539
FXUS63 KAPX 260959
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
559 AM EDT Wed Aug 26 2026

.KEY MESSAGES...

- Strong storms and heavy rain possible today

- Lingering showers Thursday, and perhaps beyond

&&

.DISCUSSION...
Issued at 314 AM EDT Wed Aug 26 2026

PATTERN SYNOPSIS/FORECAST:

Broad ridge axis restrengthening over the PacNW...as 568dm 500mb low
swirls over western Manitoba near the MN border, resulting difluence
over the Upper Midwest and parts of Ontario...with a second PV max
digging south into northern Manitoba attm, and a slight bit of a
warm nose/wraparound moisture between these two features. Wad of
moisture beneath the swirly across the Midwest/Ontario, with pwats
generally ranging from 1.2 to 1.5 in, highest right ahead of a
niblet of energy swinging across the western UP as of 3z where some
convection has been taking place...and is becoming somewhat
disconnected from greater wad of deep moisture from the Mid MS
Valley/Central Plains down into the Gulf Coast...with splitting flow
in the mid/low levels in this area. Warm, moist advection across the
Upper Midwest on SW/SSW low-level flow...slowly pressing eastward
across WI and the central Yoop. Surface reflection of the upper
swirly is an occluded low positioned over western Ontario, with a
cold front draped from here down to KS...and warm front stretching
toward the Keweenaw and central Lake Superior as of 0z. A second
cold front drapes from ND to Hudson Bay, just behind aforementioned
low...with stronger northerly flow over central Canada.

Shortwave trough swings across the Upper Great Lakes today with
attendant surface system and convection; lobe over northern Manitoba
punches SSE into the Lower Great Lakes and scrapes us Thursday into
Friday. Heights try to build eastward into the Upper Midwest going
into the end of the week with increasing warm advection out of the
Plains...with decreasing influence from upper low that looks to
strengthen over eastern Canada. Another bit of PV tracks near the
US/Canadian border this weekend into early next week (timing a
little unclear attm), and attm appears to track just to our north,
with a pattern shift in the works as troughing digs into western
North America for a change. This idea, if it holds, would indicate
potential for a warming trend across the eastern US toward the
middle-end of next week...though we still have a lot of time between
now and then to see how things change.


FORECAST DETAILS...

Heavy rain potential today...think the setup remains favorable for
heavy rain, with pwats up toward 1.5in, freezing levels up around
700mb or so, and lack of flow likely leading to slower storm
motions/longer potential for residence time over an area. Currently,
still expect the heaviest rain (potential for greater than an inch)
will be across the EUP closer to the better synoptic forcing, and
perhaps NE Lower as we go into the afternoon/evening with potential
for a couple rounds of storms and perhaps a bit more of an E-W
component to the flow, a little more parallel to the boundary.
Naturally, any storms will be capable of producing localized heavy
rainfall, and thus, there could be some hotter spots outside of the
aforementioned areas.

Severe storm potential today...Finally starting to see some
convective development closer to our area by 7z, along/ahead of a
couple boundaries that have been tracking eastward across WI all
night...perhaps even a shallow outflow boundary crossing N Lower
during the 6z hour, per a subtle N-S line in radar reflectivity near
Kalkaska/Bellaire. Anyway, this suggests we are finally starting to
destabilize, and will therefore need to keep a close eye on the next
3-6, 4-8hrs, with this first round of warm-advective showers and
storms moving through. Think the better axis of instability is to
our southwest, though, and think this will likely stay to our
southwest (per a redeveloping line near ARX early this morning,
tracking along the thickness gradient across southern WI). Would not
be entirely surprised if all of this ended up splitting and focusing
more to the north across the EUP and more toward GRR today, but will
see. Better instability reaches us around 12-15z into the remainder
of the afternoon, though based on guidance soundings, it may remain
mostly elevated for quite some time, with a warm nose in the mid-
levels...and we may struggle to actually get typical surface based
CAPE in many areas till perhaps late afternoon...except for perhaps
our southeast corner where there is a better shot at breaks in the
clouds and diurnal heating. (Interestingly, soundings across parts
of the Yoop suggest that while we may warm enough to overcome the
warm nose...it may remain too moist and stable in the low-levels for
parcels to accelerate off the surface.) Attm, appears deep-layer
shear increases this afternoon into this evening ahead of a front
(or two) draping across the area, and this could allow for
development of some stronger storms, especially for NE Lower, this
afternoon into this evening (18-23z). We may in fact see a secondary
front/trough drop in this evening, around or after 0z, and keep the
threat of stronger showers/storms going after dark. Wind and hail
remain the primary concerns, with the potential for discrete
convection and perhaps some upscale growth...but the moist low-
levels and that discrete convection potential do make me wonder
about isolated spin-ups.

Another punch of cool air aloft late tonight into Thursday will
likely keep a few showers/drizzle around the area, similar to the
other day, with temperatures again running on the cooler side of
things (though not quite as cold as it was over the weekend).
Unclear attm if this idea will hang on long enough into Friday to be
a concern...but by later Friday, we may be starting to look at our
next shot at warm advection activity approaching from the
west/southwest.

&&

.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 558 AM EDT Wed Aug 26 2026

Shower/ storm coverage is expected to increase west to east
this morning then become more scattered by this evening, with an
increased threat for MVFR conditions and occasional IFR
ceilings/visibilities within any heavier precipitation. Have
kept the marginal low-level wind shear early this morning for
northern Lower terminals. Winds will be gusty out of the south-
southwest becoming more westerly by this evening, then northwest
by Thursday morning. Low clouds with perhaps some showers/
drizzle look to linger into Thursday with pockets of VFR to IFR
conditions expected through the issuance period.

&&

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

&&

$$

DISCUSSION...FEF
AVIATION...NSC