815
FXUS63 KMQT 111114
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
714 AM EDT Mon Aug 11 2025

.KEY MESSAGES...

- A few showers lift northeast across the east half this
  morning. Additional showers and a few thunderstorms are
  possible in the east along the lake breeze this afternoon.

- Poor air quality returns today and Tuesday. See the latest
  Air Quality Alert, issued by Michigan`s Department of
  Environment, Great Lakes, and Energy for additional
  information.

- High temperatures remain above-normal to near-normal
  throughout the week.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 412 AM EDT Mon Aug 11 2025

Early morning RAP analysis and GOES satellite imagery reveal a broad
trough extending SW from the Canadian Prairie provinces down into the
southern Plains and a weak embedded shortwave passing overhead
WI/MI. At the surface, low amplitude sfc troughing and a diffuse
cold front is working across Lake Superior. Weak isentropic ascent
ahead of the boundary associated with the wave is forcing an area of
light rain into the s-central UP and a few thunderstorms further
east over Lake Michigan. A decrease in detected lightning strikes
and warming clouds tops suggest little to no thunderstorm potential
across the UP, though I suppose a clap of thunder isn`t out of the
question given weak elevated instability.

Through the morning and early afternoon, expect shower activity to
lift NE through the east half of the UP and clearing to work its way
from west to east amidst slight pressure rises. With the drier
airmass aloft and 850 temps 13-15C, this will provide a pretty
pleasant day with sfc high temps averaging the low 80s. Dewpoints in
the mid 60s to near 70 continue to linger across the s-cental and
east, keeping conditions a bit more muggy than the west half, where
more desirable Tds in the 50s are expected. Otherwise, with slight
pressure rises and quasi-zonal flow aloft ahead of an approaching
shortwave, lake breeze development is likely across the east half
this afternoon. There, 00z HREF probabilities for >500 j/kg of
SBCAPE are rather unimpressive, only reaching 60-70% by peak
heating. Should instability be a bit more plentiful, the lake breeze
may kick off a few showers and thunderstorms along the M-28
corridor. CAM guidance is hit or miss, thus have opted for low
chance (<30%) PoPs for isolated convection across the east half this
afternoon/evening.

Another concern for the start of the work week is Canadian wildfire
smoke returning to the region. See the latest Air Quality Alert for
additional information.

Mostly clear skies and slightly lower humidity will allow overnight
lows a few degrees cooler than recent nights where the interior may
be able to break 60.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
Issued at 411 PM EDT Sun Aug 10 2025

Precip returns to the forecast on Tue as a deeper trough extending
from MN up along the Manitoba/Ontario province line will be at the W
flank of the CWA by 12Z Tue. This trough shifts over Ontario,
bringing a ~996mb sfc low across far N Ontario and pivoting the
southern end of the trough and attendant cold front over the UP
during the day. This system brings better instability, bulk shear,
and forcing for convection, but is lacking in deep available
moisture. Will want to watch this round regardless as it does
present some potential for strong to severe storms.

From there a dry period sets up for mid week as a mid level ridge
over the N Plains moves over the Great lakes and high pressure
tracks over E Canada, extending ridging down into the Great Lakes.
Slightly cooler temps are expected in the wake of the cold front on
Tue with highs Wed/Thu in the 70s and lows Wed night in the 40s to
mid 50s, coldest interior. This rebounds back above normal for the
end of the work week into the weekend as low level S flow returns.
Quazi-zonal flow aloft returns into the weekend which lowers
predictability, but passing shortwaves keep chance PoPs in the fcst.

&&

.AVIATION /12Z TAFS THROUGH 12Z TUESDAY/...
Issued at 713 AM EDT Mon Aug 11 2025

VFR conditions are expected to prevail for much of the 12z TAF
period, the exception being SAW early this morning under passing
light rain showers. IFR to MVFR cigs may linger at SAW through at
least 15z, however, drying conditions are on the way from the west
as shown by latest satellite and radar trends. This afternoon, light
west winds below 15 kts are expected alongside afternoon lake breeze
development. No precipitation is expected once showers clear to the
NE this morning. Some convection may develop in the east half of the
UP along lake breeze development, but is not expected to impact and
TAF sites.

&&

.MARINE...
Issued at 411 PM EDT Sun Aug 10 2025

Southerly flow will largely prevail through mid-Tuesday across Lake
Superior thanks to the persistent broad troughing positioned just
upstream in the Northern Plains. Surface troughs will press through
tonight and again Tuesday, which will support a period of westerly
winds afterwards. Northwesterly winds establish themselves Tuesday
night after the cold front finally swings through. Winds will
largely fall in the 15-25 kt range in this period save for gusty
winds associated with passing thunderstorms. Thunderstorm potential
mostly focuses this evening through tonight across the east half of
Lake Superior and then a slow moving, west to east line of showers
and storms late Monday night into Tuesday. Hazards with any of these
storms will be lightning and visibility reductions from potential
heavy rain and post-rain fog that may develop.

&&

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

&&

$$

SHORT TERM...BW
LONG TERM...Jablonski
AVIATION...BW
MARINE...JTP