Chatham, Michigan Weather Forecast Discussion

472
FXUS63 KMQT 150712
AFDMQT
Area Forecast Discussion
National Weather Service Marquette MI
312 AM EDT Mon Sep 15 2025
.KEY MESSAGES...
- Warm and humid weather through early next week.
- Areas of fog are possible again tonight; fog could be dense.
- Cooler air moves back in for the late week.
&&
.SHORT TERM /THROUGH TONIGHT/...
Issued at 225 AM EDT Mon Sep 15 2025
As the omega block continues to slowly trudge eastward away from the
Upper Great Lakes today and tonight, expect the remnant ridging to
keep the area dry over the next 24+ hours, save for maybe a stray
shower/storm or two sneaking into the Ironwood area this evening
(15% chance or less). While we could still see patches to areas of
fog developing over the central and eastern U.P. early this morning,
it does seem like the likelihood of this occurring is pretty shaky
as of the time of this writing as it has not occurred yet, save for
around the L`Anse/Baraga vicinity. However, the most recent
observations are showing winds calming down and visibilities
beginning to lower in spots like Escanaba, Iron Mountain, and
Menominee; will continue to monitor the trends in satellite and
webcam imagery, as well as observations, in regards to any potential
fog formation. If any fog does form, expect the fog to once again
erode away by the mid-morning hours (like what happened yesterday).
As the ridging over our area slowly begins to erode away today,
expect sfc winds to pick up from the south (southeast over the
Keweenaw). That being said, with remnant ridging still being fairly
robust over us, the southerly winds shouldn`t gust much above 15 mph
by this afternoon (when max winds expected). The sunny skies
overhead and warm, moist air continuing to advect into the region
should allow high temperatures today to be a little warmer than
yesterday, with the western U.P. potentially getting into the mid
80s by the mid to late afternoon. In addition, we could see min RHs
get down to around 40% or even the upper 30 percents in a spot or
two. As we head into tonight, we could see fog redevelop over the
central and eastern U.P., although with the ridging weakening
overtop us, confidence in the fog occurring is lower in comparison
to previous overnight forecasts.
&&
.LONG TERM /MONDAY THROUGH SUNDAY/...
Issued at 322 PM EDT Sun Sep 14 2025
The upper level ridge will hold on through Tuesday and begin to
break down as a trough moves through the Upper Great Lakes on
Wednesday. The chance for showers and thunderstorms will come back
for midweek with the passage of the trough and a cold front. Models
are coming into better agreement that a low will cut off from the
trough as it pushes from the Rockies into the Midwest late this week
and take its time tracking through the Great Lakes through the
weekend. Temperatures Tuesday and Wednesday will be 10 to 15 degrees
above average with highs in the 70s and 80s. Cooler weather will
arrive for Thursday through the weekend with highs falling back into
the low to mid 60s, just a bit below average for this time of year.
For Friday through the weekend models keep a majority of the
precipitation south of the U.P though at least a slight chance
for showers is maintained through the weekend.
&&
.AVIATION /06Z TAFS THROUGH 06Z TUESDAY/...
Issued at 109 AM EDT Mon Sep 15 2025
FG/BR development is still anticipated at CMX/SAW early this morning
as temps reach dew points under mostly clear skies. That said, winds
remaining up longer than previously expected and limited low level
moisture is delaying development. IWD is no longer expected to see
any restrictions, though patchy BR ~6SM can`t be ruled out. SAW has
the best shot at reaching LIFR, but likely only will dip to IFR/high-
end LIFR briefly ahead of sunrise. CMX has slightly lower chances
than SAW, but does at least have the support of weak upslope flow
off Lake Superior. Once the morning BR/FG clears out, VFR returns
with SE winds around 10 kts.
&&
.MARINE...
Issued at 312 AM EDT Mon Sep 15 2025
Light winds of generally 20 knots or less are expected through most
of the week, although we may see some southerly winds up to 20 knots
this evening over the central lake as the high pressure ridging
overhead weakens. Some patches to areas of dense marine fog are
being seen over the far western lake early this morning. Because of
this, continuing the Dense Fog Advisory for the far western lake
until 10 AM CDT; will continue to monitor the latest satellite
imagery and any available observations in case the Dense Fog
Advisory needs to be expanded eastward. We could also see some stray
showers and storms over the far western lake by this afternoon and
evening as shortwaves ride atop the retreating omega block.
Thankfully, these just look to be garden-variety showers and storms.
As a shortwave low pushes in around the Wednesday time period,
bringing showers and storms across the lake Wednesday into Wednesday
evening. We may also see winds increase from the northeast too on
Thursday and Friday as well due to increased ridging from the north
interacting with a sfc low spinning over the Northern Plains as it
attempts to move eastward into the Great Lakes region heading into
this weekend.
&&
.MQT WATCHES/WARNINGS/ADVISORIES...
Upper Michigan...
None.
Lake Superior...
  Dense Fog Advisory until 11 AM EDT /10 AM CDT/ this morning
     for LSZ162.
Lake Michigan...
None.
&&
$$
SHORT TERM...TAP
LONG TERM...NL
AVIATION...Jablonski
MARINE...TAP

NWS MQT Office Area Forecast Discussion