350
FXUS63 KMQT 251910
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
310 PM EDT Wed Sep 25 2024

.KEY MESSAGES...

- Dry weather is expected into the weekend.

- Temperatures trend well above normal into next week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 307 PM EDT Wed Sep 25 2024

As low pressure has lifted into Ontario this morning, GOES-16 Day
Cloud Phase RGB imagery just shows some fair weather cu across the
central UP with a few low clouds over the Keweenaw. The RAP analyzes
a 1016 mb high centered over eastern Kansas that extends pressure of
at least 1011mb all the way from western Upper Michigan to the Rio
Grande Valley, and this broad high pressure will keep the weather
quiet through tonight. Temperatures have already reached into the
70s in some areas of the UP which is about what the high is expected
to be today.

Overnight, the warming trend in low temperatures continues with the
lowest of lows expected in the interior west around 45 degrees, with
lows up to the low 50s expected elsewhere. The main forecast
question revolves around whether or not fog will be able to form.
Blending hi-res model wind gives surface winds overnight around 5
knots, which is a bit high for radiation fog formation even with RHs
of 100% expected by the early morning hours. HREF chances of
visibility falling below 1 mile overnight are 0 for the west half
but range from 20-50% in the east half. GLAMP and Euro probabilities
of fog vary significantly by location, from 0-10% in the far west to
up to 40% in the central-to-east. Ended up going patchy fog tonight
(20%) given the uncertainty.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 224 PM EDT Wed Sep 25 2024

Upper air pattern consists of a 500 mb closed low of Hurricane
Helene in the Gulf of Mexico, a closed low over the mid Mississippi
Valley, and a closed low over southwest Quebec with a trough in the
Pacific NW and a ridge in the southern Rockies into the northern
Plains 12z Thu. The ridge builds into the upper Great Lakes Thu
night through Sat and will bring dry and warm weather to the area.

In the extended, the GFS and ECMWF show a 500 mb closed low over the
Ohio and Tennessee Valleys 12z Sunday with a trough in the Pacific
NW and ridging over the southern and central Rockies into the upper
Great Lakes. Troughing moves into the northern plains 12z Mon and
into the upper Great Lakes 12z Tue as a ridge builds into the
western U.S. Ridging moves into the southern half of the U.S. 12z
Wed. Temperatures start out above normal for Sunday and Monday and
then drop to near normal for Tuesday and Wednesday as colder air
moves in.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 132 PM EDT Wed Sep 25 2024

With low pressure well to the east and departing the region to the
northeast, fair weather and VFR will prevail today. Winds mainly out
of the northwest around 5 to 10 kt will become light and variable
tonight. Fog remains about 20% likely at IWD and CMX, though
probabilities are increasing slightly at CMX. With some higher
probabilities up to 35% at SAW overnight, a TEMPO group has been
added for MVFR fog. If guidance continues to suggest increasing
probabilities of fog, MVFR or lower visbys may become the prevailing
condition for tomorrow morning in future TAF issuances.

&&

.MARINE...
Issued at 224 PM EDT Wed Sep 25 2024

Upper Michigan will remain under high pressure for the duration
of the forecast period. Therefore, winds will remain at or below 20
knots through Sunday. 20 to 30 knot winds will not be until Monday
when the next system starts to enter the region.

&&

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

&&

$$

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