668
FXUS63 KMQT 181131
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
731 AM EDT Thu Jul 18 2024

.KEY MESSAGES...

- Dry weather through Friday.

- Best chances for rain/isolated thunderstorms (up to 50%) in
  the interior west on Saturday. Impacts should be minimal.

- Daily 20-30% thunderstorm chances through much of the extended
  period.

&&

.SHORT TERM /THROUGH THIS AFTERNOON/...
Issued at 328 AM EDT Thu Jul 18 2024

Current RAP analysis and WV imagery show the positively tilted mid
level trough axis now centered over southern Quebec with a 1022 mb
high pressure centered over MN. With the trough out of the way,
skies have cleared across the UP. This alongside the dry northerly
flow and near calm winds has allowed radiative cooling to bring
temps down into the 40s to low 50s. As we continue to cool down
ahead of sunrise, temps in prone low lying cold spots may still dip
into the 30s yet. Some patchy fog is possible where temps have
reached the dewpoints, although widespread restricted visibility is
not expected.

As the high pressure continues to build over the Great Lakes, low
level winds will turn more westerly and WAA will bring temps near
normal today with highs expected in the 70s. Some lake breezes are
also expected off the Great Lakes this afternoon, leading to some
variability in the winds. With mixing, min RHs will drop into the
30s. That said, there are no wildfire concerns today given that
winds will remain light below 15 mph. Outside some diurnal cumulus
that looks to develop over the interior west and south central UP,
quiet and dry conditions are expected today.

&&

.LONG TERM /TONIGHT THROUGH WEDNESDAY/...
Issued at 456 AM EDT Thu Jul 18 2024

Strong subsidence/high pressure will keep the air column dry through
Friday per forecast soundings.  Thus, plenty of sunshine will
continue with a weak warming trend by Friday.  Daytime highs will
climb back into the 80s where they`ll stay for much of the extended
period.  And, overnight lows will generally be in the 50s. But, some
of the cold prone spots of the interior west could dip into the
upper 40s tonight and low 50s at times throughout the period
dependent on radiational cooling.

Outside of the dry weather, there will be some exceptions for
shower and thunderstorm chances. The first will arrive on
Saturday as an upper low drops southeast from the Hudson Bay
into Quebec, while its associated cold front moves southward
across Lake Superior/Upper Michigan. With limited moisture,
widespread convective activity is not expected. However, some
isolated showers/thunderstorms cannot be ruled out Saturday
afternoon mainly across the southwest/south-central U.P. with
reinforcement from diurnal heating (40-50% chances). Further
out, perturbations in the upper flow and a stalled surface
frontal boundary to the south could be catalysts for daily
diurnally driven showers/thunderstorms (20-30%) at times
throughout much of the long term period. Least coverage and
lowest chances (10%) will be Sunday afternoon with any activity
that does form mainly confined to the WI/MI border out west.

&&

.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 731 AM EDT Thu Jul 18 2024

VFR flight conditions are expected to prevail throughout the entire
duration of the 12Z TAF period as high pressure extends over Upper
Michigan. Somewhat variable light winds this morning turns north-
northwest at IWD and SAW by late morning with winds remaining west
at CMX. A lake breeze component will have an impact on winds in the
afternoon and evening hours. Some diurnal cumulus clouds are
expected to form this afternoon with the best chances for
development near SAW. That said, this likely will have no impact on
aviation at the TAF sites. Skies clear out tonight as winds turn
light, becoming west to southwest for Friday.

&&

.MARINE...
Issued at 505 AM EDT Thu Jul 18 2024

After light winds today with high pressure overhead, southwest winds
will gust to 25 knots on Friday, mainly between Isle Royale and the
Keweenaw. By Friday night, winds will fall below 20 knots where they
will stay through the end of the forecast period. In addition, wave
heights will also remain below 4 feet through the forecast period.

&&

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

&&

$$

SHORT TERM...Jablonski
LONG TERM...TDUD
AVIATION...Jablonski
MARINE...TDUD