Shower coverage is expected to increase across the Northland this evening and overnight, with more rain and showers continuing at times on Thursday. There likely will be some brief heavier downpours embedded in this rain, and there could even be an isolated thunderstorm or two tonight and Thursday given an increase in instability, but widespread thunderstorms and severe weather is not expected in our area through Thursday. Note: Rainfall totals of around a half inch to an inch are possible in much of northeast Minnesota and northwest Wisconsin through late Friday afternoon, but the best chance for getting a more widespread rain comes late tonight and during the day Thursday. Friday may end up being dry, or a setup where we just see a few isolated showers or storms in our area.
Here’s the NAM 3km model simulated radar forecast valid thru 7 AM Friday.
Radar image from late Wednesday afternoon showing two areas of more organized showers and thunderstorms, one over eastern North Dakota and northwest Minnesota, the other across the southern half of Minnesota – Both areas of rain are lifting to the north/northeast.
The type of pattern that is in place often results in wet and stormy weather for the upper Midwest with a strong ridge to the southeast and a trough over the west, this leads to a SW mid/upper level flow in our area and a lot of moisture flowing north out of the Gulf and into the upper Midwest. Note: The only other thing we need in order to get some rain and storms to develop in our area is some kind of lifting mechanism in the form of a frontal boundary or disturbance, and will see an occasional disturbance break off the western trough and work its way through the upper Midwest tonight and Thursday, and then will finally see a cold frontal passage take place late Saturday and again early next week.
A rich supply of moisture in place with a flow coming straight north out of the Gulf of Mexico today, and a similar pattern should stick around through Saturday.
Areas of fog and haze will continue especially near Lake Superior tonight and Thursday with dense fog possible at times due to a humid air mass over the area.
A dense fog advisory is in effect for western Lake Superior thru Thursday morning, and we could see this advisory extended beyond Thursday morning.
Temps will remain on the mild side through Saturday with highs on Thursday in the 60s and 70s, warming to the 70s and 80s Friday and Saturday. Note: Much cooler temperatures (ranging from around 45 to 60 degrees) will be found closer to Lake Superior due to a lake breeze over the next few days.
With a muggy air mass over the area combined with the warm temps, it certainly will feel more like July than mid May around here over the next few days.
A look at the high temperature forecast for Thursday through Saturday.
Not a whole lot of rain so far in the Northland with mostly trace to around a tenth of an inch of rain since Tuesday evening across northwest Wisconsin and far eastern Minnesota, while northern Minnesota has been mostly dry today.
…24-Hour Rainfall Totals from 7 AM Tuesday to 7 AM Wednesday, May 18-19, 2021…
- Glidden, WI: 0.25″
- Grand Marais, MN: 0.16″
- Clam Lake, WI: 0.16″
- Hayward, WI: 0.13″
- Barnes, WI: 0.12″
- Washburn, WI: 0.09″
- Siren, WI: 0.06″
- Hinckley, MN: 0.05″
- Moose Lake, MN: 0.03″
- Ashland, WI: 0.02″
- Two Harbors, MN: 0.01″
- Duluth Airport: 0.01″
- Brainerd, MN: 0.01″
- Chisholm-Hibbing Airport: 0.01″
The Euro ensemble and GEFS models are in good agreement in terms of rainfall amounts thru May 31st.
Rainfall amounts of around 2 inches are possible in northeast Minnesota and northwest Wisconsin over about the next two weeks. Will see what happens.