/Issued 6:28 PM CDT, Saturday, August 4, 2018/
18z NAM 8.4.2018
The last of the steady rain is exiting far northeast Minnesota early this evening while a few showers and thunderstorms move east across far northern Minnesota as of 6:50 PM.
Goes-16 visible satellite loop for Saturday, August 4, 2018 (Loop time 12:57 PM to 5:52 PM)
Overcast skies continued late this afternoon in northeast Minnesota and northwest Wisconsin but there is some clearing moving east out of central Minnesota, also note the thunderstorms which are impacting extreme northern Minnesota and southern Ontario Province.
18z HRRR model
Simulated Radar forecast valid 1 AM Sunday morning to 7 PM Sunday evening. Widely scattered showers and thunderstorms continue at times into Sunday morning, then the focus for additional storms could shift mostly to northwest Wisconsin for Sunday afternoon.
24-hour Rainfall Reports
Note: Rainfall totals listed below from 5 PM Friday to 5 PM Saturday, August 3-4, 2018
Moose Lake, MN: 1.95 in
Clam Lake, WI: 1.58 in
Glidden, WI: 1.44 in
Two Harbors, MN: 1.39 in
Duluth, MN: 1.21 in
Saginaw, MN: 1.19 in
Hayward, WI: 1.08 in
Minong, WI: 0.90 in
Hinckley, MN: 0.81 in
McGregor, MN: 0.77 in
Brainerd, MN: 0.64 in
Solon Springs, WI: 0.55 in
Ashland, WI: 0.53 in
Ely, MN: 0.50 in
Washburn, WI: 0.46 in
Siren, WI: 0.44 in
Superior, WI: 0.36 in
Hill City, MN: 0.32 in
Eveleth-Virginia, MN: 0.32 in
Chisholm-Hibbing Airport: 0.29 in
Isabella, MN: 0.29 in
Grand Marais, MN: 0.06 in
Note: 1.21 inches of rain so far today at the Duluth Airport, this is the 2nd greatest rainfall total on record for August 4. Record wettest August 4 occurred in 1988 with 1.35 inches of rain.
A wet day in parts of northeast Minnesota and northwest Wisconsin as widespread light to moderate rain fell most of the day, the rain plus extensive clouds kept temperatures on the cool side with highs today in the lower 60s to lower 70s.
It was warmer farther west where there was some sun at times today with less rain, as a result, highs climbed into the mid 70s to low 80s from International Falls to Grand Rapids to the Brainerd lakes area.
Surface map late this afternoon had 2 cold fronts, one was over the northwest half of Minnesota, the other was over the central Dakotas.
The atmosphere has become quite unstable this afternoon in north central Minnesota with meso-analysis showing CAPE up to 2000 J/kg along with mid level lapse rates ~7.0 c/km. There have been a few showers and thunderstorms that have popped up this afternoon in this more unstable environment in far northern Minnesota, but so far none of the storms have been too strong with limited wind shear in place today.
It will remain muggy through Sunday with dew points holding in the lower 60s to lower 70s, the highest values found in eastern Minnesota and northwest Wisconsin. Lows tonight will be in the upper 50s to middle 60s under mostly cloudy skies with patchy fog.
Highs Sunday are forecast to be in the 80s, and this combined with the higher dew point temperatures will make it feel a little toasty!
Will have a couple cold fronts move through the Northland through Monday. The greatest instability will be over our area tonight and Sunday, and this is when we could see a few showers and thunderstorms develop. Not much instability over our area on Monday with less humid conditions as well, so probably won’t get much if any shower/thunderstorm development to take place with Monday’s cold frontal passage.
Note: There is still a risk for a few strong to severe thunderstorms through Sunday evening. This risk appears to peak Sunday afternoon-early evening, and mainly in northwest Wisconsin and far eastern Minnesota where the best overlap of moisture, instability and wind shear is forecast to be. Not much shear in our area tonight with rather meager winds aloft, so although a strong storm could occur, the overall risk of severe weather is fairly low. But things will change on Sunday with mid level winds increasing to 30-50 knots while upper level winds increase to >100 knots across the Northland, this will help increase the amount of wind shear with models showing 30 to 45 knots of shear over eastern Minnesota and northern Wisconsin on Sunday, and its this area that has the greatest potential for seeing a few severe thunderstorms Sunday afternoon or Sunday evening with damaging winds, large hail and even an isolated tornado risk. Can’t completely rule out an isolated stronger storm in northeast Minnesota on Sunday, but I think the better risk for severe weather if any does develop would be a little farther to the south.
Duluth, Minnesota Climate Normals for August 5
Sunrise Sunday: 5:54 AM CDT
Sunset Sunday: 8:35 PM CDT