/Issued 4:35 PM CDT, Thursday, July 25, 2013/
-This weekend’s weather will be dominated by an unusually strong upper level trough and area of low pressure which will move very slowly toward the east. This 1st map is valid for 1 PM Friday.
-This next map is for 1 PM Saturday.
-And finally for 1 PM Sunday.
Note: All 3 maps are from the 18z NAM/WRF model from 7.25.13 and these maps represent the 500mb forecast. The upper low starts in NE Minnesota Friday Afternoon and doesn’t exit to our east until Sunday PM when it’s forecast to reach Eastern Lake Superior/Eastern Upper Michigan vicinity.
Today’s Weather Summary for Northeast Minnesota and Northwest Wisconsin
One last mild day before the chill hits. Two cold fronts were draped over the Upper Midwest and Western Great Lakes Today. Front number one was down in Southern Minnesota into Northern Wisconsin. Front number two was over Northern Minnesota. The Northland saw a mix of clouds and sun Today with scattered showers and thunderstorms sprouting up due to the cold front over the area along with a potent disturbance/upper low-trough which is digging south out of Southern Manitoba and Western Ontario. A few of the thunderstorms during the Afternoon did become severe with reports of hail and high winds. The atmosphere is unstable enough to support stronger convection Today with late Afternoon CAPE averaging 1000 j/kg along with lifted indices of -2 to -4C. 0-6 KM Bulk Shear and Effective Bulk shear is running in the 40 knot range Today which is favorable for stronger storms. Winds aloft are also strong which is helping as well. High temperatures Today were in the 70s and 80s with winds all over the place, but generally out of the west or north at 5 to 15 mph.
Today’s water vapor satellite imagery. Note the darkening over NW Minnesota, this is part of an upper level disturbance which has helped to spawn the scattered strong-severe t’storms that occurred over portions of the Northland Today.
Forecast Discussion for Northeast Minnesota and Northwest Wisconsin
Short Term Forecast – Confidence: High.
Tonight (July 25th)
The main concern will continue to be the scattered thunderstorms which will continue to affect parts of the Northland before Midnight. This activity will continue to track east or southeast as a cold front drops south out of Northern Minnesota. Isolated severe thunderstorms are possible with hail and strong winds being the primary hazards along with heavy rainfall and dangerous lightning. Be sure to stay weather aware during the Evening hours. Remember if you can hear thunder you’re close enough to be struck by lightning. When thunder roars get indoors.
Partly to mostly cloudy skies are expected Tonight with some lingering showers possible after Midnight. Lows will be in the 40s and 50s with winds becoming north at 10 to 20 mph.
Friday and Friday Night (July 26th)
A very cool airmass settles into the region during this period as an upper low/trough sets up just east of the Northland. 850mb temperatures are forecast to fall to +2 to +6C which is really cold for the time of year. Expect partly sunny to mostly cloudy skies on Friday with some showers possible at times. Friday Night will feature partly to mostly cloudy skies with a continued chance for some showers. Highs Tomorrow will only be in the 50s and 60s with lows Tomorrow Night in the 40s to around 50 degrees. North, northeast, or northwest winds are expected this period at 10 to 25 mph.
Extended Forecast – Confidence: High.
Saturday through Monday (July 27th-29th)
A cool Saturday with clouds and the possibility for a few showers as a strong upper level low and trough sits and spins across the Upper Great Lakes. Highs will be in the 50s and 60s with lows mainly in the 40s. Should see some improvements for Sunday and Monday as the upper level system begins to move farther toward the east. Highs on Sunday will be in the 50s and 60s with lows in the 40s. Monday’s high temperatures will reach the 60s and 70s.
Long Range Forecast – Confidence: High.
(July 30th-August 4th)
A few showers are possible during the early/middle part of next week (30th-31st) this activity would be caused by a cold front which is forecast to pass through the Upper Midwest during that aforementioned time period. Otherwise things are looking kinda dry during the remainder of this period. Near to below average temperatures are forecast from 30 July thru 4 August.
5 DAY FORECAST FOR DULUTH/SUPERIOR
.Tonight… Scattered showers and thunderstorms before Midnight. Partly to mostly cloudy. Low 50 to 55. Wind becoming north to northeast at 10 to 20 mph.
.Friday… Much cooler. Considerable cloudiness with a few showers possible at times. High 56 to 61. Wind north to northeast at 10 to 20 mph.
.Friday Night… Considerable cloudiness. A few showers possible, mainly during the Evening. Low 42 to 47. Wind north at 10 to 20 mph.
.Saturday… Cool for the time of year. Considerable cloudiness with a few showers possible at times. High 61 to 66.
.Saturday Night… Becoming mostly clear. Low 42 to 47.
.Sunday… Partly sunny. High 65 to 70.
.Sunday Night… Partly cloudy. Low 45 to 50.
.Monday… Partly cloudy. High 70 to 75.
Normal temperatures for Tomorrow
Sunrise Friday: 5:42 AM CDT
Sunset Friday: 8:48 PM CDT