


Area Forecast Discussion
Issued by NWS Marquette, MI
Issued by NWS Marquette, MI
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656 FXUS63 KMQT 171145 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 745 AM EDT Fri Oct 17 2025 .KEY MESSAGES... - Expect unseasonably warm temperatures and breezy conditions today. A rogue gust or two up to 35 knots/40 mph cannot be ruled out between Munising and Grand Marais late this afternoon. - After a break this morning, a cold front brings rain chances back from west to east this afternoon through this evening. The greatest rain chances are in the eastern U.P. this evening. - Several days of lake enhanced/effect rain showers are expected from Monday night through the middle of next week. Expect breezy conditions on Tuesday. && .DISCUSSION... Issued at 307 AM EDT Fri Oct 17 2025 A warm front moving through and out of the U.P. this morning brings rain showers over the north, central and east before ending over the aforementioned areas around 8 AM EDT. While most spots have seen only light rainfall amounts (around 1 to 3 tenths of an inch), with more vigorous showers over the south central dropping a little heavier rainfall over there over the past few hours, we do have some spots in the south central approaching 1 inch. As this band of showers continues into the rest of the central and east this morning during the pre-dawn hours, we could see an additional half inch or so across these areas before the rain showers cease over the U.P. this morning. With the warm front out of area by late this morning, expect generally dry but warm and moist conditions as we become unseasonably warm today, with highs getting into the mid 60s in the east to lower 70s in the west. With a southwesterly LLJ at around 40 kts at 850mb today and some breaks in the cloud cover, we could see some gusty southwesterly winds at the sfc today up to 30 mph, especially over the downslopes in the east where a rogue gust or two up to 40 mph isn`t out of the question this afternoon (thinking from Munising to Grand Marais a.k.a. around the Pictured Rocks area). As the cold front starts to move into the western U.P. early this afternoon, we could begin to see showers and potentially a non- severe thunderstorm or two develop just ahead of and along the frontal boundary (20 to 40% chance). As the front continues to push eastward with time the rest of this afternoon into this evening, the synoptic forcing will improve. Thus, expect the rain chances to improve the further east one is across the Upper Peninsula later this afternoon into tonight, with the central U.P. having around a 30 to 50% chance of measurable rainfall and the east a 50 to 80% chance. While generally only light rainfall of around a few hundreths to a couple tenths of an inch are expected across most of the U.P. with the cold front`s passage this afternoon and evening, a few spots could see up to a half inch or more of liquid in the heavier showers and storms. As the cold front passes through tonight, expect the winds to die down from west to east behind it. Even behind the cold front, expect temperatures to be fairly mild and above normal still on Saturday as partly cloudy skies allow high temperatures to reach into the 60s to even potentially 70 across Upper Michigan. However, a secondary cold front looks to bring more normalized temperatures back across the region Saturday night. While we may see some showers and a storm or two over the far east during the day Saturday, we could see rain chances spread a little bit back to the east Saturday night into Sunday as the cold air advection associated with the secondary cold front wraps into a shortwave low lifting along the frontal boundary from the Mid-Mississippi Valley Saturday night to Lower Michigan Sunday morning. This may set us up for some lake enhanced rain showers over our area, mainly the east (30 to 60% chance, highest over the east). As the shortwave passes the U.P. to the east on Sunday, expect highs in the lower to mid 50s; the rain showers look to end over the east Sunday evening as high pressure ridging quickly moves over the area. Expect the dry conditions Sunday night into Monday morning to not last all that long as a troughing pattern over the Plains quickly moves towards the Upper Midwest, eventually coalescing into a robust low pressure over the Upper Great Lakes by Tuesday morning. As this occurs, expect rain showers to return to the area Monday night and to continue through the mid-week as cold air advection and shortwaves rotating around and into the low bring lake enhanced to lake effect rain showers across the region. In addition, with the robust cold air advection bringing 850mb temperatures of around -4C to the region, we could see strong northwesterly gusts up to 30 to 40 mph across the U.P. Tuesday, with the highest gusts expected in the Keweenaw. The rain chances look to remain until late next week when the troughing finally leaves and is replaced by ridging. && .AVIATION /12Z TAFS THROUGH 12Z SATURDAY/... Issued at 744 AM EDT Fri Oct 17 2025 Radar shows main warm frontal precip band shifting to the eastern UP as of 12z Fri, with showers becoming isolated in coverage over the western half. Flight categories have mostly improved to VFR across the west, with a mix of VFR/MVFR in the east and some intermittent IFR cigs around SAW. Expect an improving trend through this morning as rain continues to push off to the east. Winds will remain breezy out of the south-southwest around 10 kt gusting to 20 kt at most sites through much of the period, but LLWS concerns will ease through 16z Fri as profiles become more unidirectional with height and winds aloft start to diminish. Mainly VFR for the rest of the period. Showers redeveloping from west to east this evening as a cold front pushes through the region after 00z. Could see a few embedded thunderstorms with this feature, but probability is too low for inclusion in the TAFs. && .MARINE... Issued at 351 AM EDT Fri Oct 17 2025 Southerly winds to 20 to 25 knots over the open eastern lake and 20 to potentially even up to 30 knots along the southerly downslopes early this morning increase to 20 to 30 knots with a few gale force gusts up to 35 knots possible (10 to 30% chance) over the eastern lake by late this afternoon as a cold front moves in from the west this afternoon through tonight. Immediately behind the front, we could see a few southwesterly gusts up to 30 knots before winds die down to around 20 knots or less late tonight across the lake. Expect the generally light winds to remain across the lake until a shortwave low rides up the cold frontal boundary from the Mid- Mississippi Valley through Lower Michigan into Canada Saturday night through Sunday; when this happens, expect winds to pick up from the northwest and north-northwest to 20 to 30 knots late Saturday night to Sunday across Lake Superior; there is even up to a 30% chance for gales up to 35 knots over the eastern lake on Sunday. While winds subside Sunday night into Monday morning as high pressure ridging moves through the region, expect them to pick up once again Monday into Tuesday as a troughing pattern over the Plains coalesces into a 29.4 inch low over the Upper Great Lakes by Tuesday morning. This in turn could bring south to southeasterly winds of 20 to 30 knots over the lake on Monday before cold air advection from Canada drops into the region and brings northwest winds of 30 to gales of potentially 40+ knots across Lake Superior by Tuesday (up to around a 40 to 50% chance for gales of 35 knots or greater Tuesday according to the NBM). && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ DISCUSSION...TAP AVIATION...CB MARINE...TAP