textproduct: Marquette

KEY MESSAGES

- Temperatures in the mid 60s to upper 70s today, coolest near Lake Superior. Lower dewpoints will result in more comfortable conditions.

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

DISCUSSION

Issued at 306 AM EDT Sun Aug 2 2026

The CWA remains fairly quiet as drier air under northerly flow subsides over the UP. This is supported by sprawling weak high pressure ridging from Hudson Bay/northern Quebec across northern Ontario, Lake Superior, Upper MI, WI, and MN, continuing down into the Plains. The trough responsible for the heavy rainfall observed over parts of the UP on Friday has now made its way to IN, with an associated 1005 mb sfc low beneath it. GOES WV imagery highlights a positively tilted ridge over the northern plains moving east toward the Great Lakes.

The rest of today remains dry and quiet as ridging weakens, but remains mostly stationary overhead. Any patchy dense fog in the far west clears out for plenty of sunshine today. Temperatures will be slightly cooler again in the 70s with mid to upper 60s near Lake Superior. With afternoon mixing, dewpoints fall into the low 50s allowing for much more pleasant humidity. The drier air mass, mostly clear skies, and weak high pressure ridging tonight allow for radiative cooling to yield a chilly summer night. No frost/freeze concerns, but lows are expected in the 40s in the interior with lakeshores settling into the the upper 40s to mid 50s. While not in the forecast, would not be surprised if a few RAWS sites dipped briefly into the upper 30s tonight.

Dry weather persists into Monday under high pressure, but with temperatures warming back into the upper 70s to lower 80s as the mid level ridge continues eastward over the western Great Lakes and 850 mb temps warm to 15-17 C. The next chance of precipitation then comes on Tuesday as a trough approaches from the northwest and drives another cold front through the UP. This could also bring another round of thunderstorms to the area, but severe potential is TBD given uncertainty over timing and degree of instability and shear. Temperatures look to drop down into the 70s again on Wednesday behind the front, but will quickly recover back into the 80s on Thursday as additional systems bring more chances for precipitation towards the end of the week.

AVIATION /06Z TAFS THROUGH 06Z MONDAY/

Issued at 119 AM EDT Sun Aug 2 2026

After spending the bulk of the day LIFR, SAW has cleared out to VFR, but satellite imagery does show patches of FG elsewhere in Marquette County, so further FG cannot be ruled out tonight (10-20 percent chance). CMX is also free of FG, though satellite does indicate some patches of low stratus or FG around the Portage Canal. IWD has been LIFR for the last few hours with a stubborn fog bank which is around 70 percent likely to linger through 12Z. Otherwise, expect mostly quiet weather for this TAF period with mainly light winds (10 kt or less) out of the north to northeast.

MARINE

Issued at 306 AM EDT Sun Aug 2 2026

Weak high pressure ridging extending overhead through Monday keeps winds below 20 kts as dry weather holds. Patchy dense fog over the western shores clears out this morning. Showers and thunderstorm are expected on Tuesday, but there remains uncertainty as to the coverage and strength of the storms. What is becoming more likely is for southerly winds to increase Monday night to around 15 to 20 kts with gusts up to 25 kts into Tuesday morning. In the wake of the cold front, westerly winds may continue in the 15 to 25 kt range, but fall below 20 kts over the east half of the lake by Tuesday afternoon. Winds settle below 20 kts lakewide for Tuesday night, likely holding at or below 20 kts the remainder of the forecast (70% chance).

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... None. Lake Superior... Dense Fog Advisory until 8 AM EDT /7 AM CDT/ this morning for LSZ240.

Lake Michigan... None.