


Area Forecast Discussion
Issued by NWS Marquette, MI
Issued by NWS Marquette, MI
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753 FXUS63 KMQT 091853 AFDMQT Area Forecast Discussion National Weather Service Marquette MI 253 PM EDT Thu Oct 9 2025 .KEY MESSAGES... - Widespread light to moderate rain expected tonight and Friday. - Gale force gusts to 35-40kts are becoming more likely Friday afternoon and evening over Superior (40-80% chance). && .DISCUSSION... Issued at 252 PM EDT Thu Oct 9 2025 Afternoon RAP analysis has the midlevel ridge axis shifting over the Great Lakes this afternoon, with the surface high currently centered over southern Ontario. Resulting southerly flow is bringing in slightly warmer temperatures than in the past couple of days, with most of the area sitting in the mid and upper 50s and expected to peak near to just above 60F while skies remain sunny. Meanwhile, a shortwave is currently dropping into Manitoba, with an associated cold front extending southward into the Dakotas. The compact shortwave continues moving into Ontario tonight with the cold front tracking eastward towards the Great Lakes. Ahead of the front, south to southwest winds will be on the increase; gusts up to 20-25mph will become more common overnight, but stronger gusts in excess of 30mph will be possible in the southerly downsloping areas nearer the Lake Superior. Winds over the water and across the Keweenaw turn even stronger immediately ahead of and behind the front with rapid height rises in its wake. Gale-force gusts will be possible across the lake, while winds gust in excess of 30mph over the Keweenaw. Winds quickly decrease Friday evening while shifting over to the NW. Rain is also expected to press into Upper Michigan from west to east tonight, becoming more widespread Friday morning as a surface low develops along the cold front. Guidance continues to favor development of the low around/just NW of Thunder Bay Friday morning , slowly tracking southeast through the Great Lakes through early Saturday. In terms of sensible weather, this means a dry slot may support a break in rainfall early Friday for the west half before a secondary push of rain wrapping around the low moves into the forecast area in the afternoon and evening. Rain finally tapers off Friday night. Most of the UP is looking to pick up a wetting rainfall with widespread totals of a tenth to quarter inch by Friday evening. However, NBM shows a low (25%) chance for higher rain totals in excess of a half an inch, mainly across the northern half of the UP. Perhaps this is due to some lake enhancement with the second window of wraparound rain showers Friday afternoon/evening? Will also note that while thunder is not looking very likely given very limited buoyancy, will not rule out a rumble or two tonight through Friday. After rain wraps up Friday night, expect dry weather into the weekend as a ridge builds over the area once more. A slight warming trend is noted between the two days thanks to the next system moving closer to the region Sunday. Daytime highs Saturday look to peak near 60F and then widespread mid 60s Sunday. Broad troughing begins to establish itself across the Northern Rockies and the initial wave lifting northeast from the base results in a surface low lifting from the Dakotas into Manitoba Sunday. A warm front associated with this system presses into the Upper Great Lakes Sunday night followed by its cold front Monday. Rain looks to move into the region thanks to these features Sunday evening then gradually taper through the day Monday. This will also lead to another period of gusty winds Sunday into Monday courtesy of a tight pressure gradient. Another high looks to build across the region afterwards through the middle of next week before the next low lifts out of the Central Plains. Temperatures run cooler after Monday with highs in the 50s and lows in the 30s and 40s. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 206 PM EDT Thu Oct 9 2025 VFR conditions continue through this evening, but rain showers overspread the UP ahead of a low pressure approaching from the northwest. While most showers during this period will be above MVFR vis, a few at the onset look to lower vis to MVFR briefly at IWD/CMX. After this round progresses across the sites by late morning, periods of showers and low cigs are expected to continue as the low pressure crosses over eastern Lake Superior and far eastern Upper Michigan. Mainly MVFR cigs at CMX/SAW, but possibly IFR by late in the day Friday. Otherwise southerly winds will remain light 8-12 kts into this evening, becoming gusty to 20-25 kts tonight ahead of the cold front. Also, a brief period of LLWS is expected at IWD tonight. Gusty northwest winds are expected on Friday behind the cold front. && .MARINE... Issued at 252 PM EDT Thu Oct 9 2025 Southerly winds will be on the increase this evening into tonight ahead of a cold front (currently over the Dakotas). By Friday morning, a surface low will develop along the cold front, with winds further increasing to around 30kts across much of the lake ahead of and immediately behind the system. Gale potential still exists, with the latest Euro ensembles coming in with the highest chances for gales (around 50-80% chance), though this remains an outlier among probabilistic guidance. Still, with strong winds aloft, and warm lake temperatures suggesting a good potential for mixing, have chosen to go slightly above guidance and add in some 35-40kt SW to NW gales over central and eastern Lake Superior for the daytime hours Friday. Gales quickly fall off Friday evening, and winds continue to gradually decrease the rest of the night while slowly veering to the northeast. Expecting winds below 20kts Saturday. Increasing pressure gradient is expected late Saturday night into Sunday as the next system organizes in the Northern Plains. An upward tick has been observed in guidance, now suggesting that a low end southeasterly/southerly gale looks good with this system late Sunday/Monday. Winds become northwesterlies behind the system`s cold front Monday night/Tuesday and slowly fall below 20kts by Tuesday night. && .MQT WATCHES/WARNINGS/ADVISORIES... Upper Michigan... None. Lake Superior... None. Lake Michigan... None. && $$ DISCUSSION...LC AVIATION...77 MARINE...LC