825
FXUS63 KMQT 241922
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
322 PM EDT Tue Sep 24 2024

.KEY MESSAGES...

- Around 20% chances of patchy fog tonight with a slight chance
  (~10%) of some dense fog.

- Dry weather is expected this week into the weekend.

- Temperatures trend to well above normal into next week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 322 PM EDT Tue Sep 24 2024

GOES-16 Day Cloud Phase RGB imagery shows fair-weather cu across
much of central and western Upper Michigan. Meanwhile, further
south, a RAP-analyzed 1007mb low is churning over southern Lower
Michigan as it moves northeast. This low will mainly miss the UP to
the south and east, but there remains a 20-30% chance of a few
isolated light rain showers over Luce County this evening and slight
chances (~15% for western Schoolcraft and Alger counties to get some
rain as well. Expect highs to only top out in the mid 60s to low 70s
today, which is around normal for this time of year.

These showers should depart slowly through the overnight period and
the extra cloud cover should help keep low temperatures tonight from
tanking too low with bias-corrected MOS guidance suggesting lows in
the 40s in the west and low 50s in the east. GFS LAMP guidance
suggests another night of patchy fog is possible with probabilities
of visibility below 5 miles of around 30% and below one mile
visibility at around 10%. The HREF is a bit more aggressive with fog
formation tonight with widespread probabilities of 1 miles or less
visibility around 30-60%. Euro visibility meteograms line up well
with the GFS LAMP guidance, so will lean that way with patchy fog
probs around ~20%.

&&

.LONG TERM /THURSDAY THROUGH MONDAY/...
Issued at 232 PM EDT Tue Sep 24 2024

Upper air pattern consists of a 500 mb trough on the west coast, a
ridge in the Rockies and a trough in the Mississippi Valley and
Great Lakes region 12z Wed. Ridging then moves into the northern
plains by 00z Thu and builds into the upper Great Lakes after 00z
Fri. Dry weather continues through Friday.

In the extended, the GFS and ECMWF show a 500 mb closed low over the
mid Mississippi Valley with a ridge over most of the rest of the
U.S. 12z Sat which remains the same through 12z Sun. By 12z Mon, a
trough moves into the northern plains which then moves into the
upper Great Lakes 12z Tue. Temperatures look to be above normal
through the period with a cooling trend on Tuesday. Went dry for
pops Sat night through Sun night with high pressure in the area.
Starting Monday, pops start to show up in the forecast, but thinking
is they might be overdone a tad bit especially with upper level
ridging in the area which is strong. Only fly in the ointment is a
sfc cold front stalled out over the area Monday which looks to start
off dry anyway before upper troughing starts to affect the area
Tuesday. Confidence is low with pops on Monday and would like to
trim back pops on Tuesday as they seem overdone due to strength of
upper ridge, but will leave alone for now as manual progs show a
cold front moving through the area.

&&

.AVIATION /18Z TAFS THROUGH 18Z WEDNESDAY/...
Issued at 140 PM EDT Tue Sep 24 2024

Aside from a pesky MVFR deck at KCMX that is only expected to hang
on another couple of hours into the afternoon at most, VFR prevails
at all TAF sites through this evening. Mainly light winds under 5
knots with low pressure well to the southeast, though the direction
may become variable especially in the vicinity of lake breezes.
Overnight, CMX and IWD will stay VFR, but SAW is at least 35% likely
to see radiation fog drop visbys below MVFR thresholds with up to
15% probabilities of airport minimum dense fog. For now, will cap at
MVFR, but if model trends towards lower visibility, could see IFR or
LIFR in future TAF issuances.

&&

.MARINE...
Issued at 232 PM EDT Tue Sep 24 2024

With a persistent benign pattern over the area, the wind will stay
at or below 20 knots for this forecast period.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.

&&

$$

SHORT TERM...GS
LONG TERM...07
AVIATION...GS
MARINE...07