326
FXUS63 KAPX 181710
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
110 PM EDT Mon Aug 18 2025

.KEY MESSAGES...

- Showers and a few embedded thunderstorms tonight into
  Tuesday...with some pockets of heavier rain expected.

- Dry with seasonable temperatures through the remainder of the work
  week.

- Perhaps more showers Friday night into Saturday.

- Potentially turning sharply cooler Sunday.

&&

.SHORT TERM /THROUGH TUESDAY/...
Issued at 1259 PM EDT Mon Aug 18 2025

Pattern Synopsis/Forecast:

All attention directed at approaching shortwave trough and attendant
surge of deep layer moisture advection. Areas of showers and
embedded thunderstorms tied to these above features centered
especially across Wisconsin early this afternoon. Leading edge of
this deeper moisture working into our area, manifested mainly by
some increasing clouds across most of the area...with leading warm
air advection wing of showers spreading into our southwest zones.
Otherwise, another day of rather pleasant temperatures, with
expected highs this afternoon topping out mostly in the 70s.

Upstream wave will work steadily east through the area tonight into
early Tuesday, bringing with it pretty decent prospects for some now
much needed rainfall. High pressure begins to exert its influence
later Tuesday...setting the stage for a rather pleasant remainder of
the work week.

Primary Forecast Concerns:

Main focus on shower and thunderstorm evolution/timing tonight and
Tuesday.

Details:

Respectable set-up unfolds tonight for some rather widespread rains,
with arrival of that wave helping drive precipitable water values up
and over 1.75 inches...with near saturation through the vertical.
While forcing is not overly impressive within this moisture rich
environment...mass convergence on nose of developing weak low level
jet and simple breadth of moisture advection should theoretically
support continued shower development and organization of those
showers as they spread northeast into the area later today into the
overnight. While a few embedded thunderstorms are expected, definite
lack of instability and weak mid level lapse rates looks to negate
any severe weather concerns. However, as mentioned yesterday, those
same weak mid level lapse rates supports the classic heavy rain
producing "skinny" cape profiles...with that limited cape centered
in a completely saturated mid-level environment. Decent warm cloud
depth (up and over 14kft) also supports some heavier rain
rates...well in excess of an inch per hour with any deeper
convection. Showers should remain transient, so not expecting any
flooding concerns (perhaps road ponding in poor drainage
areas)...but could see local areas receive up and over an inch of
rain by sunrise Tuesday.

Most organized area of showers expected to exit stage right during
Tuesday morning, leaving behind just some much more scattered and
lighter activity in the afternoon. Clouds and lingering showers
should keep high temperatures in the 70s.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
Issued at 1259 PM EDT Mon Aug 18 2025

Pattern Synopsis/Forecast:

Large area of slow moving high pressure set to dominate our weather
through much of the remainder of the week. Almost the entirety of
the mid-range guidance ensemble suite shows pattern retrogression
taking place next weekend...with stout upper level ridge building
across the Intermountain West and subsequent trough digging into
northeast NOAM and the Great Lakes.

Primary Forecast Concerns:

Temperature trends and addressing rain potential as that weekend
pattern change takes shape.

Details:

Just downright pleasant conditions expected Wednesday through Friday
as that high pressure slowly works across the northern Great Lakes.
Gradual warming trend through the period, with highs in the 70s
Wednesday warming to widespread 80s by Friday. Set-up favors some
cool overnight conditions both Wednesday night and Thursday
night...with clear skies, light winds, and a dry airmass. Could
easily see some of our traditional interior colder locations make a
run into the 40s both of those nights.

Pattern amplification mentioned above should drive a cold front
southeast across the area sometime later Friday into Saturday.
Current trends support a complete disconnect to any sub-tropical
moisture contribution ahead of this front...supporting limited
chances for any real organized rainfall. Bigger story will be a
downward slide with temperatures. If current trends do indeed hold,
we could be looking a some areas not getting out of the 60s by
Sunday. We shall see.

&&

.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 111 PM EDT Mon Aug 18 2025

Clouds continue to increase, along with shower chances as we
progress into this evening. As such, VFR CIGs prevalent this
afternoon will gradually decrease to MVFR from west to east with
time this evening into tonight. CIGs may fall to IFR if any embedded
TSRA / downpours can materialize and move over TAF sites (best
chances favor MBL, TVC, and APN). Otherwise, RA tapers into
Tuesday morning, with some lingering MVFR CIGs in its wake.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement until 9 PM EDT this evening for MIZ017-
     018.
MARINE...Small Craft Advisory until 4 AM EDT Tuesday for LHZ345>347.
     Small Craft Advisory until 2 PM EDT this afternoon for LHZ348-
     349.
     Small Craft Advisory until 2 AM EDT Tuesday for LMZ341-342.
     Small Craft Advisory from 6 PM this evening to 2 AM EDT
     Tuesday for LSZ321.

&&

$$

SHORT TERM...MSB
LONG TERM...MSB
AVIATION...HAD