175
FXUS63 KAPX 260337
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
1137 PM EDT Tue Aug 25 2026

.KEY MESSAGES...

- Thunderstorms likely through the day on Wednesday, a few
  strong storms and locally heavy rainfall the main concerns.

&&

.DISCUSSION...
Issued at 110 PM EDT Tue Aug 25 2026

Pattern Synopsis and Forecast:

Upper trough and induced low pressure system will traverse the Upper
Midwest tonight, moving eastward with time on Wednesday into N MI.
Pressure gradient increases some with the relatively "weak" low
pressure system, and thus breezy conditions are anticipated through
the day. Main story will be the convective evolution and what that
might look like.

Warm advection coupled with upper forcing/divergence within an
environment characterized by sufficient moisture and instability
will result in scattered to numerous thunderstorms on Wednesday,
beginning west of 75 in the morning up into the E UP, then migrating
and redeveloping eastward during the afternoon hours. Any stronger
storm will be capable of locally gusty winds and hail. Any severe
threat looks rather isolated and localized in nature, given the high
moisture content and modest shear (25 kts of bulk 0-6km, little more
0-8km, although that can be enough to generate transiently strong
storms). Given trough orientation/forcing and instability axis,
northeast lower into eastern upper will "likely" see the best
opportunity for locally heavy rainfall with training storms. That
being said, the atmosphere will be primed with ~1.4"-1.5" PWATs,
significant moistening in the low to mid levels, and seemingly more
than enough instability for any storm to produce locally heavy rain.
Given the low LCLs, weak low level shear, and subtle backing of the
low level wind field in areas, an isolated tornado cannot be
entirely ruled out but it will not be the primary concern. Limiting
factors will be if instability ends up being much less than progged
and/or if convection well to our northwest generates a significant
cold pool and ruins the convective potential for most of northern
lower MI as the boundary is forced eastward quicker. Nevertheless,
the signal is there within the suite of hi-res guidance for heavy
rain in spots. Localized flooding not out of the question if the
ingredients come together just right. Activity diminishes through
the night with the loss of daytime heating and the main forcing
moving eastward.

Troughing continues to dig down across Ontario late week, impinging
lower heights across the Great Lakes Region. Consequently, cooler
temperatures are anticipated Thursday into Friday, although close to
seasonable for this time of year. Cannot rule out some light showers
as well during this time frame and mildly breezy winds.

Heading into this weekend and early next week, ridging builds across
the South to Southeast, troughing moves west to east across the N
Plains and vicinity, and a more overall zonal structure takes hold
for N MI. Consequently, low pressure system to the west will advect
moisture eastward into the Midwest, with rounds of rainfall
possible. Most likely timing for rain and storms will be Sunday into
Monday as moisture advection coincides with upper support. Plenty of
uncertainty in regards to the details though. High temperatures seem
to hold steady in the upper 70s to low 80s outside of the typical
day to day variability given storms and cloud cover.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1134 PM EDT Tue Aug 25 2026

No big changes from 0000Z TAF issuance...just some adjustments
for timing as initial band of broken showers moves across
central Upper and into Lake Michigan. Marginal low level wind
shear expected during the early morning hours...with an
increased threat for showers/thunderstorms with MVFR conditions
and occasional IFR ceilings/visibilities in heavier
precipitation. Convective coverage should become more scattered
after 1800Z but expect mostly prevailing MVFR ceilings.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement through Wednesday evening for MIZ025-
     031-095.
MARINE...Small Craft Advisory until 10 PM EDT Wednesday for LHZ345.
     Small Craft Advisory from 11 AM to 10 PM EDT Wednesday for
     LHZ348-349.
     Small Craft Advisory until 10 PM EDT Wednesday for LMZ323-341-
     342-344>346.

&&

$$

DISCUSSION...JLD
AVIATION...JPB