textproduct: Marquette

KEY MESSAGES

- Dry weather continues through the end of the week with highs in the low to mid-70s today and near 80 on Friday.

- A quick round of showers and storms moves through Friday night into early Saturday morning.

- The potential for active weather returns early next week as a Colorado Low moves towards the region.

DISCUSSION

Issued at 232 AM EDT Thu Sep 10 2026

Early morning water vapor and RAP analysis shows midlevel troughing over the Great Lakes, extending southward from a deeper trough moving east of Hudson Bay. An embedded shortwave is apparent over the Dakotas, but this looks to drop well south of us later this morning. Rather a dry airmass is allowing for mostly clear skies, and with winds falling back somewhat quicker than guidance previously suggested, some patchy fog is not totally out of the question over the next few hours across the interior UP. Otherwise, temperatures currently hover in the lower to mid 50s over the western half of the UP and the upper 50s to the east; expect lows to range in the mid 40s (west) to lower 50s (east).

Today, high pressure expanding over the Plains extends ridging into the Great Lakes, with a quiet and sunny day ahead as highs peak in the 70s away from Superior, and in the mid/upper 60s lakeside. Temperatures fall back into the 40s to lower 50s under clear skies tonight, then climb higher again Friday as the ridge axis slides eastward and we become situated over increasing SW flow ahead of our next approaching trough (more on that shortly). Expect highs in the lower 80s for most Friday afternoon.

Meanwhile, seasonably strong 500 mb zonal flow evolves Fri/Sat over the northern tier of the western half of the CONUS. A lead shortwave trough ejecting across the Upper Midwest will foster a compact surface low/front over the northern Plains, near which convection is expected to erupt Friday afternoon/evening within a plume of moderate instability. The front sweeps across the UP Friday night with rain and thunderstorms expected for the west half, weakening with eastward extent along with the instability. Severe weather is not expected at this time due to the waning instability. It will be more seasonable and dry behind the front on Saturday and likely into Sunday.

Looking ahead into early next week, there are indications that a wetter pattern evolves as a Colorado low develops in response to deep troughing over the northern Rockies. Good poleward Gulf moisture advection is modeled (mean PWATs in the 1.5-1.75 inch range locally per the LREF, which is toward the 95 pctl of climo), which will be lifted atop a low-level frontal boundary to provide a potentially long-lived period of rainfall Monday into Tuesday in the Upper Midwest. Cluster analysis shows the main mode of variability is tied to the overall amplification of the encroaching trough and downstream ridge, with a more (less) amplified height field favoring a wetter (drier) solution. About a quarter of the LREF members are slower with the trough, which would favor another dry day on Monday, as well. Regardless, LREF indicates a 50-60% chance of accumulating 1" of rainfall by Tuesday evening, and a 20-30% chance of 2". Medium range AI-based convective hazards forecasts indicate any severe weather risk remains to our south during this period.

AVIATION /06Z TAFS THROUGH 06Z FRIDAY/

Issued at 642 AM EDT Thu Sep 10 2026

VFR conditions continue over the terminals as SKC generally holds. Light winds today driven by the lake breeze increase from the south late tonight as a low pressure approaches the area. We may flirt with LLWS criteria near dawn on Friday at IWD (highest chance) and CMX. However, confidence is too low at this time to include it in the TAFs.

MARINE

Issued at 232 AM EDT Thu Sep 10 2026

Lake Superior: NW winds continue to gust to around 20-25kts over the eastern half of the lake through the pre-dawn hours, then gusts fall back below 15kts across the entire lake by mid morning. Waves, starting at around 3-7ft (highest east), fall back to around 1-3ft in the eastern half of the lake by the afternoon while coming in around a foot to the west. Winds gusts pick up out of the SW late tonight into Friday, with gusts increasing to 20-25kts across most of the lake after midnight. Higher gusts to 30kts will be possible between the Keweenaw and Isle Royale. Gusty southerly winds persist into Saturday, slowly decreasing from west to east while shifting over to the NW Sunday. Wave heights build to around 3-6ft by Friday night, slowly decreasing below 3ft Sunday.

Northern Green Bay and northwestern Lake Michigan: NW wind gusts up to 15kts this morning continue to decrease after sunrise, while wave heights fall below a foot. Winds increase out of the south for Friday and Saturday, when gusts to 20-25kts will be common. Wave heights increase to around 4-5ft by Friday evening, then fall back below 3ft Saturday evening while winds shift over to the NW and decrease.

MQT WATCHES/WARNINGS/ADVISORIES

Upper Michigan... Beach Hazards Statement until 5 PM EDT this afternoon for MIZ006.

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