Gaastra, Michigan Weather Forecast Discussion

854
FXUS63 KMQT 291803
AFDMQT
Area Forecast Discussion
National Weather Service Marquette MI
203 PM EDT Mon Sep 29 2025
.KEY MESSAGES...
- A mostly dry and low impact weather pattern with near to above
  average temperatures holds this week.
&&
.DISCUSSION...
Issued at 202 PM EDT Mon Sep 29 2025
Afternoon satellite imagery reveals mostly clear skies overhead the
Great Lakes down to the Ohio River Valley as an upper ridge axis
extends NW from the SE Conus towards the Northern Plains and sfc
high pressure is placed atop the Lower Great Lakes. Meanwhile, a
broad trough encompasses much of the western third of the Lower 48
with a few subtle embedded waves producing nothing more than mid to
high cloud cover in the N Plains given a dry sfc layer in play.
Closer to home, a ~1028 mb sfc high pressure is moving SE through N
Ontario on the western flank of a far E Canada trough. This is
supporting a "backdoor cold front" which isn`t much more than a
northerly wind shift across northern Lake Superior at this point.
Otherwise, afternoon RHs have managed to fall as low as 35% for some
interior portions of the UP, but coupled with light winds and no
further drastic drying, there are no fire weather concerns at this
time.
Tonight, expect a mostly clear night save for some high clouds and a
northerly wind shift associated with the approaching backdoor front.
Low temps fall to the low 50s to mid 40s. Continued warm and dry
weather is favored into the mid week period. Breezy low level E to
SE flow will kick temps down a few degrees (mid 70s to upper 60s)
Tuesday and Wednesday as the aforementioned Ontario sfc high presses
into Quebec and the upper ridge axis shifts over the Great Lakes.
Precipitation chances finally return this weekend as the upper ridge
begins to break down, allowing the return of more formidable
moisture and shortwave energy to flow back into the region. While
details at this time range remain murky, global models and ensemble
guidance hint at possible showers and thunderstorms in the
Friday/Saturday time range. Opting to leave in chance PoPs brought
in by the NBM at this time.
&&
.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 1243 PM EDT Mon Sep 29 2025
VFR conditions are expected to continue over the TAF sites as high
pressure ridging persists over the region. However, some of the
model guidance such as the LAMP and NAM have upslope FG developing
over CMX tonight; while I left it out of the TAF for now because I
think the chances of it actually occurring are too low given the
dryness and high pressure overhead, I`m mentioning it here as there
is a notable non-zero chance that it could occur given the overnight
easterly upslope winds (while non-zero, chances are much, much lower
for FG over IWD and SAW late tonight too). Speaking of the winds,
expect the generally SW to W winds this afternoon to become more
E`rly tonight and to pick up a little Tuesday morning as low
pressure troughing begins to develop over the Northern Plains.
&&
.MARINE...
Issued at 202 PM EDT Mon Sep 29 2025
Calm S to SW winds prevail this evening ahead of a backdoor cold
front that slides through tonight, veering winds to the N to NE
tonight before upticking to 15-25 kts by sunrise tomorrow morning,
persisting through the afternoon mainly across the western arm of
the lake and around the Keweenaw Peninsula. Winds fall below 20 kts
Tuesday night before veering S to SE Wednesday and becoming gusts to
25 kts again. These gusty southerly winds persist through the late
week.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
None.
Lake Michigan...
None.
&&
$$
DISCUSSION...BW
AVIATION...TAP
MARINE...BW

NWS MQT Office Area Forecast Discussion