466
FXUS63 KMQT 070718
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
218 AM EST Thu Nov 7 2024

.KEY MESSAGES...

- Westerly winds turn gusty this afternoon through tonight, with
gusts in excess of 40mph across the Keweenaw and higher gusts to
50mph possible (50% chance).

- A Wind Advisory is in effect for the Keweenaw beginning this
  evening.

-Dry weather weather today through the end of the week with
temperatures above normal, then rain returns Saturday night and
Sunday.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 218 AM EST Thu Nov 7 2024

Surface ridging is extending into the Great Lakes with sprawling
high pressure over the Plains, while aloft, a midlevel shortwave is
dropping through Ontario. With a dry airmass in place, this
shouldn`t result in any precipitation over the area - perhaps just
some stray mid and upper level cloud cover scraping the area. Some
patchy low stratus is also apparent across the UP and northern WI on
satellite, but skies for the most part remain clear. This is helping
temperatures drop back into the 30s across most of the UP, and into
the upper 20s in the interior -central and -west.

Skies stay sunny today, with temperatures yet again coming in
slightly above average. Expect highs in the upper 40s to lower 50s.
Meanwhile, westerly winds will be on the increase this afternoon as
deepening low pressure moves south of Hudson Bay, reaching James Bay
by the evening and setting up a tight pressure gradient over the
Great Lakes. A 40-50kt LLJ moves over the UP and Lake Superior this
evening, when inversion heights will still be up to ~2kft and lower
level lapse rates look steep enough to mix down some good gusts. The
strongest look to be across the Keweenaw, with gusts in excess of
40mph common for a brief period tonight and some stronger gusts to
50mph possible. A Wind Advisory has been issued for the Keweenaw
this evening into the first half of the night. Expect mostly clear
skies overnight with temperatures once again falling into the 30s,
possibly into the upper 20s in the typically cooler interior spots.

&&

.LONG TERM /FRIDAY THROUGH WEDNESDAY/...
Issued at 154 AM EST Thu Nov 7 2024

Guidance continues to suggest a dry period with above normal
temperatures through Saturday thanks to high pressure shifting
southeast through the Central Plains and Canadian Prairies. This
ridge will break down as a closed low exits the Desert Southwest and
lifts northeast into the Upper Great Lakes. The result will be an
occluded low moving east-southeast through northern Lake Michigan or
Upper Michigan Sunday night. Rain from this system will begin
spreading into the forecast area Saturday night, then end by Monday
morning. Recent ensemble and deterministic spread is trending toward
a more southerly track compared to last night, which is resulting in
a decrease in precip amount probabilities through Sunday morning. On
the high side of probabilities are the NBM and LREF, which suggest a
30-50% chance of exceeding 0.25 inches across the region.

A weak shortwave moving through Ontario may support a secondary
batch of light rain across the eastern portions of the forecast area
late Monday, but there are noted differences as to where the best
forcing will line up. This means precip could move in Monday
afternoon/night or remain locked up further north in Ontario where
the better forcing is expected. Ridging slides back into the region
Tuesday but kicks east as an amplified shortwave presses out of the
Plains. This system looks to bring precip to the region late
Wednesday into Thursday night with prospects for lake effect snow
Friday. Ensemble means of the EPS, GEFS, and GEPS all suggest a
favorable track for impactful snow, but surface low clustering of
these ensemble systems spans the Great Lakes, Ohio Valley, middle
Mississippi River Valley, and even central Ontario. This very poor
clustering just happens to have the mean in the middle overhead.
While options presented by model guidance do include the potential
for impactful snow, the current probability for this is very low
(10%).

&&

.AVIATION /06Z TAFS THROUGH 06Z FRIDAY/...
Issued at 1124 PM EST Wed Nov 6 2024

VFR will prevail at SAW through the forecast period and most of the
period at IWD and CMX. IWD and CMX will see MVFR cigs Thu morning
for a time.

&&

.MARINE...
Issued at 154 AM EST Thu Nov 7 2024

Guidance has been consistent run to run between this and the
previous forecast package. Main hazard continues to be the high end
southwesterly to westerly gale tonight across all of Lake Superior
associated with weak cold air advection and a compressing pressure
gradient. Guidance continues to highlight some potential upwards of
50kts, but this potential appears to have held fast near 25%.
Overall, will maintain the inherited gale warning but include that
some storm force gusts north of the Keweenaw will be possible.

Winds lighten below 20kts in west Friday morning and east in the
afternoon as a 1024mb high moves east across the Central Plains of
CONUS and Canada. This high will continue through the Great Lakes
into Saturday while building to 1028mb. Upstream in the Central
Plains on Saturday, a surface low will organize and begin lifting
northeast. This will bring southerly winds to around 20-25 knots on
Saturday. The low is expected to reach the Straits of Mackinaw
Sunday evening, but I am not expecting winds >25kts Sunday into
Monday.

&&

.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
  Wind Advisory from 5 PM this afternoon to 1 AM EST Friday for
     MIZ001-003.

Lake Superior...
  Gale Warning from 2 PM EST /1 PM CST/ this afternoon to 4 AM
     EST /3 AM CST/ Friday for LSZ162-240>244-263-264.

  Gale Warning from 7 PM this evening to 7 AM EST Friday for
     LSZ245>248-265>267.

Lake Michigan...
None.

&&

$$

SHORT TERM...LC
LONG TERM...JTP
AVIATION...07
MARINE...JTP