textproduct: Marquette

KEY MESSAGES

- Near-normal temperatures today give way to warmer weather to wrap up the work week.

- The next significant chances of precipitation and thunderstorms arrive Friday evening afternoon and evening. Severe weather is not expected and rainfall will be limited.

DISCUSSION

Issued at 322 AM EDT Wed Aug 5 2026

Early morning RAP analysis features an upper-level low pressure spinning near Hudson Bay and extending troughing into the north- central CONUS. Meanwhile, midlevel riding is present over much of the western CONUS, peaking over the Four Corners. At the surface, high pressure is centered over the Central Plains, extending surface ridging into our neck of the woods. Closer to home, the cold front that brought spotty convection to the area yesterday is draped just southeast of the UP. Plenty of lower to midlevel cloud cover is present over the eastern and central UP, but more breaks in the clouds are apparent over the far west. Clouds should continue to slowly erode from west to east today as the front slowly moves eastward. Expect temperatures, bottoming out mainly in the 50s early this morning, to peak in the 70s this afternoon.

Surface high pressure slides over the Lower Midwest Thursday, while aloft, additional midlevel shortwaves rotate through. That said, model soundings remain too dry for anything more than some stray cirrus grazing the area. Increasing southwest flow on the backside of the surface ridge and ahead of another approaching Canadian shortwave will bring in a surge of warmer air, allowing temperatures to climb from morning lows in the 50s to highs in the 80s for most - even upper 80s in our typically warmer southerly downsloping spots.

The aforementioned shortwave reaches the area Friday, with an associated cold front sweeping through during the afternoon and evening amid a more moist airmass and an anomalously strong LLJ moving overheard. Along with this, the NBM shows up to 50% chance of SBCAPE greater than 500 J/kg along the WI border Friday afternoon, and 30 knots of 0-500mb shear. NBM probability of 6-hr precip exceeding 0.1" is around 50% for at least some point on Friday afternoon and evening, and the 90th percentile of 6-hr distributions top out at 0.6" at this point in time. All told, severe weather is not expected for this event at this time.

Further out, differences in LREF clustering in 500 mb heights begin around Day 6 (Aug 8-9) in the timing and strength of trough entering into PNW from Pacific (though strength of this trough is so weak such that the question is not 'how strong?' but rather 'trough or zonal?'). That said, the influence on this region for days 6-9 are all very similar, with the Canadian low and Four Corners high still in place leading to local NW'ly mid-level flow.

AVIATION /12Z TAFS THROUGH 12Z THURSDAY/

Issued at 719 AM EDT Wed Aug 5 2026

VFR conditions for duration of TAF period. Nonetheless, there is a 20% chance that some patchy FG could form at IWD and SAW early Thursday morning. However, confidence remains too low to include mention in TAFs. Otherwise, expect light winds to shift over to the west this afternoon, then to the south tonight.

MARINE

Issued at 322 AM EDT Wed Aug 5 2026

Winds out of the west to southwest continue to fall back below 15kts this morning, and remain light until this evening. Winds turning to the south pick up to around 15-20kts tonight, then continues to increase to around 20-25kts Thursday and up to 20-30kts Friday. Winds fall below 20kts Friday evening. Waves remain below 2 feet before building to 3.5 feet by Friday morning, then decrease to 1-2 ft by Saturday afternoon.

MQT WATCHES/WARNINGS/ADVISORIES

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