textproduct: Marquette

KEY MESSAGES

- A few lake-breeze driven showers and thunderstorms are possible (up to around a 20-30% chance) in the interior west and central UP this afternoon. More widespread chances for showers and thunderstorms return for Thursday through Saturday. Severe weather is not expected over the next few days.

- High temperatures increase well into the 80s on Thursday, then fall back into the 70s from Friday into the weekend.

DISCUSSION

Issued at 324 PM EDT Wed Jul 29 2026

Today's upper level pattern features benign northwest flow on the periphery of strong ridging anchored over the central CONUS. GOES visible satellite reveals mostly clear skies across Upper Michigan and Lake Superior as of mid afternoon as surface high pressure persists over the region, with temperatures warming into low to mid 80s in most locations away from the lakeshores. A few of the more excitable CAMs have continued to depict a few showers and thunderstorms popping up on the lake breeze later this afternoon, which remains plausible given around 500 J/kg SBCAPE over the central and western UP per SPC mesoanalysis. Have thus held onto 20- 30% chance PoPs in the forecast through the remaining daylight hours, although hourly HRRR updates continue to keep us dry for the rest of the day. Will continue to keep an eye on satellite and radar trends to see if anything pops up through the afternoon, but either way do not expect any strong to severe storms given weak shear and rather limited instability.

Temperatures trend upward on Thursday as the ridge axis acquires a positive tilt and shifts eastward to the Great Lakes, yielding 500 mb height rises and 850 mb temps warming to 18-20 C. This will correspond to highs in the mid to upper 80s over much of the area, with a few spots pushing 90 near the WI border. This will once again yield some modest instability and a 20-30% chance for showers and thunderstorms as a pair of disturbances over northern Ontario and the Northern Plains, respectively, approach late in the day. The southern stream disturbance will move across Lower Michigan on Friday and interact with a cold front extending from the low over northern Ontario, bringing increased rain and thunderstorm chances to the UP on Friday as high temperatures dip back into the 70s. Chances for a wetting rain of at least a quarter inch range from 50-70% across the western and central UP through Friday night per the NBM, with closer to a 30-50% chance in the east. A few showers and thunderstorms could linger into early Saturday in the wake of these systems. Do not expect any strong to severe storms for any of these periods as shear remains weak for the next few days.

Sunday into Monday favors drier weather a high pressure builds back into the region, with temperatures looking to climb back into the 80s for much of next week. Another approaching trough will bring increasing precipitation chances again towards the middle of next week, but details are sparse at this time.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 125 PM EDT Wed Jul 29 2026

VFR conditions will prevail for the duration of the TAF period. Still cannot rule out some lake breeze-induced convection later this afternoon at IWD and SAW, but probabilities remain too low to insert mention. Winds will be light and westerly.

MARINE

Issued at 324 PM EDT Wed Jul 29 2026

Expect winds to remain below 20 kt for much of the next week amidst benign weather. Weak troughing moving back into the region on Thursday will bring chances for a few thunderstorms over Lake Superior and northern Lake Michigan through Saturday. but do not expect any of these storms to be severe.

MQT WATCHES/WARNINGS/ADVISORIES

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