textproduct: Gaylord

KEY MESSAGES

- Grungy/foggy today (possibly clearing this afternoon) and perhaps again tonight; much cooler/more seasonable.

- Warmer with rain/storms late Monday into Tuesday.

- Cooler weather ahead into early May.

DISCUSSION

Issued at 326 AM EDT Sat Apr 25 2026

PATTERN SYNOPSIS/FORECAST:

Zonal flow across the SW US, with area of deformation/confluence stretching from northern CA to the central Plains. Broad 523dm upper low centered over southern Saskatchewan stretches from eastern British Columbia to the W UP of MI, with 850mb temps as cold as -8C or colder across central Canada. Ridge axis stretches from Hudson Bay to GA, becoming pinched off over eastern Ontario/Lower Great Lakes...between this and another upper low downstream, just off the northeast US Coast...giving a bit of an omega look to the northern stream. Flow across the SE US still a bit split...with a disturbance now well off the east coast of Florida. Deeper moisture (pwats 1+in) starting to clear northern Michigan...now focused across the Lower MS Valley into the eastern Great Lakes as upstream PV swings through WI with drier air aloft in its wake (denoted by sharp back edge to deeper cloud cover over central Lake Superior into the EUP as of 2z). Most of the rain/precip activity now focused to our east, along a decaying occluded front stretching from filling 1001mb surface low over eastern Saskatchewan...down to a triple point near Saginaw...with more convective activity through the OH Valley and down into the Lower MS Valley...along and ahead of a cold front stretching from said triple point through southeast MO into southern OK (organized/strongest convection down here). Warm front with our system stretches from Saginaw to near Washington DC and off the coast. Meanwhile...upstream...end of the aforementioned cold front stretches up to a low over northeastern CO and westward through NV...with signals for a surface cold front trying to develop from here to MN as of 0z, the boundary between seasonably mild air and seasonably colder air oozing south along the Rockies.

Lobe of PV swings through today...with some semblance of upper ridging and potential subsidence trying to return and break up the grunge a bit. Upper low continues to swirl over central Canada, swinging one more lobe across the Upper Midwest tonight into Sunday, though impacts from this may remain to our west. Nebulous flow here in the Great Lakes could support another night of foggy/grungy conditions given antecedent low-level moisture from yesterday that may not be able to mix out too well today. By Saturday night/Sunday...troughing will be digging across the SW US, resulting in pressure falls across the central US that should intensify return flow through the MS Valley into the Midwest going into the start of the work week. Sharp PV maxima tracks through the Upper Midwest Monday night into Tuesday, with signals for this feature to turn negatively tilted; this suggests a very dynamic system, and not surprised that SPC has been highlighting (for at least a couple days) areas of concern to our SW for Monday. Expect we will need to monitor this situation for thunder potential as well as heavy rain potential, noting that strong southerly flow is supportive of a good Gulf tap. (It should also be breezy.) Cooler weather floods in for midweek and beyond...with potential for a few more lobes of troughing to swing through the trough axis and reinforce the idea of colder/northwesterly flow for a change going into late week next week.

FORECAST DETAILS...

Grunge/fog today/tonight...think it will remain grungy and cool today...with a better chance of drizzle/showers this morning into early afternoon as a subtle niblet of PV swings through. Things should try to break up/scatter out this afternoon as drier air tries to work its way in...with signals for this to occur from the lakeshores inland, potentially leaving the interior higher terrain in grunge-land into the afternoon. However, it does appear we will try to mix up into a strato-cu deck, and not impossible a few sprinkles could be squeezed out with these. Otherwise...north(ish) flow down Grand Traverse Bay through this afternoon could enhance convergence just enough to keep the grunge/drizzle/sprinkles present in the Traverse City area compared to elsewhere in that area. Winds should slowly start to diminish going into tonight, and will expect a night of radiational cooling, land breezes, and fog/low-stratus, particularly given that we probably won't mix out the boundary layer moisture added yesterday, esp down toward Saginaw Bay where they had more rain (and it is more reticent to permeate the soil). This idea also suggests overnight lows will struggle to totally crash like they would if we had a drier boundary layer around...though some areas could certainly see temperatures near or slightly below freezing.

Rain/storms Monday/Tuesday...dynamic system expected to lift out of the central Plains and into the Upper Midwest later Monday into Tuesday...attm, most likely crossing our area sometime on Tuesday. Would expect some convective activity to develop ahead of the low to our west/southwest, and will need to keep an eye on how this will evolve as it approaches us...but some guidance soundings suggest we may struggle to get better instability in our area till closer to the cold front passage Tuesday. This suggests we could end up a little more stratiform Monday night, which, combined with anomalous moisture transport/pwats in the presence of good forcing with a warm front in the vicinity...does lend some concern for better rainfall potential again. Setup is somewhat similar to a Maddox Synoptic Type heavy rainfall pattern, though whether the focus for this ends up over us or slightly out of our area is still in question.

Warm Monday...Strong southerly flow ahead of the system could promote more warming than we are currently expecting. Most guidance attm generally suggests highs in the upper 60s to lower 70s, but if warm advection is more aggressive here and we are able to mix more deeply...850mb temps could support highs reaching into the mid 70s; S/SE flow downsloping could boost temps further than that in some localized areas, most likely in the Traverse City to Manistee vicinity. Not impossible mid/high clouds approaching from the southwest could limit temperatures to some degree, though. If the expected incoming moisture struggles against antecedent dry air more than expected, fire weather concerns could come into the fray, particularly with stronger winds in play (potential for sustained 10-20kts, perhaps gusting as high as 25-35kts in the afternoon).

Colder temps ahead... In the wake of the Monday/Tuesday system...will expect temps to tumble back toward normal for late April (normal highs in the mid to upper 50s; normal lows in the mid 30s). Quite a bit of uncertainty in how exactly the pattern evolves for the middle/late portion of the week...but if we end up with any periods of high pressure at night with this cooler air mass in the region, frost/freeze conditions could certainly become a concern. Perhaps the one upside is that the cooler daytime highs should limit the amount of growing degree days that can be accumulated, which should limit excessive furthering of the growing season. Overall signals in the longwave pattern currently support potential for colder weather to try to ooze into Midwest (though there is still quite a bit of uncertainty in how this evolves attm). If the pattern ends up a little more blocky over the North Atlantic, with potential for troughing to overtake the northern Pacific...certainly possible we could hang onto overall troughing/colder conditions...which is what CPC guidance is currently highlighting...and think frost/freeze concerns will be at the forefront as we go into early May.

AVIATION /18Z TAFS THROUGH 18Z SUNDAY/

Issued at 122 PM EDT Sat Apr 25 2026

Widespread MVFR/IFR cigs with some terminals still seeing vis reductions. Conditions will improve to VFR for all sites by 20z as cigs lift and scatter. Winds remain AOB 10kts and generally N/NE. Conditions will degrade again tonight after 06z for some terminals. BR/FG and low cig chances return for all sites with the best confidence for IFR/LIFR conidtions at KCIU/KPLN/KMBL. FG/BR and low cigs will likely lift and scatter quicker Sunday morning, with most terminals seeing improving conditions by 16z.

APX WATCHES/WARNINGS/ADVISORIES

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