794
FXUS63 KMQT 150715
AFDMQT

Area Forecast Discussion
National Weather Service Marquette MI
315 AM EDT Sun Sep 15 2024

.KEY MESSAGES...

- A chance (15-50%) of showers and storms today into Monday
  over mainly the west half. Otherwise, the prolonged dry
  stretch will continue through this week.

- Extended stretch of well above normal temperatures continues
  through the forecast period with highs mainly in the upper 70s
  and 80s.

&&

.SHORT TERM /THROUGH THIS AFTERNOON/...
Issued at 313 AM EDT Sun Sep 15 2024

Water vapor imagery and RAP analysis show mid-level troffing from
the w half of Canada into the western U.S. Downstream, mid-level
ridging continues to dominate the Great Lakes region, though it has
drifted e a bit over the last 24hrs. Mid-level anticyclone that was
centered centered just e of the Soo at this time yesterday is now
centered just s of Georgian Bay. Btwn this feature and the troffing
to the w, mid-level ssw flow is present across Upper MI early this
morning. While nothing of note particularly stands out in this ssw
flow, models do depict a couple of subtle shortwaves. Those waves
are aiding a modest expansion of sct shra across western Upper MI,
especially nw Upper MI, over the last few hrs. Many of the 00z
models correctly captured this increase in shra. Otherwise, it`s an
unseasonably warm night across the w where clouds and light winds
continue to hold temps up into the mid and upper 60s F, 20+degrees
above the normal low temps for this time of year. To the e, with
only sct thin high cloudiness, temps have fallen into the lwr 50s at
traditional interior cool spots.

Fcst this morning will follow the model consensus, which suggests
shra will continue to lift across western Upper MI thru about 12z,
then the shra will depart from sw to ne. With fcst soundings showing
a skinny cape profile, thunder potential is very limited early this
morning. Might be a rumble of thunder. With departure of the shra,
clouds will also thin out. For the most part, a mostly sunny aftn is
anticipated, setting up a very warm day under 850mb temps at around
16C. High temps in the low to mid 80s F will be the rule, generally
15-20 degrees above normal for time of year. S to se winds will hold
temps to the 70s F near Lake MI and along the e side of the
Keweenaw. With dwpts a little higher than recent days, MLCAPE over
western Upper MI increases to near 2000j/kg at the high end per NAM.
Lower end of the model guidance is down around 800j/kg. General lack
of lake breeze development off of Lake Superior is a missing
focusing mechanism, but with fcst soundings suggestive of no cap or
only a very weakly capped environment and with several of the 00z
models indicating some convective development, fcst will reflect 15-
20pct chc of aftn shra/tsra (isold coverage if anything develops)
across portions of western Upper MI.

&&

.LONG TERM /TONIGHT THROUGH SATURDAY/...
Issued at 308 AM EDT Sun Sep 15 2024

BLUF: Mainly calm weather dominates the extended period, although
some light rain showers and some thunderstorms are possible over the
west tonight and Monday. Expect the late summer-like conditions to
continue through the week, although temperatures may slightly
decrease late this week as troughing approaches from the west by
next weekend. Therefore, if you can, enjoy those outdoor activities
while you still can!

Some isolated rain showers and a thunderstorm or two are possible
over the western U.P. late tonight through Monday as a shortwave
riding along the ridging over the Great Lakes moves overtop us.
While plenty of instability is available in the atmosphere by the
Monday afternoon hours, with the better forcing located to our west
and north, rain showers and storms will have a difficult time firing
up. Therefore, any convection that we do see late tonight through
Monday will more than likely be dependent on hard to pin down
mesoscale/local variables, such as storm dynamics and localized
topography. With the better PWATs further to our west and north too,
not much rainfall is expected to fall out of the showers and storms
we do see; expect no more than a quarter of an inch in the heaviest
rain spots, with many areas even over the west failing to receive
anything.

Expect the rest of this week to be dry as high pressure ridging
settles across the Upper Great Lakes while troughing digs into the
western U.S.. While the warmest day is expected on Monday with highs
possibly getting into the mid to upper 80s in the interior areas,
the rest of the work week is very likely (80+%) to see high
temperatures in the upper 70s to lower 80s, with mostly sunny skies
dominating overhead due to the ridging. Fire weather concerns should
be limited this week due to the light winds and more "moist" min
RHs. However, fuels may need to be monitored as the lack of rainfall
could further dry them out. By next weekend, model spread increases
amongst the differing suites. However, there is still a general
trend to push the timing of incoming rainfall back to the end or
past the end of the extended period. Therefore, I`m highly doubtful
(80+% chance) that we will see rainfall over our area until at least
early next week. However, we could see cloud cover increase from the
west as the troughing slowly tries to battle its way into our neck-
of-the-woods this next weekend; this increase in clouds would drop
our daytime high temperatures closer to normal.

&&

.AVIATION /06Z TAFS THROUGH 06Z MONDAY/...
Issued at 131 AM EDT Sun Sep 15 2024

VFR will prevail at IWD/CMX/SAW thru this fcst period. However,
a disturbance will continue its track into northern Ontario
early this morning, resulting in scattered rain showers over
western Upper MI. IWD/CMX may occasionally be affected,
especially CMX where a mention of MVFR vis in -shra/br was
included thru 10z. Thunderstorm threat is too low to include
mention. Winds will remain light and mainly southerly.

&&

.MARINE...
Issued at 308 AM EDT Sun Sep 15 2024

Light winds of 20 knots or less continue through this week as
ridging remains over the Upper Great Lakes. Nevertheless, we could
see a few showers and thunderstorms over Lake Superior today through
Monday as some shortwave action rides along the ridging overtop us.

&&

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

&&

$$

SHORT TERM...Rolfson
LONG TERM...TAP
AVIATION...Rolfson/TDUD
MARINE...TAP