752
FXUS63 KAPX 061044
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
644 AM EDT Sun Jul 6 2025

.KEY MESSAGES...

- Scattered thunderstorms today with locally heavy rainfall possible.

- Generally quieter and cooler weather to start the work week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 412 AM EDT Sun Jul 6 2025

Potent lobe of PV swinging across central Canada with strong height
falls (-8dm/3hrs) near James Bay as of last evening with cooler and
drier air sinking into central Canada. Southern end of its influence
is smooshing along the peak of the ridge axis still trying to hang
onto the Upper Great Lakes...resulting in northerly low-level flow
into WI and Lake Superior behind a surface boundary/cold front
stretching from eastern Lake Superior back into central/SW WI. Plume
of 2+in pwats stretches along this boundary back to its source over
TX...with surface high pressure still holding onto the southeastern
US despite a tropical disturbance hanging out off the Carolinas.
Area of rain showers moving SW-NE up our slow-moving boundary, with
most of the rain dumping upstream (though AWOS on Beaver Island
picked up 1.17in between 0z and 6z closer to more convective foci
for activity (e.g. mesolow, gravity waves, etc)); rain has (somewhat
as usual) not held together as well over our mainland areas thus
far.

Expecting the cold front to slowly sink into the region from N to S
today...likely reaching Saginaw Bay by late afternoon. Expect
showers and some storms will continue through the day today,
especially along/ahead of the cold front, where heaviest rainfall
totals should occur...though think there could be some post-frontal
rain as well to keep things on the dreary side into the evening.
Much cooler today north of the front beneath lingering
clouds/rain...with temps not likely to move much from current status
in the upper 60s to lower 70s...and could fall through the
afternoon, accompanied by decreasing humidity. NE Lower should get a
better shot at warming up again today...with highs reaching into the
upper 70s to lower 80s. Lows tonight should be much more comfortable
overall, with most areas dropping into the 50s. (Not impossible some
fog could try to develop tonight where more appreciable rainfall is
had today...but will depend on how well we dry out today.)

Primary Forecast Concerns through Tonight:

Storm potential through this afternoon and heavy rainfall concerns...

Think there will be some convection and heavy rain potential
attendant to the surface cold front this morning into this
afternoon, particularly across NE Lower, especially toward Saginaw
Bay (as usual). Best chance for thunder will also be here, where as
much as 1-2k J/kg MUCape are possible in a potentially uncapped
environment if we warm enough. Deep layer shear looks rather meager
still, and not expecting any severe weather with this, though a
stronger storm can`t be ruled out near the Lake Huron coast this
afternoon. Some signals for a bit of dry air to sneak into the mid-
levels could suggest the possibility for enhanced downward momentum
and perhaps gusty winds...though not much wind aloft today to drag
down.

Also think a more synoptic-type rain could develop behind the
primary line across NW Lower/Tip of the Mitt this afternoon into
this evening, along the 700mb trough axis on the northern edge of
the moisture shield (where pwats may still be in the 1.5-2in range
ahead of a tight moisture gradient), which will be slow to depart as
next bits of energy slip by to our north. If some sort of narrow
deformation band develops...not impossible a narrow swath of locally
heavy rain occurs...though forcing aloft may be limited with this
feature.

For what it`s worth...hi-res prob guidance does have some
signals (approx 30 percent) for an inch of rain in 6hrs across
localized part(s) of NW Lower Sunday morning/afternoon...though NE
Lower has a more widespread shot at an inch of rain (or more) within
the more convective rainfall (40-60 percent chance, generally south
of a line from Alpena to Clare, with some higher chances popping up
over Arenac county/Rifle River basin and perhaps southeastern
Gladwin county)...where skinny cape and high freezing levels support
more efficient warm rain processes amid that still very moist
airmass...though aforementioned potential for some mid-level dry air
to sneak in could ruin this better rainfall potential for us
(again).

&&

.LONG TERM /MONDAY THROUGH SATURDAY/...
Issued at 412 AM EDT Sun Jul 6 2025

Days 2-3 (Monday-Tuesday)... Largely zonal flow aloft with lingering
surface high pressure to keep things quiet and seasonable for the
day Monday. Another bit of PV tries to zip across the northern
portions of the Upper Midwest...but signals currently point to this
shearing out as it reaches us...and we may end up with little in the
way of activity at all until later Tuesday/Tuesday
night/Wednesday(?)...as another niblet of energy looks to dig into
the Upper Great Lakes.

Days 4-5 (Wednesday-Thursday)...Upstream ridging building through
the western/central US suggests northwest flow and most likely high
pressure for us. Setup across the central conus may again be
favorable for activity to run along the perimeter of the ridge,
possibly into the Upper Midwest at some point from the latter half
of the week onward...perhaps as early as Wednesday/Thursday, as
guidance points toward a more potent disturbance out west tilting
the ridge axis back our way again. Attm, though...think the core of
the ridge axis will be too far to our west/southwest through midweek
for activity to reach northern Michigan.

Days 6-7 Outlook (Friday-Saturday)...Aforementioned signals for
ridging to try to tilt into the region could suggest a period of
warmer, and perhaps unsettled, weather for the latter half of the
week into the weekend. Quite a bit of uncertainty remains in how
this evolves, though...as lingering disturbances from midweek could
try to slow the flow across the central US...especially if the core
of the ridge axis and its attendant activity remains closer to the
Desert SW.

&&

.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 644 AM EDT Sun Jul 6 2025

Numerous showers this morning. These will start to diminish in
the west this afternoon as a cold front goes thru. But showers
will linger at APN into late afternoon or early evening. APN
also has the best chance of seeing TSRA later today, though have
not included in the going TAF. IFR cigs will continue to become
commonplace this morning, with improvement this afternoon and
evening (APN taking longest).

A sw breeze veers nnw to n by late today.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.

&&

$$

SHORT TERM...FEF
LONG TERM...FEF
AVIATION...JZ