/Issued 2:38 PM CDT, Friday, July 12, 2013/
-There is a slight chance that rainfall exceeds flash flood guidance Tonight through 7 PM Saturday in Western and Northcentral Minnesota (green outline area) Source, Weather Prediction Center.
Today’s Weather Summary for Northeast Minnesota and Northwest Wisconsin
A warm and more humid day in the Northland as south winds ramp up out ahead of a cold front which as of 2 PM stretched from extreme Northwest Minnesota to Central South Dakota. High temperatures were in the 80s with 70s along the North Shore of Lake Superior. Dew points were generally in the 60s Today and winds were out of the south at 10 to 20 mph with a few higher gusts. Sky conditions ranged from sunny to partly sunny with a few showers earlier in the day in far Northern Minnesota otherwise it was dry.
Forecast Discussion for Northeast Minnesota and Northwest Wisconsin
Short Term Forecast – Confidence: High.
Tonight (July 12th)
Looks kinda stormy Tonight especially west/northwest of the Twin Ports. A cold front looks like it’ll remain more or less in Northwestern Minnesota with plenty of moist/unstable air along and ahead of this boundary. Dew points in the 60s. PWS of 1.00″-2.00″. CAPE of 1000-2000 j/kg. Lifted Indices of -2 to -6C. These ingredients combined with enough lift provided by the cold front should help trigger scattered showers and thunderstorms Tonight.
It may take a while for things to form, however, thanks to a layer of warm air aloft. Late Afternoon 700mb temperatures were in the +10 to +12C range across Northern Minnesota, so these temperatures will have to lower just a bit before convection can begin to develop. Once storms do form they will have 30-45 knots of deep layer shear to work with, plus a nice 30-50 knot low level jet, so a few severe thunderstorms are possible Tonight, mainly along and west of a line from Brainerd to Grand Rapids to Hibbing to Crane Lake. Hail and high winds will be the main hazards along with torrential rain due to the abundant moisture in place.
How far east these storms get remains uncertain as capping and a decrease in instability will be found from Northeast Minnesota into Northwest Wisconsin Tonight, but if showers and thunderstorms were to affect these areas they should hold off until Midnight or later. Lows Tonight will be in the 60s to around 70 degrees with south winds at 10 to 20 mph.
Saturday and Saturday Night (July 13th)
A frontal boundary should stall out west/north of our area. A very moist and somewhat unstable airmass will cover the area during this period with the highest CAPE across the Western/Northwest parts of the Northland. Scattered showers and thunderstorms are expected to occur Tomorrow and Tomorrow Night with heavy rain possible where-ever thunderstorms occur. It still looks like Northcentral Minnesota has the best chance for seeing more significant convection this period with lesser chances once you get to Northwest Wisconsin. There’s also a risk for a few severe thunderstorms in Northern Minnesota with hail and high winds being the main hazards. Highs Tomorrow will be in the 70s and 80s with lows Tomorrow Night mainly in the 60s. Winds will be out of the south or east at 10 to 20 mph.
Extended Forecast – Confidence: High.
Sunday through Tuesday (July 14th-16th)
Weather pattern remains virtually the same with a frontal boundary draped over the Northern Plains and Upper Midwest with moisture and instability near this front causing scattered showers and thunderstorms at times. It does appear that Sunday and possibly Monday has the greatest chance for some rain in parts of the Northland, then on Tuesday most of the area may stay dry. High temperatures will be in the 70s and 80s on Sunday and mainly the 80s Monday and Tuesday. Lows Sunday Night and Monday Night will be in the 50s and 60s.
-12z NAM/WRF rainfall forecast through 7 PM Monday. Yellow, orange, and red colors indicate the potential for 1-3″+ of rain through Monday.
-12z GFS rainfall forecast through 7 PM Monday. Both forecast models indicate the heaviest rain totals remaining in Western/Northern Minnesota. Will see what happens.
Long Range Forecast – Confidence: High.
A few showers or thunderstorms are possible at times between Wednesday-Friday (17th-19th) Dry from the 20th-22nd the way it looks now. Near to above average temperatures are forecast through this period.
5 DAY FORECAST FOR DULUTH/SUPERIOR
.Tonight… Partly to mostly cloudy. A few showers or isolated thunderstorms possible, mainly after Midnight. Low 63 to 68. Wind south at 10 to 20 mph.
.Saturday… Showers or thunderstorms possible at times. High 77 to 82 but it may be cooler closer to Lake Superior. Wind south at 5 to 15 mph.
.Saturday Night… A few showers or thunderstorms possible. Low 60 to 65. Wind south to southeast at 5 to 15 mph.
.Sunday… Partly to mostly cloudy. High 80 to 85.
.Sunday Night… Partly cloudy. Low 60 to 65.
.Monday… Partly sunny. High 75 to 80.
.Monday Night… Partly cloudy. Low 60 to 65.
.Tuesday… Partly cloudy. High 82 to 87.
Normal temperatures for Today
Sunrise Saturday: 5:28 AM CDT
Sunset Saturday: 9:00 PM CDT