textproduct: Marquette

KEY MESSAGES

- Dry weather expected to persist into next week with above normal temperatures.

- Humidity will fall into the 20-25% range over interior locations during the daytime hours through early next week along with warm temperatures, resulting in at least borderline elevated fire weather conditions.

- Next chances of showers and thunderstorms is in a window from Wednesday night to Saturday, but uncertainty in the details is high.

UPDATE

Issued at 333 AM EDT Sun May 31 2026

Persistent omega block pattern continues to influence Upper Michigan weather with no changes to ongoing forecast at this time. RAP analysis/water vapor imagery early this morning still shows ridging from Manitoba/Ontario southward through the Lower Midwest. Meanwhile, closed lows have pushed farther into New England and the Mountain West. As a result, the dry, warm conditions in easterly flow will be conducive to a fire weather threat into next week. With lighter winds today, however, no SPS headlines will be issued for elevated fire weather conditions. However, one will likely be needed tomorrow with an uptick in easterly winds and gusts up to 20 mph. Meanwhile, widespread RH values in the mid to upper 20s percent will prevail across much of the interior U.P. So, those planning to have outdoor fires should pay attention to the conditions and local area burn restrictions. Further out, long range ensembles continue to trend toward a pattern shift by Tuesday as the ridge weakens and the Mountain West low transitions to a trough, tracking through the Great Lakes Region late in the week. Some much needed rain could help mitigate the current fire threat.

DISCUSSION

Issued at 216 PM EDT Sat May 30 2026

Afternoon GOES-East imagery shows a remarkably clear sky over the UP today with fair-weather cirrus just across the state line and over far western Lake Superior. Aloft, the upper air pattern is textbook omega-blocked, with the center of the ridge extending from IL to Manitoba and the closed lows over New England and Wyoming respectively. Being downstream of the ridge axis, the surface high is centered over James Bay and the eastern half of Hudson Bay, with broad northerly to easterly flow off the Canadian Shield leading to dry air and the clear skies leading to temperatures warming above normal. While the dry air is concerning for fire weather purposes, the winds are decreasing (only a few stations gusting above 15 mph) and vegetation is in a greened-up state.

Little change in the forecast for Sunday as compared to today. The high pressure will be centered more over the Great Lakes, but will be weakening, so little change in the temperature forecast is noted. The continued relaxing of the pressure gradient will create light and variable winds and CAMs show prominent lake breezes off of both Lakes Superior and Michigan penetrating well inland. RHs look to be dry once again with inland RHs falling to the 20s percent, though the lack of strong winds will keep fire weather concerns limited.

As the high over the Great Lakes continues to weaken, yet another high forms over Hudson Bay as the 500mb pattern exhibits extremely little change through Monday. As such, yet another day of summerlike temperatures and RHs falling to the 20s in the interior will occur. The wind pattern will more resemble today than Sunday as the winds will be more consistently out of the east to northeast and the deterministic NBM suggests wind gusts in the afternoon around 20 mph in the interior west, which could necessitate another fire weather SPS.

By Tuesday, the LREF mean 500mb chart suggests that the weather pattern will finally begin shifting as the eastern closed low shifts off the Newfoundland and Labrador coast while the western low shifts north to Montana. This will cause the ridge to flatten significantly, and while there is spread in the details, the global deterministic suite agrees that the western low becomes a trough that tracks over Lake Superior and northern Ontario throughout the PM hours of Thursday to Friday PM. This will give us our next chances of precipitation, though global models are notoriously poor at determining the breakup of a blocky pattern, so confidence is only high enough to provide a broad window of unsettled weather. NBM highs settle into the 60s and 70s instead of 70s and 80s for the later portions of next week. LREF mean SBCAPE values of around 250 J/kg in the afternoons for Thursday and beyond will give at least some potential for thunderstorms mainly in the interior west, though it is far too soon to tell if there is any severe potential. The chances for a wetting rain will be a welcome relief for those concerned with fire weather as chances of 0.1"+ of precip by the end of Thursday ranges from around 35% in the east to around 70% in the west with widespread 50-70% chances of over a quarter inch of rain by midday next Saturday.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Issued at 105 AM EDT Sun May 31 2026

VFR is expected through the duration of the 6Z TAF period under the influence of high pressure. With no fog concerns and only few high clouds passing overhead, the focus is on winds. Variable to calm winds are expected through this morning at SAW/CMX; light southeast winds at IWD. Lake breezes yield wind shifts at all sites this afternoon around 7 to 10 kts. Winds turn calm for tonight.

MARINE

Issued at 216 PM EDT Sat May 30 2026

Blocked weather pattern aloft leaves high pressure from the Upper Great Lakes to Hudson Bay through the weekend and first half of next week, leading to an extended period of time where virtually all of the lake will be in mild conditions with gusts sub-20 kt. The exceptions will be this evening and Monday evening, where northwesterly flow accelerates down the western arm of the lake to 20-25 kt, briefly driving 3-4 ft waves. As the pattern breaks up in the midweek and progresses, the next chance for gusty conditions and some thunderstorm potential is late next week, though model spread by that point decreases confidence in the details. Chances of wind gusts exceeding 25 kt is around 10-20% for any given period between Thursday night and Saturday.

MQT WATCHES/WARNINGS/ADVISORIES

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