671
FXUS63 KMQT 291831
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
231 PM EDT Wed May 29 2024

.KEY MESSAGES...

- Widespread frost expected tonight across much of the UP away
  from the shores of the Great Lakes. Localized hard freezes
  cannot be ruled out but is not expected to be widespread.

- Below normal temperatures through tonight, then warming up
  through early next week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 230 PM EDT Wed May 29 2024

GOES Visible imagery shows a near-perfectly clear sky over the
UP today with fair weather cu staying to the south and west of
the UP. This is caused by a RAP-analyzed 1025mb high pressure
centered over west-central Lake Superior this afternoon,
supported by ridging aloft over the Great Plains. High temps
this afternoon in response to the clear skies will climb into
the 60s for much of the interior UP, though lingering northerly
wind gusts will keep the Lake Superior shores in the 50s.

Overnight, clear skies will continue. With a well-mixed airmass that
has already seen RHs falling into the 20s, radiational cooling is
expected to be quite efficient. However, various rules of thumb
point to temperatures only reaching around freezing or just above
freezing, with MOS guidance trending warmer with recent model runs.
Forecast lows overnight are now forecast to be as low as 30F as a
result, though it would not be a surprise for the typical cold spots
in valleys and other low-lying areas to have hard freezes. While
hard freezes will be limited to localized areas, frost should be
widespread in the early morning areas for all of the UP away from
the shores of the Great Lakes.

&&

.LONG TERM /TONIGHT THROUGH TUESDAY/...
Issued at 250 AM EDT Wed May 29 2024

Upper air pattern consists of a 500 mb trough in the ern U.S., a
trough in the western U.S. and a ridge in the upper Mississippi
Valley 00z Thu. This ridge moves into the upper Great Lakes 00z Fri
with the trough moving into the northern plains. This trough moves
into the upper Great Lakes 00z Sat. Frost still looks likely
tonight, but below freezing temperatures look to be brief. Still not
confident enough though to get with a frost advisory though as most
guidance is warmer even though ideal radiational cooling with light
winds and a clear sky sets up tonight. Otherwise, did not make too
many changes to the going forecast.

In the extended, the GFS and ECMWF show a 500 mb trough on the west
coast, a trough in the upper Mississippi River Valley and a ridge in
the ern U.S. 12z Sat. The western trough moves into the Rockies 12z
Sun and into the northern plains 12z Mon and into Ontario 12z Tue.
Another trough moves into the Rockies 12z Tue and into the northern
plains 12z Wed. Temperatures remain above normal for this forecast
with a sfc front hanging around the area which could kick off some
convection at times. Only real dry period looks to be Sat night into
Sunday.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 125 PM EDT Wed May 29 2024

Under high pressure, VFR will prevail at all TAF sites with SKC
conditions and P6SM vis through 12Z Thursday. Winds may be
variable, but they will be mainly 5 knots or below through the
TAF period with the exception of gusty conditions currently at
SAW and IWD.

&&

.MARINE...
Issued at 250 AM EDT Wed May 29 2024

High pressure over the Great Lakes and with no strong systems
passing by or through, the wind stays at or below 20 knots through
the 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