257
FXUS63 KAPX 120344
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
1144 PM EDT Fri Sep 11 2026

.KEY MESSAGES...

- Shower/thunderstorm chances along a passing cold front Saturday

- Cooler with some small rain chances Sunday

- More substantial rain event arrives Monday night/Tuesday;
  heavy rainfall potential.

&&

.DISCUSSION...
Issued at 309 PM EDT Fri Sep 11 2026

Primary Forecast Concerns:

Shower/thunderstorm chances along a passing cold front Saturday:
Surface cold front lying across northwest Ontario/northwest
Minnesota/southeast North Dakota at early afternoon is forecast to
propagate east through tonight...into the upper Great Lakes Saturday
morning...and across northern Michigan Saturday afternoon/evening.
Narrow theta-e ridge runs ahead of the front...which will be the
source for low level moisture/instability for the front to work
with.  Not a lot of moisture in a relative sense (dry above 700mb)
so raises some questions as to precipitation coverage being limited
by dry air entrainment into updrafts that probably won`t be all that
robust to begin with (there may be some low clouds (high based Sc)
at the start of the day to inhibit heating/destabilization). Overall
a light precipitation event at best at this point...minimal
probabilities for rainfall exceeding 0.25 inch during the day
Saturday.  Rain chances expected to wind down from west to east by
Saturday evening.

Cooler with some small rain chances Sunday: Will be watching a short
wave trough dig into the Lake Superior basin Sunday along with an
associated jet streak.  Can`t rule out a few light showers as this
feature passes through mainly Sunday afternoon/evening but this also
looks pretty minimal.  After highs into the 70s and possibly some
lower 80s Saturday...cold advection in the wake of Saturday`s
frontal passage expected to drops highs down into the 60s (lower 70s
in downslope areas adjacent to Saginaw Bay).

More substantial rain event arrives Monday night/Tuesday; heavy
rainfall potential: Monday itself is expected to be dry as a
short wave ridge and surface high pressure cross the Great
Lakes. In the wake of this ridging deep layer southwest flow
develops Monday night...with a strong low level jet ahead of a
cold front that will make slow inroads into the upper Lakes as
it parallels the flow aloft. Thermal/moisture advection ahead of
this front expected to bring rain and some embedded
thunderstorms back into northern Michigan Monday night and into
Tuesday...though may see a drying trend Tuesday afternoon
especially the farther north you go. Given the deep layer
unidirectional flow QPF potential will be much greater than
anything that falls this weekend: 1 inch/24h rainfall
probabilities (ending 0000Z Wednesday exceed 50 percent north of
the M-72 corridor...with probabilities around 25 percent of
exceeding 2 inches/24 hours across eastern Upper. Thus the
slight Excessive Rainfall Risk across Upper Michigan for Monday
night. Things to watch for beyond Tuesday will be how far front
the cold front can sink...if it lingers closer to the US-10
corridor will be facing a more substantial heavy rain threat
across the southern portion of the forecast area.

&&

.AVIATION /00Z TAFS THROUGH 00Z SUNDAY/...
Issued at 1144 PM EDT Fri Sep 11 2026

Band of showers (perhaps maybe a TSRA) will cross the area from
midday thru the afternoon. Best chance for rain will be at
CIU/PLN. Cigs/vsbys might approach MVFR, again especially at
CIU/PLN, but for now will keep things barely VFR. Otherwise
VFR. Sw winds become breezy Saturday, veering northwest late,
and lightening in the evening.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement from 8 AM EDT Saturday through
     Saturday evening for MIZ025-031-096-098.
     Beach Hazards Statement through Saturday evening for MIZ095.
MARINE...Small Craft Advisory from noon to 8 PM EDT Saturday for
     LHZ345>347.
     Small Craft Advisory from 8 AM to 8 PM EDT Saturday for LMZ323-
     342-344>346.
     Small Craft Advisory until 8 PM EDT Saturday for LMZ341.

&&

$$

DISCUSSION...JPB
AVIATION...JZ