textproduct: Gaylord

KEY MESSAGES

- Grungy into tonight

- Strong system late week could bring gusty winds and heavy rain concerns along with cooler weather for the end of the week/weekend.

DISCUSSION

Issued at 247 PM EDT Tue Oct 13 2026

PATTERN SYNOPSIS/FORECAST:

595dm upper level ridge over the southern US, generally centered over east TX. General troughing over the western half of the continent with a 555dm upper low trying to get cut off over the western US...as northern stream energy zips right along through southern Canada...with more upper energy across central Canada to its north on the nose of a 100kt upper jet. 120kt SW oriented upper jet stretches from the Four Corners region up into the Upper MS Valley with zonal flow across the Midwest/Great Lakes region. Quite a moisture plume present this morning, with pwats 1.5-2in (or more, in the case of the S Plains/Lower MS Valley) all the way up into IL/IA and southern Ontario near its associated Great Lake. Pwat of 1.51in on our 12z/13 sounding is a new record for this date here, and we are certainly socked in in the low-levels...with fog and low clouds across much of the area, continuing to flood in behind a cold front swinging through from the west behind a bit of positively tilted energy that crossed the region overnight into this morning. Attendant surface low sits over GT Bay as of 12z...with cold front draping back into KS...and stationary/warm front stretching across northern Lower MI, eastward into northern NY. 850mb temp gradient from 0C over ND to +20C over SW Lower MI. Westerly(ish) LLJ leading to some subtle cold advection across the Upper Midwest into northern MI, and some signals of LL moisture trying to mix out upstream... but aforementioned stationary boundary and cloud cover holding tight here through 15z.

Energy to continue to slide by to our north through the rest of the day into tonight...allowing the boundary to slowly drape south through the area with time. Zonal boundary should remain stretched across the central/eastern US...but will be looking for the ridge upstream to build eastward Wednesday ahead of that upper low over the Four Corners...leaving us generally under the influence of subsidence and high pressure for midweek. The Pacific should spit another PV max eastward midweek...and current signals are for this to try to absorb that southwest upper low which should also start to move eastward a bit. Current expectation is for this to occur just upstream over the Upper Midwest...but we will be in the vicinity of lingering east-west baroclinic zone, leaving concerns for a potent surface low to congeal/spin-up over the Great Lakes Thursday into Friday. Think primary concerns with this feature are heavy rain and strong winds to wrap up the work week...though it will be cool again behind this. High pressure looks to build in for the weekend, with signals pointing toward a return to ridging across the eastern US as troughing digs into the western US again early next week.

FORECAST DETAILS...

Grungy into tonight...Grungy conditions likely to continue with low- level moisture hanging on. Falling temps aloft through the afternoon/evening should support some overlake instability, particularly across the EUP, where there is a better chance of showers hanging on tonight on north/northwest flow. We may struggle to fully mix out the low-level moisture through much of the day on Wednesday, per guidance soundings, but think cloud bases will rise a bit compared to today. Do have concerns for fog to hang on at times, particularly Wednesday night as high pressure attempts to move in...when winds should lighten up...but think we will hang onto some low-level moisture from last night's rain and any of today's drizzle.

Heavy rain concerns Thursday into Friday...hard to ignore the signals for a plume of highly anomalous pwats potentially around 2in, which would be +4 standard deviations above the mean. Given the dynamic system in play...both from the standpoint of a sharp trough for better PVA, as well as jet dynamics, with right entrance region of an anomalous upper jet (potentially 120-140kts)...do think heavy rain will be a concern somewhere across the Midwest/OH Valley region. For now...guidance signals the focus for the better pwats and subsequent moisture transport are to our south in the OH Valley, perhaps scraping southern MI, where there is a better chance for either a pivot point and/or multiple rounds of rain. However, I can't help but wonder about something developing further north, on the cold side of the boundary, particularly as we deal with that northern stream bit of energy swinging in and potential for an inverted trough/occluded front over the area. If the pattern evolution ends up with the northern stream trough scooping up the upper low just upstream of us, resulting in a bit more of an negative tilt to the incoming system...would have a greater concern for more robust precip (storms?) across the region, including perhaps in our region. Certainly worth keeping an eye on as we go forward.

Strong winds late week/weekend...developing surface cyclone looks to become tightly wound as it crosses the region, with pressure gradient strengthening in our region between this and anomalous surface high over the western US later this week. This signals a strengthening of W/NW winds (perhaps to eventually N), strongest Thursday night into Friday; winds should taper off a bit going into Saturday, but should remain on the breezy side (though not as much as Thursday night into Friday). Some deterministic progs quite easily suggest potential for sustained winds in the 10-20kt range during the day Friday, esp over the waters; main focus for strongest winds would be the northern shore of the Yoop and north/northwest- facing coastlines, particularly along Lake Michigan. Secondary trough axis looking to drop in at some point during the day with the troughing aloft...which should enhanced cold advection and gust potential...and dynamic setup could suggest some isallobaric input to winds/gusts, though not necessarily clear at this time (at least for us). Low-level jet looks to run between 30-40kts or so, and think this is a reasonable idea for gusts attm, as we should pretty easily mix this down. Sounding-derived probabilistic guidance suggests a very strong probability of gales on Friday out on the lakes, and stronger winds would not be impossible.

Southwest winds may strengthen again going into the latter half of the weekend as a system crosses central Canada, though perhaps not quite as strong as Thursday night into Friday... and there is also a touch less agreement in guidance on how far south the pressure gradient will tighten compared to Thursday night-Friday.

First snowflakes of the season Friday night????...with colder air mass moving in Friday night into Saturday (1000-500mb layer thickness falling below 540dam), would not be entirely surprised if a few snowflakes mixed in among the lingering showers/lake effect rain showers that will likely be in the area as 925 and 850mb temps fall below 0C as early as Friday afternoon. The most likely shot at this idea would be in the EUP, but not impossible it could get as far south as the interior higher terrain of northern Lower. Fortunately the cold air mass does not appear to last long, and we should already be warm advecting by Saturday/Saturday afternoon.

AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/

Issued at 140 PM EDT Tue Oct 13 2026

MVFR/IFR and some LIFR conditions continue as FROPA moves through this afternoon. Low cigs and BR/FG will last through 06z for most terminals, with MVFR after persisting through the end of the period due to low cigs. Low chances for impactful BR to return overnight after 10z. NE/N winds of 5 to 10kts will linger through the night, occasional G15kts will be possible through 00z and after 14z.

APX WATCHES/WARNINGS/ADVISORIES

MI...None. MARINE...Small Craft Advisory from 1 AM to 8 PM EDT Wednesday for LSZ321.