near this cold front won't be the best, and most of the forcing will remain north of the border, but a few spotty thunderstorms can't be ruled out Tuesday afternoon or evening in parts of the Northland, and if storms are able to develop they could become strong to severe with a threat of gusty winds and hail.
Highs on Tuesday will mainly be in the 80s with lows in the 50s and 60s. Dew points are expected to climb into the 60s to lower 70s so it will feel muggy tomorrow.
Winds tomorrow will be out of the southwest or west at 10 to 20 mph with north, east or south winds tomorrow night at 5 to 15 mph.
Wednesday and Thursday (August 10-11)
The setup for mid week will feature a frontal boundary to our south with low pressure tracking east or northeast out of South Dakota with high pressure off to the north. Abundant moisture and warm air advection will lift up and over that boundary, and this combined with a couple of disturbances moving out of the northern Plains should cause a couple rounds of showers and thunderstorms over the northern Plains and Upper Midwest -- With the deep tropical airmass in place the potential is there for locally heavy rainfall in parts of the Northland for Wednesday and Thursday, although the exact location of where the axis of highest rainfall totals setup is uncertain at the moment as it could be more in central or even southern Minnesota instead of northern Minnesota.
A few strong to severe thunderstorms are also possible especially across western-southern parts of the Northland for Wednesday and Thursday with hail and strong winds being the primary hazards.
High temperatures should mainly be in the 70s for Wednesday and Thursday but 80s are possible if skies clear out for a bit, it will be cooler around Lake Superior with a stronger onshore wind developing during the middle of the week.