textproduct: Gaylord

KEY MESSAGES

- Warm/humid weather continues into at least Friday...

- Storm chances continue through Friday; some could be strong to severe.

DISCUSSION

Issued at 406 AM EDT Thu Jul 2 2026

PATTERN SYNOPSIS/FORECAST:

Longwave pattern remains troughing-west, ridging-east...with a ridge over central Canada giving the impression of an omega block...bounded by an upper low over the PacNW and a 561dm upper low slowly churning its way across Manitoba/Ontario toward Hudson Bay. 596dm 500mb ridge centered over western KY. SW 100kt upper jet stretches from Lake Superior into central Quebec along the perimeter of the ridge...with subtle cold advection aloft over Lake Superior attm; plume of anomalously moist air (pwat of 1.75 on the evening sounding here at APX) beneath the upper jet, stretching from IA to Georgian Bay...with upstream return flow still feeding Gulf moisture into the Plains, esp with southerly LLJ strengthening after dark out here. Steep lapse rates aloft across much of the central US...with 700mb 12C isotherm stretching from WY to S. MI and even into PA at 5z. Mid/low-level confluence from W WI across the EUP attm, with convective activity over WI tracking E/NE from WI into northern MI along a theta-e gradient stretching from MN to the Straits...with 20- 35kt SW/WSW LLJ. Core of the hottest air (24C 850mb temps) to our south over OH/IN...with a little low-level cold advection across Ontario (850mb temps over Manitoba only as cool as 8-12C). Surface cold front associated with this stretches from central Ontario back through southern ND; aforementioned theta-e gradient is some semblance of a surface trough/cold front that in turn stretches eastward to southern Quebec. Surface temps/dewpoints across northern MI at this early hour (5z) still in the balmy low to mid 70s (T) /upper 60s to lower 70s (Td)...though we did not get quite as warm yesterday thanks to midday convection (highs largely in the 80s to near 90F).

PV maxima runs across the top of the ridge axis today...ultimately flattening things to some degree. Appears that omega-block idea may try to give more than just an impression over Canada as troughing settles in on either side of the continent with that ridge hanging on over northern Canada into the weekend. Expectation is this setup will leave a weak-ish BCZ across the international border for late week, albeit high-bridged...with some energy looking to track across the Upper Midwest Saturday night into Sunday...which may try to cut off over the Great Lakes going into early next week. Overall pattern expected to remain somewhat in motion...with Canadian ridging looking to migrate eastward next week as some energy tries to track across central Canada. This could punt a shortwave ridge axis into the Great Lakes for the start of next week...with potential for subtle height falls going toward midweek as the pattern takes on a bit more zonal of an idea than the current situation. Bottom line...expect things to remain seasonably warm and active overall through the period.

FORECAST DETAILS...

Storm threats today...Quite a bit of uncertainty about today/tonight. Think the most likely scenario is for some storms to redevelop/continue this morning, with the best shot generally along and south of M-32 where the outflow boundaries from the early morning activity should lie. However...do have some concerns about development across the EUP as the tail end of the PV maxima and cold advection aloft scrape along the top of the ridge axis this morning. Will need to watch for additional development this afternoon, especially if we don't get much activity to redevelop this morning. This latter scenario lends potential for the lake breeze to develop today, which could serve to focus convergence, though do have concerns that warming 500mb temps across the area may limit the amount of CAPE today vs the last couple days, particularly if the boundary layer struggles to recover more than expected today (greater shot at holding onto some capping). Deep layer shear could hold on enough through the day today to keep some storm organization in the realm of possibilities; winds should again be the primary concern, especially if any upstream convection gets organized, given the deep warm layer that should melt a lot of hail...though expect it would be reasonable to keep an eye on any funky boundaries for spin-ups. Heavy/torrential rain will remain a concern, with pwats remaining above normal and potential for storms to move rather slowly/redevelop over similar areas again...particularly with some localized areas having seen several inches of rain in the last 48- 72hrs.

Tonight...signals for an area of convection to develop somewhat east- to-west across some portion of the area, though whether it develops further north or further south is uncertain. My current feeling is that the southerly solution will prevail and the action will remain largely south of M-32 where there should be confluence aloft...though there are some signals for a perturbation slipping along the perimeter of the ridge again. Low-level jet strengthens a bit again (albeit relatively meager, around 20-30kts again)...but there could be enough deep layer shear for organization again to keep the threat of severe weather around, not all that dissimilar to tonight.

Warm/muggy conditions continue...Think today will be similar to yesterday, with temps still peaking around 85-92F, warmest likely near Saginaw Bay, barring convective debris keeping a lid on temps again. Dewpoints should be pretty similar as well...generally in the upper 60s to around 70F or so again...which puts our heat index generally 85-90F north, and 90-100F south, again, highest near Saginaw Bay/Gladwin area. Heat advisory is admittedly marginal, but will hang onto it for now given that we're moving into day 3 of prolonged warm/muggy conditions and think there is potential for it to get a bit warmer/more muggy than is in the current forecast. Overall, not a ton of change in the airmass (save for perhaps across the EUP, depending on how far south the influence of the troughing across Ontario is able to get)...and anticipate similarly warm/muggy conditions will continue through at least Friday, though we may trend a bit cooler/drier through Saturday/Sunday. A brief warmup looks to be on tap for the start of next week with that shortwave ridge axis slipping in from the west...though not expecting the dramatically warm potential like we were for this past week.

Storm chances will hang on into Friday as the song largely remains the same across the region, though the top of the ridge should start to shunt southward with time. We remain in a marginal risk for severe weather on Friday, which seems reasonable attm. Rain/storm chances will continue Saturday as that bit of energy tries to cut across the Upper MS Valley, looking to slide eastward into the region going into Sunday. Think we will need to keep an eye on what develops upstream, particularly Saturday night into Sunday morning...though quite a bit of uncertainty how this feature evolves (a more wound-up, negatively tilted feature would be favor a very active night Saturday night, though this is most likely the most aggressive/worst-case-scenario solution attm).

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/

Issued at 507 AM EDT Thu Jul 2 2026

Another challenging taf period with very low confidence in convective evolution. Overall, mainly VFR conditions are expected with just some higher based cumulus and some passing convective blowoff cirrus. Again, will simply need to monitor radar trends for specific impacts and timing of any activity into our taf locations today and tonight. Future amendments more than anticipated. Light winds this morning do become bit gusty out of the southwest and west later this morning and afternoon. Winds go light again this evening.

APX WATCHES/WARNINGS/ADVISORIES

MI...Heat Advisory until 8 PM EDT this evening for MIZ016>018- 020>036-041-042-097>099. MARINE...Small Craft Advisory until 8 AM EDT this morning for LMZ323- 341-342-344-345.