921
FXUS63 KAPX 181742
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
142 PM EDT Wed Sep 18 2024

.KEY MESSAGES...

- Warm temperatures and rain-free through the work week

- Perhaps rain chances emerge Fri night into Saturday

&&

.UPDATE...
Issued at 1032 AM EDT Wed Sep 18 2024

More of the same today with sunny skies and very warm
temperatures. Not quite as warm as the last few days with most
spots topping out in the lower 80s this afternoon with light
winds.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 328 AM EDT Wed Sep 18 2024

Pattern/synopsis: High pressure extends west into northern MI.
This ridge axis is somewhat further north than 24 hours ago.
Weak southerly return flow continues.

Forecast: A little bit more in the way of moisture will be drawn
northward today. Dew points should not mix out quite as
aggressively this afternoon, and we even support a few cu
clouds, especially in the se. That`s what passes for excitement
today. Adding circa 3f to consensus guidance Max T yesterday
ultimately was about 1-2f too warm. So only tacked on 1f today.
Highs from near 80f to the mid 80s. If dew points do maintain
themselves a little higher, that would result in milder min
temps tonight, but also a bit more in the way of fog potential.
Lows tonight near 50f thru the 50s.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Issued at 259 AM EDT Wed Sep 18 2024

Warm and dry will continue Thursday, with an upper ridge still over
much of the central to eastern Great Lakes region. A pattern change
is possible staring Friday as a negatively tilted upper closed low
over central/southern CA continues to trek to the NE. This will
likely help kick off convection over MN Thursday. As convection
moves eastward, the upper low will continue to track northward and
detach from a weakening surface front. Although forcing isn`t the
best, around 20-30kts of shear will exist. Guidance has also been
trending up with moisture availability (PWATs in deterministic
guidance have doubled over the last few runs to reach 1.5").
Although this seems optimistic, it does result in at least a few
hundred J/KG of SBCAPE Friday afternoon and MUCAPE Friday night into
Saturday. At this time, ingredients for storms still seem poorly
organized and timed (SBCAPE, LL/mid lvl lapse rates, and shear don`t
ideally overlap). However, a scenario that could be seen is
convection moving in from the west and not dying right after it
reaches the CWA line but lingers a little. These chances for
rain/storms continue to not show signs of impacts besides possible
lightning strikes where fuels have been drying.

Temperatures will likely cool Sunday as winds breifly turn
northerly. Global ensemble guidance continues to show confidence for
more rain and cooler temperatures in the forecast early next week,
however exact amounts and timing will continue to be up for debate.

&&

.AVIATION /18Z TAFS THROUGH 18Z THURSDAY/...
Issued at 139 PM EDT Wed Sep 18 2024

High pressure remains in control through the taf period. Clear
skies and light winds will likely lead to the formation of
patchy ground fog once again late tonight into early Thursday.
Winds will remain generally light. VFR conditions except for
possible lower VSBYS/CIGS in fog.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.

&&

$$

UPDATE...AJS
SHORT TERM...JZ
LONG TERM...ELD
AVIATION...AJS