


Area Forecast Discussion
Issued by NWS Marquette, MI
Issued by NWS Marquette, MI
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887 FXUS63 KMQT 071758 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 158 PM EDT Tue Oct 7 2025 .KEY MESSAGES... - A widespread freeze/frost is possible for inland areas tonight. A freeze warning and frost advisory have been issued. - Frost and/or freeze conditions will be possible again Wednesday night. && .DISCUSSION... Issued at 314 AM EDT Tue Oct 7 2025 A weak surface trough is noted over western Lake Superior underneath the leading edge of a broad trough that extends across much of central Canada. A 300mb jet streak ahead of the two supported widespread lift last evening, which resulted in scattered light radar returns overhead. The dry, near surface airmass though prevented much, if any rain, from reaching the ground. Temperatures so far have fallen into the 40s for most, with a couple of high 30s being observed as well. With clear skies noted on GOES IR imagery, additional cooling is expected, with potential for widespread mid to upper 30s by sunrise across the interior west/central. A weak cold front upstream in the Northern Plains will move eastward through Lake Superior today and the resultant increasing pressure gradient and post frontal cold air advection will enable gusty winds to develop across the region. Strongest winds near 35 mph will be this morning in the Keweenaw from the west, which will shift northwesterly by afternoon. Elsewhere, 20 mph gusts should be expected, with upwards of 30 near the Lake Superior lakeshore east of Marquette. Temperatures look to peak in the mid to upper 50s for most, save low 60s south-central. The airmass will continue to dry through the day as high pressure presses eastward into the area and subsidence increases. With PWATS falling to near 0.2 inches by tonight, light winds developing, and 850mb temps falling to -3 to - 1C, freeze conditions look good tonight for interior areas of central and western Upper Michigan. NBM probabilities suggest 60-85% chance for these areas to fall to at least 32 degrees and 20 to 35% chance of falling below 28F. With this in mind and the classic signals for effective radiational cooling, opted to upgrade the inherited freeze watch to a freeze warning for areas removed from the lakeshores of central and western Upper Michigan. For the Keweenaw and east, went with a frost advisory given the slightly warmer anticipated temperatures. Dry conditions prevail Wednesday and Thursday as mid-level ridging extends northward from middle CONUS into Canada and surface high transits Upper Michigan. A slight warming trend is noted between the days, with Wednesday in the mid to upper 50s climbing into the 60s for many areas Thursday. Frost/freeze conditions look possible again Wednesday night, with the risk area now stretching into eastern Upper Michigan. Ridge axis shifts through the Upper Great Lakes Thursday afternoon with a sharp closed low/shortwave dropping southeast from Manitoba into Ontario early Friday. An associated cold front will be pulled through the region Friday, with chances for precip ahead of the boundary late Thursday night into Friday morning. Another surface high and mid-level ridge move in afterwards, which favors dry conditions until Sunday. && .AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/... Issued at 156 PM EDT Tue Oct 7 2025 VFR conditions prevail during the 18Z TAF period. Northwest winds remain elevated this afternoon between 10-15 kts in the wake of the cold front now progressing over the eastern UP. Gusts are expected up to 30 kts at CMX and around 20 kts at SAW until sunset when winds shift more northerly and diminish. At that point, a colder airmass passes overhead and lake effect cloud cover returns. Best coverage will be at SAW where a few sprinkles could be seen and periods of high-end MVFR cigs can`t be ruled out (15-25% chance). CMX may see broken skies at times, but confidence was too low to include, especially given VFR cigs should persist. Mostly clear skies are expected at IWD. Skies scatter out Wednesday morning as high pressure centers overhead. && .MARINE... Issued at 314 AM EDT Tue Oct 7 2025 West winds will strengthen to 25 kts ahead of an approaching cold front early this morning. The cold front will push through the area by mid-late morning with winds becoming northwest to 30 knots behind the front. A few gusts to gale are possible at the higher platforms. Winds become light on Tuesday night, below 20 kts as high pressure settles into the region. Low pressure tracking through Ontario will bring increasing southerly winds for Thursday into Friday, possibly up to 30 kts. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... Frost Advisory from midnight tonight to 10 AM EDT Wednesday for MIZ001-003-006-007-014-085. Freeze Warning from midnight EDT /11 PM CDT/ tonight to 10 AM EDT /9 AM CDT/ Wednesday for MIZ002-004-005-009>013-084. Lake Superior... None. Lake Michigan... None. && $$ DISCUSSION...JTP AVIATION...77 MARINE...JTP