textproduct: Marquette

KEY MESSAGES

- Mainly dry weather persists through early next week with high pressure over the area.

- High temperatures trend slightly upward into the upper 60s to low 70s through the end of the week.

- A few rain showers may graze the western UP this weekend, but more widespread chances for rainfall hold off until mid next week.

DISCUSSION

Issued at 215 AM EDT Thu Sep 24 2026

Skies remain mostly clear across Upper Michigan early this morning under the continued influence of high pressure extending westward into the Great Lakes from Quebec. This has allowed for another night of efficient radiational cooling, although temps are running a touch higher than the last few nights owing to light southerly low level flow. This should keep any frost confined to the coldest interior spots through daybreak. Also seeing a few reports of fog over northwest WI early this morning, and do expect at least some patchy fog development over parts of the UP this morning as dewpoint depressions continue to narrow. Finally, extensive high level cloud cover is noted upstream over Minnesota, and expect that to eventually spread over our area today in conjunction with a weak shortwave trough crossing the region. Recent model runs have continued to back off of the already minimal precipitation chances with this feature, now keeping the forecast completely dry across the west today as HREF has chances for any measurable rain in the single digits. Temperatures will mostly be in the mid to upper 60s again this afternoon, with dewpoints mixing out nicely. This will allow RH values to drop into the low to mid 40s in interior locations, especially across the eastern UP where approaching cloud cover will hold off the longest. Do not anticipate any significant fire weather concerns given winds staying below 15 mph.

Upper level ridging rebuilds over the region Friday into this weekend, yielding continued benign weather with highs climbing into the upper 60s to low 70s into the early part of next week. Another weak disturbance could graze the western UP late this weekend, but guidance is trending in a similar direction to today's shortwave in terms of precipitation, capping PoPs at a slight chance with the NBM depicting only around a 25% chance of measurable rainfall over roughly the western third of the UP late Saturday into Sunday. The forecast therefore remains dry across the bulk of the area well into next week. Ensembles continue to show good agreement on the ridge finally breaking down over eastern Canada by the middle of next week. This will open the door for a trough to swing through the Great Lakes and bring the next chance for widespread rainfall, although details are still of course very much up in the air at this point in the forecast.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

Issued at 140 AM EDT Thu Sep 24 2026

Primarily VFR conditions are expected during the 6Z TAF period at the TAF sites as high pressure continues to extend overhead. The exception to this is at SAW this morning when BR/FG development is anticipated, starting around 11Z and lifting after sunrise. A slight increase in forecast confidence warranted the addition of a TEMPO group for IFR VIS and CIG between 12-14Z. LIFR VIS probabilities only range between 15-35%. During the day, broken high clouds increase gradually from the west. Otherwise light southerly winds around 5 kts increase to around 8 kts today with gusts between 10-15 kts; winds shift east at CMX this afternoon.

MARINE

Issued at 215 AM EDT Thu Sep 24 2026

For Lake Superior: High pressure keeps winds mostly below 20 kt through much of the next week. Expect southerly winds of 10-15 kt today, gustier across central and eastern portions of the lake. Winds fall back below 10 kt across the entire lake Friday while waves decrease to 1 foot or less. Southerly wind gusts of 15-20 kt develop Saturday ahead of a weak system, diminishing back to 10-15 kt on Sunday and 5-10 kt on Monday. Some model guidance is hinting at a potentially stronger system tracking through the region later next week, but confidence in that scenario is very low at this time.

For the Bay of Green Bay and Northern Lake Michigan: Southeast winds around 10-15 kt today go very light from the south on Friday. Wave heights subside to below 1 foot by Friday morning. Winds remain below 10 kt into the beginning of next week.

MQT WATCHES/WARNINGS/ADVISORIES

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