textproduct: Marquette

KEY MESSAGES

- Scattered lake effect rain showers and gusty NW winds persist across the east half of the UP this evening, diminishing overnight.

- Longer period of lake effect snow showers and near normal temperatures Wednesday through early next weekend. Accumulating snow for the north wind snowbelts is becoming increasingly likely.

DISCUSSION

Issued at 302 PM EST Sun Nov 8 2026

Afternoon GOES water vapor imagery reveals a sharp shortwave trough digging across northern Ontario with the attendant surface low pressure reflection further north towards James Bay. A cold front has passed SE of the UP this morning, ushering in modest cold air advection and pressure rises that has contributed to gusty NW winds 25-45 mph, highest in the Keweenaw and over Lake Superior. Additionally, 850mb temps near 0 to -2C have supported blustery lake enhanced showers across the area, mainly the east half given the northwesterly fetch. Continued NW flow behind the departing will support these conditions for the remainder of the day before gradually tapering off tonight as a brief ridge and weak high pressure settle atop the region by Monday morning. Overnight temps fall into the 30s and 40s, warmest lakeshores. Another clipper, albeit more low amplitude, presses north of Lake Superior through Monday PM, bringing an uptick in SW winds and climbing temps into the upper 40s to low 50s, some 5-10 degrees above normal for this time of year. With the greatest forcing for ascent remaining north of the UP, thinking it should be a dry day, though can't rule out a light isolated shower in the east (<20%). Dry conditions hold through Tuesday as the clipper passes northeast of the Upper Great Lakes, veering breezy winds westerly and keeping one more day of above normal temps.

The more fun and challenging forecast presents itself during the latter half of this week as a closed upper low in the Canadian maritime provinces and far northern Quebec slowly retrogrades SW towards James Bay/western Quebec while several additional shortwaves round the far western base of the trough straight south across Ontario through the Great Lakes. In turn, this creates a somewhat prolonged period of northerly flow across Lake Superior, bringing down 850 mb temps between -7 to -11C Wednesday night through Saturday. Lake effect precipitation will begin to occur Wednesday afternoon as temps aloft cool to the 8-13C delta T before becoming all lake effect snow late into Thursday morning. LES persists across the north wind snowbelts through at least Saturday morning. Some appreciable snow accumulations may be on the horizon if necessary ingredients come together. Bufkit soundings in the N wind snowbelts suggest ample moisture in the lower levels but lack saturation within the DGZ, leading to lower SLRs and thus wetter snow character. I suspect this may be a little underdone and lake enhanced inversion heights upwards of 6-9 kft may be able to provide additional moisture into the DGZ. Within the broad northerly flow aloft, several shortwave pivoting through the Upper Great Lakes may be able to help boost localized convergence over the lake and thus help drive dominant band structures that are capable of producing locally heavier snowfall. Plus, with an unfrozen Lake Nipigon to the north, seeder-feeder action from Nipigon may also help play a role in dominant banding into the central UP. Given the warm lake temp average near +9C, I also suspect the greatest snowfall accumulations will be found, as per usual, in the higher terrain of the Michigamme Highlands of Marquette and Baraga counties where the lake modified airmass is harder to penetrate and terrain enhancement occurs the best. Temps should be cold enough to allow snow to fall at the immediate lakeshores, but warm lake-modifed air, less frictional convergence, and gusty northerly winds 15-25 kts will displace the best totals inland. The latest ensemble guidance is trending upward in terms of snow totals, with the latest NBM suggesting a 40% chance 48 hr totals >4" in the central UP high terrain ending Saturday night. The Euro Ens paints a 50-70% chance for at least 6" across the same area/timeframe. Given how poor the NBM handles LES, it wouldn't shock me to see the total/probs increase over the next few cycles.

AVIATION /00Z TAFS THROUGH 00Z MONDAY/

Issued at 610 PM EST Sun Nov 8 2026

Satellite imagery reveals plenty of lower-level lake clouds across the UP, though any precipitation is mainly staying east of SAW. There is enough drier air at lower levels to keep ceilings at low- end VFR, mainly hovering around 3500-4500ft, but some brief drops down to MVFR are not out of the question at CMX and SAW through the night (around 30-50% chance). VFR prevails Monday as lake clouds clear out and midlevel cloud cover fills in. Otherwise, expect northwest winds to continue to gust to around 20-25kts at CMX and SAW the next few hours, then winds turn light overnight before shifting out of the south at around 5-10kts late morning. Gusts up to 20kts will be possible into the afternoon.

MARINE

Issued at 302 PM EST Sun Nov 8 2026

Lake Superior: Gusty NW winds 25-45 kts and significant wave heights 10-15 ft (both greatest in the central and eastern lake) slowly diminish tonight through early Monday morning from west to east, falling below gales in the east half around midnight local. Another clipper system tracks north of the lake Monday night into Tuesday, however this system is weaker and gale potential remains low (10-30% chance). High pressure keeps winds seasonally benign the rest of the forecast.

Northern Lake Michigan and northern Bay of Green Bay: NW winds 20-30 kts fall below 20 kts early tonight, remaining near or below 20 kts through the remainder of the forecast.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... None. Lake Superior... Gale Warning until 7 PM EST this evening for LSZ244>247.

Gale Warning until 10 PM EST this evening for LSZ248>251- 265>267.

Lake Michigan... None.