929
FXUS63 KAPX 010334
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
1134 PM EDT Wed Sep 30 2026

.KEY MESSAGES...

- Areas of fog tonight into early Thursday morning

- Times of light to moderate rain early Thursday morning will
  last through Thursday afternoon, less rain for eastern upper

- Brief chances for light rain this weekend, with a general
  trend of cooler temperatures into next week

- Frost potential early Saturday morning, better chances for
  widespread frost early next week

&&

.DISCUSSION...
Issued at 301 PM EDT Wed Sep 30 2026

The first wave of precipitation is moving through northern MI today,
dropping around a quarter to just under an inch in areas adjacent to
Grand Traverse Bay so far. Lower amounts east of I-75, with only a
couple hundredths near Saginaw Bay. Deep moisture is present, with
the 12z KAPX RAOB showing a near daily max 1.49 inch PWAT value.
Warm rain processes are in action, as the WCD was over 11 kft.
Forcing has remained more moderate, keeping rainfall light to
moderate at times, and resulting in totals remaining under an inch.
This wet airmass will continue overnight and into Thursday as an
upper closed low in the desert SW lifts north into the central
plains and continues to direct the plume of deep tropical
moisture towards the Great Lakes region. At the same time, a
larger surface cyclone will continue to track eastward over
central CAN. An upper shortwave will help reinforce the
southward progression of the cold front Thursday. Above our
heads, upper ridging over the SE CONUS will be present
Thursday, as well as broad upper troughing over CAN. These join
near the Great Lakes region Thursday, placing northern MI in the
right entrance region right behind the cold frontal passage,
which will be the afternoon and evening of Thursday. Ahead of
the front, a 30 - 40 kt LLJ will stretch from MO through
southern MI. This will likely remain south of M-55, as the
frontal boundary will meet with it late morning Thursday. The
front near the surface will track across northern MI in the
afternoon hours.

All of this is to say that the timing and positioning of forcing
doesn`t quiet align for repeated rounds of widespread heavy
rain, or even thunderstorms. Areas of fog will be seen tonight
into early Thursday morning as the deep tropical moisture
continues. Widespread light to moderate rain will be seen with
that secondary surge of deep moisture early Thursday morning,
adding another quarter to a half inch of rain over northern
lower with less over eastern upper. Times of light to moderate
rain will continue over northern lower into the morning hours as
the boundary aloft moves overhead and meets the LLJ to our
south (keeping it south). Midday to the early afternoon hours,
isolated heavy rain for spots in northern lower will be possible
where the larger scale forcing meets with the lower level
forcing. There is also less than 100 j/kg of instability near
the surface as drier air starts to work its way in and some
peaks of sunshine could warm the surface up enough. This
instability is capped in the mid levels, so it would help
produce isolated moderate/heavier rain but not much more. Most
rain will exit by Thursday evening, with clouds and breezy
northwest winds. Winds will diminish over interior spots with
partly cloudy skies into Friday morning. Breezy northwest winds
will continue around coastal areas.

The surge of cooler air aloft will occur Friday, and could generate
some light lake effect rain showers over eastern upper and along and
north of M-72. This will likely hold in some moisture near the
surface for Friday night into Saturday morning, when the center of a
1025 mb surface high moves directly overhead. Guidance is split on
if temperatures will reach freezing or not, as fog and even freezing
fog remains possible into early Saturday morning. Lake surface
temperatures in the 50s and 60s remain too warm for freezing
temperatures along coastal communities.

A quick hitting weak system will track over CAN and bring brief rain
chances to eastern upper and near the tip of the mitt late Saturday
into Sunday. A cooler CAN airmass will slide over the Great Lakes
early next week, with increasing confidence for freezing temps early
Tuesday morning (greater than 60% chance for most interior northern
lower to dip at or below 32F).

&&

.AVIATION /00Z TAFS THROUGH 00Z FRIDAY/...
Issued at 1134 PM EDT Wed Sep 30 2026

Occasional -DZ occurring at some sites this evening. Otherwise
cigs/vsbys should slowly worsen tonight, with IFR/LIFR becoming
more widespread overnight, just ahead of our next area of rain.
Showers are expected at the northern lower MI TAF sites
Thursday, especially MBL/APN (MBL should see the heaviest
rain). Cigs/vsbys do start to improve by late morning.

Light s to sw winds tonight and Thu morning, veering nw and
increasing late Thursday.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until midnight EDT tonight for LHZ348-349.
     Small Craft Advisory until 5 AM EDT Thursday for LMZ323-341-
     342-344>346.

&&

$$

DISCUSSION...ELD
AVIATION...JZ