252
FXUS63 KAPX 081015
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
615 AM EDT Tue Sep 8 2026

.KEY MESSAGES...

- Rain chances move into northern Michigan later today, peaking
  this evening through Wednesday morning.

- Increasing winds this afternoon, peaking Wednesday afternoon.

- Mainly dry weather expected during the second half of this
  week, potentially extending into next week.

&&

.DISCUSSION...
Issued at 235 AM EDT Tue Sep 8 2026

Pattern / Forecast Synopsis:

500mb ridge axis that has been overhead the last few days in the
process of being forced south and eastward by a broad, deepening
Pacific borne wave and associated surface low pressure in the
process of occluding / closing off over Montana and the Dakotas,
along with the southern Canadian Prairies. Surface high pressure
overhead also beginning its dispatching stage right as this system
continues its north and east progression into central Canada,
eventually tracking into the James Bay region by Thursday. The
system`s associated surface cold front will gradually be forced
through the region... albeit slowly... as flow turns more zonal and
parallel to the boundary. Result will be a 24-36 hour period of
deep moisture advection into the upper Great Lakes that should
support atmospheric profile saturation, and perhaps have just enough
lift in the region to force a convective element into the picture
too.

In the wake of the system, ridging and surface high pressure to
temporarily restore meteorological order amid a cooler and drier
airmass Thursday and into Friday. Ridging will be amplified by
another Pacific wave bull-rushing into the Pacific NW / British
Columbia Thursday and Friday... with guidance depicting this wave as
closing off and progressing eastward through the northern Canadian
Prairies into Hudson Bay by the conclusion of the weekend, and
forcing its associated cold frontal boundary through the region,
perhaps returning briefly unsettled weather to the region ahead of a
cooler and drier stretch next week.

Details:

Rain / Thunder Chances through Wednesday: Advancement of deeper
moisture will initially struggle across the region today, with the
more prolific convective response being confined to the western Yoop
through the St. Croix River Valley in WI / MN through late
afternoon owing to better elevated instability... which also
aligns with where today`s Marginal Risk for severe has been laid
down by SPC. Instability will be lacking across APX-Land this
afternoon owing to thicker cloud cover hampering lapse rates aloft
along with low-level dry air suppressing low level buoyancy within
the profile. Nonetheless, as this deeper moisture plume makes its
advance, there will be a window for some high-based light rain
showers. Wouldn`t be overwhelmingly surprised to see most areas
hold dry for the majority of the day, especially the farther south
one goes... but, the status quo changes in the evening through
overnight. Core of the deepest moisture finally makes its way
through the region, accompanied by a pre-frontal warm nose that
coincides with nocturnal stability in the low levels.

As such, weak elevated instability (to the tune of 200-400 measly
J/kg) within a zone of strong isentropic lift to manifest some
convective showers across the region tonight. As pointed out by
previous forecaster, thunder chances may be hampered by limited
buoyancy higher in the profile within this instability plume.
Convective allowing guidance continues to struggle getting buoyancy
much past -10C likely places thunder coverage on the isolated side.
That being said, with such a juiced atmosphere, some of these
convective showers may be capable of some efficient downpours,
especially as we go later into the overnight and activity peaks.
Overall, most areas on average probably see 0.10-0.25" of rain this
evening through late Wednesday morning... but there can easily be
some embedded 1.00"+ rainfalls... the coverage of which probably
holds much more isolated the farther north one goes.

Trending Windy by Wednesday: Increasingly pinched pressure gradient
to make its way through the region with this system... initially
hampered by the presence of a warm nose Tuesday evening / night...
probably keeps a cap on gusts at 25mph. As the front makes its
passage through the day Wednesday, increasingly cooler and drier air
within the dry slow of the system to noticeably increase as momentum
transfer is maximized. With 925mb flow 25-35kts, certainly possible
to see some 40mph wind gusts late Wednesday morning through the
afternoon... especially near the lakeshores and the highest interior
terrain. Not enough there just yet for land based wind headlines...
but will need to watch areas near Whitefish Bay as some guidance
wants to have 925mb flow pushing 40kts up there owing to that long
Lake Superior fetch. For now, wind headlines will be confined to
marine zones.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 614 AM EDT Tue Sep 8 2026

Cigs will gradually lower today into tonight as top-down saturation
continues (although VFR cigs will likely be maintained through much
of the period). A few showers may fall out of this mid level
overcast this afternoon, with much better rain chances arriving
overnight. May also see a few embedded thunderstorms as well. Some
support early Wednesday morning for the development of MVFR
producing cigs...especially at KCIU and KPLN. Initial light winds
become a bit gusty today into tonight out of the south and
southwest.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory from 5 AM Wednesday to 5 PM EDT Thursday
     for LHZ345>348.
     Small Craft Advisory from 5 AM to 11 PM EDT Wednesday for
     LHZ349.
     Small Craft Advisory from 2 PM this afternoon to 11 PM EDT
     Wednesday for LMZ323-341-342-344>346.
     Small Craft Advisory from 2 PM this afternoon to 8 AM EDT
     Thursday for LSZ321.
     Small Craft Advisory from 8 AM to 11 PM EDT Wednesday for
     LSZ322.

&&

$$

DISCUSSION...HAD
AVIATION...MSB