textproduct: Gaylord

KEY MESSAGES

- Breezy Monday, with rain/storms later Monday into Tuesday morning

- Cooler Tuesday and beyond with frost/freeze concerns likely

DISCUSSION

Issued at 356 AM EDT Sun Apr 26 2026

PATTERN SYNOPSIS/FORECAST:

526dm upper low continues to swirl over the central Canadian Prairies, bumbled along by 100+kt WSW sub-tropical jet across the southwestern US...and a blocking ridge over Hudson Bay/514dm upper low off the East Coast of Canada...giving the northern stream that omega look. Across the central US...nebulous yet active...with cold front draping from a low over western Ontario down through MN and into KS, along which convective activity has focused. Cold front loops back through the TX Panhandle, into CO, and through central UT...along a confluence zone between the northern stream and southern stream out west...where one PV maxima swirls down the PacNW coast toward NoCal...and another upper low spins off the coast of SoCal; latter feature helping to buckle the STJ a bit more SW. Across the Midwest/Eastern US...upper ridging more or less hanging on over the Midwest, resulting in generally quieter weather/pressure rises in our vicinity for a change, though flow remains split between this and troughing over the southeastern US...with a BCZ stretching from TX to WV, along which the bulk of the moisture is focused. Some moisture is sneaking northward along the cold front into the Upper Great Lakes, around the perimeter of the mid-level ridge...just not making great gains in the low levels, as largely easterly flow across MI/IL keeps the return flow trapped across the Mid MS Valley. Here in the northern Great Lakes...not a pure/clean surface high by any means, as there is still low-level moisture trapped overhead (per 0z sounding...and looking out the window at the 1500ft cloud deck at 0z), though there is a fair bit of drier air aloft.

Ridge axis overhead today will begin to migrate eastward...as PV maxima off SoCal digs through the SW US into the southern/central Plains...driving surface pressure falls across the central US and MS Valley Sunday night. Will expect strong southerly/southeasterly flow on Monday ahead of this system...which should cross the Midwest Monday night into Tuesday; current signals point toward cold front/trough axis sweeping through Michigan at some point Tuesday morning as the surface low treks northeastward into Canada...leaving cooler, northwesterly flow across the Great Lakes in its wake. Another lobe of energy with the upper low will cross our area on Wednesday...likely driving a surface response over the OH Valley. This feature should bring colder air into the fray, as it will be more "in phase" with the northern stream flow upper low near Hudson Bay...with northwesterly flow aloft allowing for a feed of colder air from central Canada into the Midwest/central US for mid-late week, aided by another niblet dropping in Wednesday night/Thursday. Upstream flow will be largely split through the period, with southern stream niblets getting cutoff over SoCal and trying to slip into the southern Plains late this week...with much more progressive northern stream flow into the PacNW. This latter idea suggests we may have occasional periods where ridging may try to interrupt the cold flow, though it also appears the upper low over the eastern US will be slow to move out and leave the upstream pattern (including here in the Midwest?) a bit congested. Overall, signals point toward colder trends across the eastern half of the US for the end of the week, and perhaps beyond, if ridging is able to hold on more firmly over the PacNW coast going into next week, and keep the door propped open for cold air to funnel out of northern Canada.

FORECAST DETAILS...

Fire weather concerns Today/Monday...Today...expect we should dry out quite well today with the ridging overhead, esp for northern Lower, which, while highs will likely hang out in the upper 60s with a few spots around 70 at best...could leave us with afternoon RHs in the 25-35 percent range. Not impossible there could be enough low- level moisture hanging around to temper the drying a bit, at least initially...but think we should begin to mix out as the afternoon goes on. Of much more concern is Monday...with a) much stronger winds, and b) potential for warm temperatures. The question is, just how much will we be able to warm on Monday, and how long will we be able to hold onto the dry air? It's looking like mid-level moisture (even non-zero rain chances) could begin to overtake the region as early as 18z Monday from the west as much more absolute moisture forces its way in with time (pwats 1+in)...which suggests we may not have as much time as we'd like to maximize afternoon heating. South/southeast low-level flow will be strong...which would favor warmer, downsloping temps over NW Lower where clouds/rain could move in earlier. Additionally...have concerns the axis of maximum warm/theta-e advection will be to our west over WI, immediately ahead of the surface system on Monday. Antecedent dry conditions should hang tough east of I-75 on Monday, and this could also be where diurnal heating has a better shot at maximizing; thus, think this will be the area of greatest concern for fire weather conditions.

Strong winds Monday...Strong/tightly wound surface low to our west Monday supports sustained southeasterly/south-southeasterly winds increasing from 10-15kts to 15-25kts in the afternoon/evening, and not out of the question winds could be a bit stronger than this, even, where better channeling is possible (likely the Straits/Whitefish Bay). Winds aloft should also strengthen...upwards of 30-40kts in the afternoon and evening, and think there is a reasonable shot at these mixing down. LLJ could be even stronger overhead Monday evening into Monday night, which could support potential for strong winds with any convection in the area. Not impossible we could see a few areas reach wind advisory criteria (sustained 30mph/gusts 45mph) conditions Monday afternoon outside of any convection...and gales are likely on the lakes. Winds should slowly taper off Tuesday behind the front (strongest pressure gradient may remain to our north).

Rain/storms late Monday into Tuesday...As mentioned above, think it is possible rain may begin to encroach on western portions of the area as early as 18z Monday. Antecedent dry conditions should slow things down, esp the further east you go...and low-level theta-e advection may not be super favorable initially with the southeast winds along a southeast-northwest gradient...but top-down saturation does appear to win out with time. This idea also suggests we could end up more stable aloft than we would like for convective purposes, which is likely the primary reason we remain just outside the outlooked area for day 2 from SPC (better instability should remain to our south). Still...with this shortwave likely turning negatively tilted as it crosses us Monday night...worth keeping a close eye on for thunder concerns. Not impossible we could see a bit of warm- advection activity develop across NE Lower in the afternoon, as some guidance seems to hint at...but the bulk of the activity should be the evening/overnight into Tuesday morning when a dry slot may cross the area ahead of the cold front.

As far as heavy rain concerns...still quite a bit of uncertainty in where the maxima will end up given the anticipated convective nature. Anomalous moisture/moisture transport (pwats in the 1-1.25in range; IVT in the 99th percentile) with this very dynamic system remains a concern for being able to squeeze a lot of rain out over some area, perhaps quite efficiently, too. Overall synoptic pattern still has a Maddox Synoptic-Type look, further lending credence to the possibility of heavy rain somewhere in the Great Lakes (though potentially just to our south)...though fortunately, system appears reasonably progressive, which could keep the higher totals from sticking over any one area for too long. Prob guidance suggests the best shot at 6hr rainfall totals greater than an inch would be across NW Lower, and particularly W central MI...which fits the stereotypical convective outbreak pattern for northern Michigan (i.e., worst of it stays to our south and we get stratiform junk on the northern edge of things). Still...that stratiform rain could be a problem for areas across Manistee/Wexford counties in particular, where high water levels/flooding continues attm. Also watching potential for a rainfall maximum into part of the EUP Monday night, north of potential warm front.

Colder weather for the remainder of the week...Much colder air begins to funnel in behind the system Tuesday. Attm...Wednesday night through Thursday night appear to be the coldest periods...with 850mb temps falling below zero, supporting highs in the 40s (and perhaps struggling at that). This, with a typical 20-ish degree diurnal temp swing, would easily put overnight lows in the 20s...which will be a concern given that our growing season has begun (noting the amount of flowers and leaves starting to show up out there). Though we are yet not at our typical 125 Growing Degree Day (base 50) threshold that we typically look at for spring frost/freeze concerns...it is worth noting things are running ahead of normal, perhaps as much as a week or more ahead of normal across the area... and we are already close to 100 GDDs across our most sensitive ag area across NW Lower. Think Wednesday night may be the coldest, with a better shot at high pressure being overhead compared to Thursday night (potential for a PV max to be in the vicinity)...but multiple nights of sub-freezing (perhaps mid 20s?) temperatures look possible going through the latter portion of the week into next weekend.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 652 AM EDT Sun Apr 26 2026

Ongoing FG / BR this morning should scour out with time. Lingering low-level stratus will intrude on MBL and maybe TVC this morning before that too scours out. Result will be a transition from the ongoing varying MVFR to LIFR to primarily VFR by afternoon as CIGs constitute of some high cloud overhead. Light SE winds prevail 10kts or less. Just some high cloud carrying into tonight... trends are bearish on additional BR / FG development tonight as SE winds fail to decouple and even increase later tonight.

APX WATCHES/WARNINGS/ADVISORIES

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