Copemish, Michigan Weather Forecast Discussion

591
FXUS63 KAPX 202329
AFDAPX
Area Forecast Discussion
National Weather Service Gaylord MI
729 PM EDT Sat Sep 20 2025
.KEY MESSAGES...
- Scattered showers and storms at times through the weekend.
- Marginal Risk for severe storms Sunday.
- Shower chances continue at times Monday through much of the week
  with near to slightly above normal temperatures.
&&
.SHORT TERM /THROUGH SUNDAY/...
Issued at 200 PM EDT Sat Sep 20 2025
Pattern Synopsis/Forecast: Upstream trough axis is situated from the
Canadian Prairies southeastward into the TN Valley this afternoon.
Center of associated surface reflection sits over northwest MN with
a nearly stationary warm front draped to our west/southwest. LLJ
ramps up tonight with moisture advection expected as that warm front
lifts northward, eventually shifting north of the forecast area
later Sunday afternoon. Combined with increasing upper-level support
and continued shower/storm chances will be the rule through the
remainder of the weekend.
Forecast Details: Some showers and a rumble of thunder linger this
afternoon, primarily across parts of northwest lower and the
eastern U.P. Additional, more numerous, showers and embedded
storm are expected to arrive across western areas this evening
with those chances spreading east overnight. Given increasing
ample moisture this evening with PWs progged as high as 1.4"
west of I-75 and potentially some pockets of instability,
locally heavy downpours are the main concern through tonight (as
has already been the case so far today with localized radar
estimated rainfall of 2-5" across parts of western Antrim
County).
For Sunday, expecting shortwave energy, on the southeast periphery
of incoming parent trough axis, to trek across northern MI Sunday
into Sunday night. Expecting another round of showers/storms during
the day into Sunday night, depending on timing of this wave. Latest
trends support the focus for this to be across north-central and
northeast lower -- coinciding with the area that SPC has outlooked
for a Marginal Risk for severe storms on Sunday. Combination of
potentially a few hundred J/kg of instability and deep layer shear
on the order of 25-30 knots may support that low end threat --
albeit latest hi-res guidance trends are far from impressive with
this notion. High temperatures expected to be in the upper 60s far
north and from the low-mid 70s across much of northern lower. Few
points creeping into the low-mid 60s yielding a more muggy feel.
&&
.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
Issued at 200 PM EDT Sat Sep 20 2025
Pattern Forecast: Some semblance of upper-level troughing is
expected to continue across the nation`s midsection through the vast
majority of the long-term forecast period. Initial system crossing
the area this weekend largely departs Monday with a weak cold front
crossing during the day. Beyond that, waves of additional mid-upper
level energy combined with diurnal processes may continue
shower/storm chances at times through at least midweek onward. The
envelope of solutions widens late week -- largely hinging on
evolution of the upper air pattern/interaction between upper ridging
building across Ontario and potential cutoff upper low over the mid-
MS and OH valleys.
Forecast Details: Shower and storm potential continues Sunday night
with a continued low-end strong storm threat into the evening hours.
Locally heavy downpours still a good bet, however, with PWs progged
nearly 2 SD above the mid-late September climatological mean.
Combination of continued upper-level energy overhead Monday, cold
front progressing across the forecast area and lingering
instability/moisture should yield a continued shower/storm threat
for parts of Monday and Monday night. Similar story for Tuesday with
lingering precipitation chances as energy pinwheeling overhead
combines with diurnally driven instability to potentially produce
some additional showers/storms, most numerously during the
afternoon/early evening hours.
Less confidence prevails midweek onward, largely hinging on the
evolution of the upper air pattern. By and large, two differing
solutions exist within the latest suite of deterministic guidance.
One that pulls upper-level low pressure northward from the mid-MS
and Ohio valleys resulting in widespread precipitation chances late
in the week. Opposing solution keeps that upper-low suppressed well
to the south with primarily dry weather locally. Majority of
ensemble members/means favoring the latter of those two solutions
and continue with that trend in the forecast.
&&
.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 729 PM EDT Sat Sep 20 2025
Showers and a few storms become increasingly likely tonight and
Sunday. Brief vsby restrictions are likely at some point, but
VFR will be the most prevailing condition thru the TAF period.
Some MVFR cigs are possible on Sunday, best chance at CIU. Se
breezes continue.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement until 4 AM EDT Sunday for MIZ017-018-
     088-096-097.
MARINE...Small Craft Advisory until 4 AM EDT Sunday for LHZ345>348.
     Small Craft Advisory until 4 AM EDT Sunday for LMZ341-342.
     Small Craft Advisory until 4 AM EDT Sunday for LSZ322.
     Small Craft Advisory until 11 AM EDT Sunday for LSZ321.
&&
$$
SHORT TERM...MJG
LONG TERM...MJG
AVIATION...JZ

NWS APX Office Area Forecast Discussion