textproduct: Gaylord

KEY MESSAGES

- Heavy rain and strong/severe storms possible again today, especially this morning through early afternoon. Afternoon redevelopment possible.

- Rain/storm threat continues off and on through the weekend.

DISCUSSION

Issued at 350 AM EDT Wed Sep 2 2026

PATTERN SYNOPSIS/FORECAST:

Southwesterly flow aloft across much of the CONUS...from the Pacific to the Upper Midwest. PV maxima embedded in the flow over the Dakotas...upper low spinning to our northeast over central Ontario and filling as it does so...with more or less zonal flow aloft over the Upper Great Lakes between this an southern stream ridge axis still centered over the Mid MS Valley. We continue to tap both Pacific moisture, and a bit of Gulf moisture, though right now, most of the latter is focused near "Edouard" over southern TX... but still, pwats at or above 1.5 in in the region, with swath of 2+in pwats along deformation axis from the central Plains to SW MI and some weaker stability in place, particularly near Neb/SD/IA, where convection is blossoming as of 4z. SW-ly nocturnal LLJ is nosing into this area as well, further favoring the idea of convection there. Some thunderstorms have tracked across Whitefish Bay toward Soo Canada thus far, though, along the portion of the front/baroclinic zone associated with the northern stream upper low (dewpoints drop back into the 50s and 60s behind this...as opposed to the 70s ahead of it, even at 4z). Evening convection that developed on the lake breeze in NE Lower still tracking eastward across central Lake Huron at 4z, too...and airmass here in Lower MI remains juicy and somewhat juiced, instability-wise, though some radiational cooling is resulting in the usual near-surface nocturnal inversion and some CINH.

Expect upstream baroclinic zone/convection to buckle northeastward, with plume of deeper moisture likely to advect into the region along/ahead of the boundary this morning. Attm, appears some semblance of a cold front may drape into the area this evening/tonight as the cooler airmass to our north scrapes the area. In the meantime...this will leave the Upper Midwest in a col region tonight into Thursday, favorable for an area of renewed moisture pooling/frontogenesis...particularly as upstream system begins to cross the Plains. Will expect a return to juicy conditions Thursday into Friday as deep moisture focuses near and north of a boundary/warm front likely stretching from the Northern Plains into southern MI. Ridge axis appears to build to our west across the Upper MS Valley going into the weekend, and will need to keep an eye out for some warm advection activity...though we may get in on some ridging by later in the weekend as a northern stream system passes across north/central Canada and scrapes off the top of the ridge. Guidance continues to struggle with how this will evolve, though currently, solutions seem to be leaning toward the ridge axis prevailing over the Great Lakes, shunting the aforementioned northern stream system to our north...as troughing over the PacNW begins to eject early next week. This idea would support warm and unsettled weather continuing into at least the middle of next week, with potential for troughing to generally prevail over the western US/West Coast beyond this.

FORECAST DETAILS...

Rain/storms today/tonight... upstream convective complexes (noting a nice bow echo over southern MN at 5z) may try to hold together and track into our area through the remainder of the morning; think the better chance for more organized storms is just to our south as usual, though it's not out of the question it remains further north, given a more or less zonal thickness gradient into the region, and a SW flow component that may offset Coriolis effects that would otherwise veer it south. At the very least...we could/should end up in the stratiform portion of whatever globs of convection track eastward this morning. Worth noting that there is still some semblance of a boundary draped across the Straits region attm (6z) with lower dewpoints north and dewpoints still solidly in the 70s across most of northern Lower (most of Lower MI as a whole, for that matter), and this could serve to focus some additional development this morning further north than anticipated, across the Tip of the Mitt region and perhaps the EUP....noting there are some signals for gravity waves out there this morning, too, to further throw a convective wrench into things. Best shot for any stronger storms this morning through midday would likely be near and south of M-72. Think this area could also be worth keeping an eye on through the afternoon, particularly if there is enough diurnal heating across the Saginaw Bay region early in the day (predicated on not too much cloud cover) to result in some improved instability there. This is largely where the Day 1 marginal risk for severe weather is located (generally near and south of a line from Alpena/Ossineke to Frankfort/Arcadia), and this seems like a reasonable idea. Guidance soundings suggest there is a chance the atmosphere recovers and destabilizes again this afternoon, especially in this region -- and given that dewpoints could easily remain in the 60s there this afternoon, this is not unreasonable...though if the northern boundary slows up and we do destabilize, this could focus storm chances further north this afternoon, too. Would need to keep a close eye on any afternoon redevelopment, as the environment could be more favorable for enhancement of low-level wind shear and spinny shenanigans with any lake breezes or lingering outflow boundaries, particularly as close to the front itself as we may remain today. All this being said...it's certainly not out of the question this morning's convection may stabilize the boundary layer enough for long enough to preclude much afternoon activity up here.

Primary concern regardless will be heavy rain, especially if anything remains slower to move and/or more east-west oriented. Strong winds are possible, particularly this morning if the upstream activity is able to remain congealed, though there may be some sub- cloud drier air this afternoon to support evaporative cooling/enhancement of downdrafts. Hail could be a possibility as well, given deep layer shear will remain strong and storms could remain organized and/or become organized again this afternoon. Suppose there is a chance for a tornado as well, as we may be close enough to the boundary for any interactions to result in enhanced low-level wind shear, especially toward Saginaw Bay if we are able to get our lake breeze going this afternoon.

Bottom line...definitely looking at heavy rain/storm concerns through midday across northern Lower, esp near and south of M-72, with wind/rain as the primary threat... and there is a probable threat of afternoon redevelopment, predicated on our airmass destabilizing again this afternoon...with this idea more likely toward Saginaw Bay; the afternoon activity could support all hazards.

Rain/storms Thursday-Friday...Think we could have a shot at a break in the action tonight into most of Thursday, though will be watching for deformation axis precip to redevelop to our west Thursday night into Friday, and this could lift into at least parts of the area (esp west of I-75). This time around, it's possible the better instability and storms could remain to our west, given that the warm advection appears to stay focused across the Northern/Central Plains and Upper MS Valley, rather than veering as quickly into the region as there is less of a distinct feature aloft to shove it eastward compared to our current status. Additionally, there are signals for high pressure to try to sneak back in from the northeast, which could allow drier/cooler air to ooze back into the region. Certainly close enough to keep an eye on things going forward, particularly for localized flooding concerns if we get any heavier rainfall today.

AVIATION /18Z TAFS THROUGH 18Z THURSDAY/

Issued at 1246 PM EDT Wed Sep 2 2026

Just a few lingering showers this afternoon under primary VFR CIGs. However, fog and low CIG development expected again tonight with IFR-MVFR (low chance for LIFR) conditions anticipated at most terminals. Improvement expected Thursday morning. Low confidence in additional shower/storms tonight, and have left that out of the TAF at this time.

APX WATCHES/WARNINGS/ADVISORIES

MI...None. MARINE...None.