


Area Forecast Discussion
Issued by NWS Marquette, MI
Issued by NWS Marquette, MI
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474 FXUS63 KMQT 130752 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 352 AM EDT Mon Oct 13 2025 .KEY MESSAGES... - A round of showers presses west to east today. Rainfall accumulations are expected to remain light, generally less than 0.25". - Gusty southerly winds 20-30 mph veer northwest behind a passing cold front, diminishing in speed throughout the day. - Seasonable and dry weather follows into the midweek. && .DISCUSSION... Issued at 350 AM EDT Mon Oct 13 2025 Early morning RAP analysis and GOES satellite imagery reveal a ~110 kt 300mb jet extending from the Great Basin northeast across MN and into western Ontario. Underneath the nose of this jet streak, a ~988mb sfc low is meandering east across central Manitoba. Closer to home, the strong pressure gradient draped across the Upper Great Lakes is continuing gusty S flow, which has kept low temps in the 50s area wide. Ascent ahead of and along the system`s occluded/cold front is shoving a round of light rain across the west half of the UP as of writing this discussion. Through the reset of the day, the aforementioned frontal boundary presses eastward through the CWA, providing a wave a light to moderate showers as it does so. Guidance continues to highlight low QPF amounts, with the NBM favoring a 25-50% chance for >0.25" mainly confined to the Keweenaw. Elsewhere, expect lower amounts. Behind the frontal passage, clearing skies and breezy NW winds will prevail, providing wind gusts 20-25 mph to the Keweenaw and eastern Lake Superior shoreline communities. Given increasing CAA and clear skies, a chilly tonight is in store tonight where interior locations could dip into the 30s where successful radiational cooling occurs under a decoupling boundary layer. Heading into the midweek, a deepening trough over the US west coast forces downstream height rises and reintroduces sfc high pressure to the Great Lakes. This keeps quiet and seasonable weather in the forecast through at least Thursday. A few global models suggest an increase in PoPs Wednesday as a weak ridge riding shortwave skirts to our south, but opting to keep a dry forecast with antecedent dry airmass and subsidence overhead. PoPs return in the forecast late week and further into the weekend as western troughing continues east across the Rockies, breaking down the Midwest ridge. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 205 AM EDT Mon Oct 13 2025 Radar shows a band of rain showers associated with a cold front entering the far western UP as of 06z Mon, but observations from around the area show VFR conditions with cigs still mainly around FL100. Low level wind shear persists at the terminals thanks to a LLJ bringing south winds of 45-50 kt at FL020. LLWS will diminish at IWD and CMX by 08-09z and SAW by 10z as the front progresses eastward across the area through Monday morning, spreading showers into IWD and CMX through around 12z and SAW through ~14z. Expect mainly VFR conditions to persist at all sites, but could see a few brief bouts of MVFR through Mon morning in passing showers. Winds shift westerly behind the front by Monday afternoon, diminishing below 10 kt after ~22z Mon. && .MARINE... Issued at 350 AM EDT Mon Oct 13 2025 Gusty southerly winds 25-30 kts with a few isolated gales to 35 kts persist this morning as a tight pressure gradient is draped across Lake Superior ahead of a cold frontal boundary that is set to press west to east across the lake through this afternoon. As the front presses east, gusty S winds diminish below 30 kts while veering to the NW. For this reason, opting to let the ongoing Gale Warnings for the N and central lake expire at 12z (8 AM EDT). Winds settle to around 20 kts or less on Tuesday, save for some stray guts up to 25 kts over the southeastern waters, as high pressure builds in. Winds settle below 15 kts across the lake Tuesday night, holding through Thursday morning. High pressure quickly gives way on Thursday, reintroducing 20-30 kt winds to the lake for next weekend. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... Gale Warning until 8 AM EDT this morning for LSZ244-245- 264>266. Lake Michigan... None. && $$ DISCUSSION...BW AVIATION...CB MARINE...BW