textproduct: Marquette

KEY MESSAGES

- A couple batches of showers and storms move through the UP today. Strong storms are not expected.

- Dry weather returns Monday, followed by additional showers and storms on and off through midweek. Strong to severe storms are not expected.

- Temperatures come in near normal through the rest of the forecast period.

DISCUSSION

Issued at 245 AM EDT Sun Aug 9 2026

Early this morning, GOES WV imagery shows broad mid level troughing across central Canada which largely will not change until mid next week, yielding quazi-zonal flow over the Upper Great Lakes. This means that through early next week, precip chances will be supported by diurnal instability and driven by transient shortwaves/frontal boundaries. One such shortwave is currently moving into Minnesota, while at the surface, a weak frontal boundary is sinking over northern Minnesota and Lake Superior and kicking off an initial round of showers. Weak elevated instability (<500 J/kg) is analyzed over the area with strong shear (~50 kts), so thunder can't be ruled out as convection continues to kick off closer to home, but strong to severe storms are not expected. This initial round hangs out mostly over Lake Superior and the Keweenaw. PoPs expand to the rest of the UP the remainder of the day as diurnal instability builds, the front continues to sag over the CWA, and a upper level jet streak passes overhead. Instability will be run of the mill for meager summertime convection (mean values well below 1000 J/kg) with healthy bulk shear up to 40 kts. Given lackluster moisture and forcing, severe storms are not expected. CAMs are not in great agreement on coverage and timing of showers and storms following this morning's batch, reflected in an unimpressive 20-50% chances for rainfall amounts exceeding 0.25 inches per ensembles.

Expect an otherwise quiet and partly to mostly cloudy day with temperatures rising in the 70s for most, and some isolated spots peaking near 80.

Dry weather returns for tonight and Monday as weak surface ridging recovers. Lows dip into normal temps in the upper 40s to upper 50s. The rest of the forecast sees a slow trend to slightly cooler than normal temps as highs trend toward upper 60s to mid 70s for the end of the work week with lows in the 40s to mid 50s. Shortwaves Tuesday and Wednesday bring low chances for showers and storms (mostly 15- 30% chance), then drier weather is favored into the weekend as stronger high pressure returns.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 729 AM EDT Sun Aug 9 2026

Showers and storms currently moving through IWD have brought some erratic gusts as well as occasional MVFR restrictions, but conditions improve over the next couple of hours as storms exit the area. Then, mainly VFR is expected at all terminals through the rest of the daytime hours. Additional showers may develop this afternoon, with the best chances at SAW, but there is low confidence in these leading to restrictions. Also can't rule out a few rumbles of thunder to accompany showers, but chances are low enough (15-20%) as to not warrant inclusion in TAFs. Overnight, there is a potential for fog and low stratus to develop once again, with the highest confidence in MVFR/IFR restrictions at SAW. Still, restrictions will not be ruled out at IWD and CMX. Expect winds to remain fairly variable throughout the forecast period, and to come in below 10kts apart from in thunderstorms.

MARINE

Issued at 245 AM EDT Sun Aug 9 2026

Lake Superior winds continue to gust to near 15-20kts over the northern and eastern portions of the lake early this morning. Winds settle further to 15 kts or less after daybreak. Rain showers developing over the lake may lead to additional fog development into tonight. With the exception of northeast winds gusting up to 25 kts Thursday morning near Granite Island, winds likely (75% chance) remain below 20 kts lakewide the remainder of the forecast through next week.

SW winds over northern Bay of Green Bay and northern Lake Michigan remain below 15kts this morning. Winds increase to 15-20 kts while shifting more southerly this afternoon, then quickly fall off for tonight. Winds and gusts likely (75% chance) remain 15 kts or less the rest of the forecast through next week.

MQT WATCHES/WARNINGS/ADVISORIES

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