071
FXUS63 KMQT 102317
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
717 PM EDT Wed Jul 10 2024

.KEY MESSAGES...

- Patchy fog west tonight.

- Showers and thunderstorms enter the picture again over the
weekend. Severe storm risk will need to be monitored for Sunday and
Monday, maybe Tuesday as well.

- Very warm over the weekend with high temperatures well into the
mid and upper 80s F. About a 10% chance of widespread high
temperatures at or above 90F. Cooling trend begins Monday.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 242 PM EDT Wed Jul 10 2024

As the remnants of Beryl move northeast into New England this
evening, surface ridging over northern Ontario will build southward
across the Upper Great Lakes. Other than an isolated shra or two
near the WI line early this evening skies will be mainly clear with
light winds. With near optimal cooling conditions, patchy fog will
develop across the interior west after midnight. Temperatures will
cool to the lower to mid 50s for most but interior west
typically cooler locations will fall into the mid 40s.

&&

.LONG TERM /THURSDAY THROUGH WEDNESDAY/...
Issued at 316 PM EDT Wed Jul 10 2024

Last 24hrs of medium range model runs have maintained consistency on
the large scale evolution of the flow across N America over the next
7 to 10 days, and if anything, agreement has improved a little.
There has been slight progression of western N America mid-level
ridging and central N America troffing over the last 24hrs. This
progression will continue over the next few days as a shortwave
moving off of the ne Pacific into Canada flattens the ridge and
forces height rises/positive height anomalies to spread downstream
across southern Canada. A second wave will quickly follow off of the
ne Pacific Fri/Sat. As ridging then rebuilds over western N America,
that wave will be forced se, leading to modest trof amplification
over eastern Canada and the ne U.S. during the mid week period next
week. For Upper MI, this evolution of the pattern will support a
drier pattern to finish up the work week. There are still
indications for a shortwave to pass early weekend, supporting the
potential of shra/tsra later Sat/Sat night. The next potential of
greater coverage pcpn events as well as possible svr storms will be
late weekend/early next week in advance of and in association with
the onset of eastern troffing. As for temps, the spreading of
positive height anomalies downstream across southern Canada will
herald a warming trend beginning Thu, leading to a very warm/humid
weekend with highs well into the 80s to 90F. Cooler weather will
follow once eastern troffing develops early next week. Still looks
like there will be a couple of pleasant U.P. summer days in the
midweek period next week as Canadian high pres settles over the
Great Lakes region.


Ridging recovers Thursday as the remnants of Beryl move through
southern Quebec. With an otherwise light wind field, lake breezes
should rule the day.  However, a very dry column will preclude any
convection, perhaps with just some cumulus popping along the
boundaries. As we`ll be on the back edge of the ridge Friday, winds
increase out of the SW and usher in a warming trend. High temps in
the mid 70s to lwr 80s on Thu will rise to mostly the 80s on Fri.
Expect locally cooler conditions along Lake Superior and Lake MI on
Thu and mainly just near Lake MI on Fri as a s to sw gradient wind
takes over.

Over the weekend, warming under sw flow will send high temps well
into the mid and upper 80s F. Widespread values around 90F area-wide
are becoming less likely, but NBM continues to highlight our s/sw
downsloping areas for a high probability (60-90% chance) of highs
around or in excess of 90F for Sat-Sun. With lows through the
weekend only in the lower to mid 60s, we won`t have much relief from
the heat overnight. Additionally, dewpoints in the 60s will keep
things feeling rather muggy.

Arrival of a shortwave supports the potential of sct shra/tsra Sat
aftn/Sat night. Then late weekend/early next week, timing of main
shortwave that brings cooling to the area is still fairly uncertain.
However, ahead of that wave, models continue to show other subtle
waves that will be progressing thru wnw flow into the Upper Great
Lakes Sun-Tue. Given the substantial instability that will build due
to the very warm/humid conditions over the Upper Mississippi
Valley/Upper Great Lakes and the climatologically favored wnw flow
regime for summer svr storms in Upper MI, there will be a risk of
svr storm complexes with these waves. Of course, at this time range,
timing of these subtle waves and the resulting convection, including
where convection develops, is highly uncertain. Will certainly be
something to monitor Sun as an EML nosing into the Upper Midwest or
Great Lakes potentially leads to even steeper values of CAPE. Much
of the guidance available at that range also shows sufficient deep
layer shear to sustain updrafts. Though soundings are less
impressive on Monday, the threat for strong/severe convection is
still worth monitoring then, and maybe Tuesday as well. Fcst
reflects a broad brushing of chc pops, generally 30-40pct, Sun thru
Tue. Cooling should get underway Tuesday into the middle of the week
as the main trough drops through, leading to what should be pleasant
U.P. summer weather Wed/Thu as Canadian high pres settles over the
Great Lakes.

&&

.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 716 PM EDT Wed Jul 10 2024

Mostly clear skies will prevail in this period. However a brief
period of low MVFR ceilings will be possible at KSAW this evening
early in the TAF period. The clear and calm conditions overnight
will allow fog/mist to develop tonight. Visibilities may dip down to
MVFR and IFR. KIWD may periodically see LIFR vis. Expect the
fog/mist to lift and mix out after sunrise.

&&

.MARINE...
Issued at 316 PM EDT Wed Jul 10 2024

A weak pres gradient will dominate over and in the vcnty of Lake
Superior for the next several days. Result will be winds across Lake
Superior under 20kt and often under 15kt. Some increase in winds may
occur over the weekend with high pres to the se and low pres
troffing to the w and nw.

&&

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

&&

$$

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