textproduct: Marquette

KEY MESSAGES

- Isolated to scattered showers linger today, mainly over the eastern two thirds of Upper Michigan.

- Temperatures fall back into the mid 60s to upper 70s for the weekend, coolest near Lake Superior. Lower dewpoints will result in a more comfortable airmass on Sunday and Monday.

- The chance for showers and thunderstorms returns on Tuesday as a cold front approaches the area.

DISCUSSION

Issued at 307 AM EDT Sat Aug 1 2026

Early morning GOES WV imagery shows the mid level trough now over the Upper Mississippi River Valley with RAP analysis plotting the associated 1004 mb low now over northern IL. A cold front is pressing south over the CWA early this morning while the abundant moisture from yesterday begins to exit. With instability falling and deep moisture dissipating, shower activity is tapering down and thunder has ceased. That said, isolated to scattered showers closer to the low over the east half of the UP and northerly upslope drizzle are both possible today as a secondary cold front progresses south overhead. Low level moisture will remain high, possibly resulting in patchy fog, mainly over the east half this morning. Cooler temps today in the 60s and 70s, coldest near eastern Lake Superior. As the UP dries out for tonight under weak high pressure ridging, colder temps are expected in the mid 40s to upper 50s, coldest interior west.

Notably drier air can be expected for Sunday into Monday with dewpoints in the 50s, resulting in more comfortable conditions. Temperatures will be in the mid 60s to 70s on Sunday and upper 70s to low 80s on Monday (close to seasonal averages).

On Tuesday humidity will begin increasing ahead of an approaching cold front. Showers and thunderstorms may accompany the front on Tuesday but the risk for organized convection remains uncertain at this point in time, with global models showing lower instability and shear. It will fall back into the 70s for Wednesday behind the front with a rebound again on Thursday along with a slight chance for thunderstorms.

AVIATION /06Z TAFS THROUGH 06Z SUNDAY/

Issued at 120 AM EDT Sat Aug 1 2026

Precipitation is now mainly south of the TAF sites, with chances of further precipitation now 25% or less at all 3. The primary aviation impact will be the potential for low ceilings and visibility overnight at CMX/IWD with radiation fog formation and during the daytime at SAW with moist upslope flow. Recent model guidance has decreased confidence in dense fog at either CMX or IWD, with probabilities of IFR or less ceilings or vis peaking at around 35 percent. SAW has trended later with the onset of lower flight categories, but with much higher probabilities. By 13Z, the probability of IFR ceilings at SAW exceeds 50 percent with 40-50 percent chances of LIFR by the afternoon hours. VFR conditions are expected to return by 03Z as skies scatter out.

MARINE

Issued at 307 AM EDT Sat Aug 1 2026

The lake remains under a weak pressure gradient through the forecast, resulting in mainly light winds at or below 20 kts. Areas of fog may develop early this morning. Showers and thunderstorm are expected again on Tuesday but there remains uncertainty as to the the coverage and strength of the storms.

MQT WATCHES/WARNINGS/ADVISORIES

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