textproduct: Marquette

KEY MESSAGES

- Rain exits the eastern UP this morning, yielding another warm and dry day with temperatures in the 70s.

- Rain chances have shifted further south away from most of the area through Thursday.

- Breezy conditions are expected as winds shift out of the west- northwest Thursday and Friday. Gusts of 30+ mph are likely near Lake Superior from the Keweenaw east to Whitefish Point.

- Temperatures drop back into the 60s on Thursday and cool to near seasonal normal values in the upper 50s to low 60s through the weekend. Frost and freeze concerns are likely from Thursday night onward.

DISCUSSION

Issued at 259 AM EDT Wed Sep 30 2026

Early morning radar shows a batch of welcome rain showers moving through the eastern half of the UP on the nose of a 850 mb jet as a weak shortwave trough skirts the Upper Great Lakes ahead of large scale troughing centered upstream over central Canada. Rainfall amounts have generally been light overnight, with a few spots near the Wisconsin border approaching a quarter inch but most other locations generally limited to a tenth of an inch or less. In terms of the large scale pattern, RAP analysis and water vapor imagery reveal split flow over North America, with the aforementioned low over Canada and a strong surface reflection approaching Hudson Bay while a cutoff low remains over the Desert Southwest. The bulk of the UP will stay dry between these two features today once the current rainfall exits to the east later this morning. This will set the stage for another warm and pleasant fall day as a weak warm air advection regime supports highs in the mid 70s across much of the area again today, with morning clouds giving way to a few breaks of sunshine by the afternoon.

Thursday looks to remain dry over the UP as a low associated with the southern stream energy spins up over the Plains and lifts northeast towards the Great Lakes. The vast majority of guidance keeps any rain associated with this system well to the south over Wisconsin and Lower Michigan, with low end chances for any measurable precip generally confined to areas along the Lake Michigan shoreline. Temperatures look to run about 8-10 degrees cooler across the area on Thursday with the passage a cold front. This will also bring breezy conditions near Lake Superior as winds shift west-northwesterly behind the front, bringing gusts of 30+ mph from the Keweenaw eastward to Whitefish Point. Breezy conditions persist into Friday as temperatures continue to moderate into the upper 50s to low 60s. Expect some chilly nights beginning Thursday night as strong high pressure builds into the region from the northern Plains and brings clearing skies and more optimal radiational cooling processes. Will likely be dealing with some renewed frost/freeze concerns into the weekend as lows dip near or even below freezing in a few interior locations. A weak clipper type system then brings additional precipitation chances to the area late Saturday into Sunday.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 744 AM EDT Wed Sep 30 2026

LIFR/IFR cigs are present this morning as low level moisture is trapped underneath a subsidence inversion behind a midlevel cold front. Expecting these low cigs to persis through much of the morning before lifting to MVFR/VFR by afternoon. Tonight, fog development is possible given lightening winds and lingering low level mositure.

MARINE

Issued at 259 AM EDT Wed Sep 30 2026

Lake Superior: A 30-40 kt low level jet is bringing south-southwest winds of 20-25 kt to eastern portions of Lake Superior this morning, supporting a few small craft headlines through later this morning in the nearshore waters east of Marquette. Winds drop below 20 kt by this afternoon as the system exits to the east. Winds shift west- northwesterly tonight into Thursday behind a passing cold front, and although gale probabilities have dwindled to around 15% on Thursday, this still should provide another round of solid 20-25 kt winds and small craft headlines across a wide swath of the lake given cold air advection and strong pressure rises as high pressure builds in from the west behind the front. Northwest winds remain gusty into Friday, with gale chances increasing to 25-40% and wave heights building to 3- 6 ft over the east half of the lake. Winds go light Friday night into early Saturday with the increasing influence of surface high pressure, but another clipper low arriving late in the weekend brings another round of stronger winds into Sunday.

Northern Green Bay and northwestern Lake Michigan: A weak system passing to the north and an associated 30-40 kt low level jet will maintain south-southwest winds of 20-25 kt and small craft headlines for the Bay of Green Bay and adjacent northern waters of Lake Michigan today. Winds slacken tonight into early THursday and then eventually turn northwesterly around 15-20 kt behind a passing cold front, remaining in that range through Friday. Lighter winds with high pressure on Saturday give way to 15 kt southerlies on Sunday with the arrival of a clipper low to the north over Lake Superior.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Beach Hazards Statement through this evening for MIZ014.

Lake Superior... None. Lake Michigan... None.