textproduct: Marquette

KEY MESSAGES

- Borderline elevated fire conditions expected to persist through the evening.

- Scattered rain showers are possible (20-45%)for Wednesday morning, with best chances in the southern tier.

- Seasonably warm weather will persist through the Labor Day Weekend, with high temperatures expected to be in the mid to upper 70s each day.

DISCUSSION

Issued at 312 PM EDT Tue Sep 1 2026

Above-average temperatures and breezy conditions are expected to remain over the area through this afternoon. In the western CWA, RH values in the low 30s indicate the potential for borderline fire weather conditions to persist through this time period. Tonight, the low pressure center currently over Ontario will pass to the north as it moves eastward toward Quebec.

This progression of the low is expected to return upper-level moisture over the area tonight, increasing PWATs to 1.00-1.25 inches by Wednesday morning. Chances for rain begin Wednesday around 13z, with the best chances (up to 45%) occuring between 15z and 16z in the southern portion of the CWA. Precipitation chances are expected to decrease and skies are expected to partially clear towards the early afternoon due to the return of drier upper-level air over the area as the Canadian low continues its progression eastward.

Much of the remainder of the week will be dominated by upper level ridging over the central CONUS and broad troughing over eastern Canada, leaving the Upper Great Lakes in a fairly benign northwest flow pattern between the two features. The influence of the ridge will be enough to keep temperatures above seasonal norms across the the UP through the period, with daytime highs staying in the mid to upper 70s and overnight lows generally in the mid to upper 50s through the weekend. Do not see any significant rainfall in the forecast beyond Wednesday, but a few disturbances embedded in the flow will at least keep some periodic shower chances around from Thursday into the weekend.

AVIATION /00Z TAFS THROUGH 00Z WEDNESDAY/

Issued at 717 PM EDT Tue Sep 1 2026

VFR conditions prevail for the duration of the TAF period. With drier air and slightly higher wind speeds, opted to leave out mention of fog tonight. There are, however PROB30s at IWD and SAW for rain showers around daybreak tomorrow morning. Expect winds to turn light and variable tonight.

MARINE

Issued at 312 PM EDT Tue Sep 1 2026

Lake Superior: Winds are expected to remain SW at 15-20kts over the west until 00z this evening, at which point they are forecast to drop to 10-15 kts and shift to a westerly direction. Winds over the east will remain largely southerly at 10-15 knots until around 02z tonight, when they are expect to shift SW. Wednesday, winds will begin westerly, shifting to northwesterly with the passage of the low pressure center to the north. Wind speeds across the lake are expected to remain under 15kts during this time. Wave heights are expected to remain under 3ft through Wednesday evening, although waves up to 4ft are possible between Isle Royale and the Keweenaw.

Northern Green Bay and northwestern Lake Michigan: Winds will remain southerly around 10kts through this evening. During the overnight hours, winds are expected to weaken to less than 5kts and become variable. Wednesday morning, winds remain around 5 kts in a generally southerly direction. Showers, and possibly a rumble of thunder, are possible Wednesday morning. Waves are expected to remain at or below 2ft through Wednesday evening.

MQT WATCHES/WARNINGS/ADVISORIES

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