058
FXUS63 KMQT 230423
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
1123 PM EST Sat Feb 22 2025

.KEY MESSAGES...

- Widespread light wintry mix anticipated ahead of a clipper
  system Sunday night into Monday. Rain and snow are expected
  with a 15% chance of a light glaze of freezing rain prior to
  the Monday morning commute.

- Warmer than normal temperatures through the first half of
  next week with highs likely above freezing. A colder pattern
  possibly shapes up into next weekend.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 249 PM EST Sat Feb 22 2025

Water vapor imagery and RAP analysis show nw mid-level flow into the
Great Lakes this aftn. A couple of shortwaves embedded in this flow
have produced some areas of -sn across Upper MI today, mainly across
western and northern Upper MI. Current temps range thru the 20s to
the lwr 30s F.

Shortwave currently nw of Lake Superior will pass across the area
this evening. Until passage, some areas of -sn/flurries will
continue. Last of the -sn is about to depart the Keweenaw, and it
will exit the eastern fcst by midnight, if not sooner. Sfc trof
dropping s across Lake Superior tonight will end up over southern
Lake Superior or just into northern Upper MI. Might be some flurries
associated with it, but since air mass is not cold enough to support
lake effect shsn, did not include any mention of pcpn with the trof.
Expect min temps mostly in the upper teens to mid 20s F, but
traditional interior cold spots may slip to the lower teens F.

&&

.LONG TERM /SUNDAY THROUGH SATURDAY/...
Issued at 421 PM EST Sat Feb 22 2025

Outside a few morning flurries, dry weather is anticipated on Sunday
as light winds become S by the afternoon and gradually increase
through the day. With WAA, some above normal highs are anticipated
in the 30s to low 40s with most warming at least to freezing. This
also helps gusts in S downslope areas approach 20 mph by Sunday
evening...gusts up to 20-30 mph are possible (50% chance) Sunday
night into Monday as a 35-45 kt LLJ passes overhead.

A shortwave and approaches from the NW Sunday night, sending clipper
low over far N Ontario Sunday night through Monday. WAA ahead of it
increases cloud cover from the W Sunday afternoon and supports light
precip Sunday night into Monday. Model soundings leave little
confidence in p-type as profiles do show a warm nose between
900-850mb, but there is a wide range of solutions regarding
p-types and timing of them. Favored the NBM p-type solution
given the low confidence, but a wintry mix of rain and snow is
expected. The 2/22 12Z HREF indicates between a 20-50% chance
for up to 0.01" of ice from freezing rain ahead of the Monday
morning commute, but the NBM probs are lower around 10-20%.
While the NAM/NAM Nest/GFS deterministic solutions place up to
0.03-0.06" over parts of the north-central and east, the
HRRR/RAP solutions of just a light glaze are the more likely
solution as the inversion is not particularly noteworthy.
Otherwise snow accumulations should be limited to a few
hundreths on the high end in Keweenaw, Alger, Schoolcraft, and
Luce counties. This wintry mix combination could impact the
morning commute on Monday. Will need to continue to monitor this
risk as it approaches; future forecast packages could include
an SPS for potential slippery road conditions. Highs on Monday
are expected in the upper 30s to mid 40s, but could push near
50F if MOS guidance is correct.

Trailing rain/snow chances (15-25%) continue Monday into Tuesday as
the shortwave moves overhead. Another shortwave travels quickly
behind it, sending the lingering sfc trough S. With limited moisture
and unimpressive forcing, impacts are not expected as QPF struggles
to reach 0.01"/6hr. The remainder of the forecast suggests the NW
flow sends additional shortwaves over the area with associated
clipper systems. Spread on sfc track/timing in the ensemble guidance
remains so the NBM solution was left as is Tuesday night onward. The
two periods of higher PoPs are Wednesday and then Friday into
Saturday. With the warmer airmass still in place on Wednesday highs
will be in the 30s to low 40s with lows in the 20s. This keeps rain
chances in the mix on Wednesday, but chances for rain diminish into
next weekend as potentially a colder airmass settles in. The GFS
currently is the colder solution, leaning toward mainly snow for the
system into next weekend while the ECMWF remains more mild. There is
better consensus for cooler temps late next weekend into the
following week which could bring LES back to the UP on Sunday.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 1123 PM EST Sat Feb 22 2025

Expect VFR to prevail at all terminals through the period.

&&

.MARINE...
Issued at 421 PM EST Sat Feb 22 2025

W to WSW winds of 15-25 kts this afternoon gradually settle below 20
kts this evening, becoming light and variable tonight into Sunday
morning. Winds then become S, increasing to 20-30 kts over the E
half and 15-25 kts over the W half ahead of a clipper low passing
over N Ontario. Winds over the W half increase to 20-30 kts by
Monday morning as winds across the lake veer W for the remainder of
the day. There is a 10-30% chance for gale force gusts to 35 kts
late Sunday night into Monday. Waves are expected to peak around 6-8
ft N and NE of the tip of the Keweenaw Peninsula on Monday. W winds
settle to 15-25 kts by Monday evening, falling below 20 kts by
around midnight Monday night. Winds then remain near or below 20 kts
for much of the week with uncertainty regarding the path of any
potential clipper lows through next week. Should a low pass directly
over the lake, gale potential would increase to 20-40%, but there is
much uncertainty regarding timing any low pressure passages at this
time.

&&

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

&&

$$

SHORT TERM...Rolfson
LONG TERM...Jablonski
AVIATION...07
MARINE...Jablonski