540
FXUS63 KAPX 261930
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
330 PM EDT Sun May 26 2024

.KEY MESSAGES...

- Showers chances thru Tuesday. Thunderstorms possible
  tonight/early Monday, and Tuesday afternoon and evening.

- Drying trend starts Wednesday.

&&

.SHORT TERM /THROUGH MONDAY/...
Issued at 327 PM EDT Sun May 26 2024

Pattern/synopsis: A reasonably vigorous shortwave is crossing
the upper MS Valley. This will slowly cross northern MI early on
Monday. At the surface, low pressure over far eastern IA will
move ne, also crossing northern lower MI Monday morning.

Forecast: Ugly, at least for this time of year. Skies are
largely overcast with cirrus, which is lowering into a mid
cloud deck in nw lower MI. Light virga is pushing into sw
sections; actual precip is likely to break out at MBL after 5pm.
Increasing return flow, and increasing forcing ahead of the
ejecting lows, will combine to spread showers across the
forecast area tonight. Southerly 1-km winds increase to 30-35kt
over southern lower MI tonight, aiding in moisture input into
northern MI. Numerous to widespread showers will invade from sw
to ne, with additional development later tonight. Lows in the
low-mid 50s.

Currently, thunder is found well to our south, but instability
will weaken with northward extent. For most of the evening and
night, do not expect more than a few rumbles of thunder.
However, later in the overnight, a more prominent plume of
instability may impact southern areas (near and south of M-72).
Even so, well-elevated MuCape pushing 500j/kg should not result
in a svr threat.

Monday/Memorial Day: Even as the lows eventually depart in the
afternoon, leftover troffing and cyclonically-curved flow will
support some showers in eastern upper, nw and n central lower
MI. Pops do decrease somewhat during the day in se sections.
Otherwise cool, damp, somewhat brisk, and showery all day long.
Highs from the upper 50s near Lake MI and Superior, to the mid-
upper 60s near Saginaw Bay.

&&

.LONG TERM /MONDAY NIGHT THROUGH SATURDAY/...
Issued at 327 PM EDT Sun May 26 2024

Pattern Synopsis and Forecast: A broad area of lower upper level
heights persists over Ontario CA Tuesday. This help to linger
precipitation chances over eastern upper and northern lower
overnight Monday into Tuesday. Most global models show a second
upper low reach WI Tuesday afternoon, and open up into a shortwave
as it moves over MI Tuesday late afternoon/evening. This wave will
help to carry a cold front as it moves across the CWA. A few spots
could clear Tuesday late morning/mid day before the front and
shortwave move over, allowing temperatures near the surface to warm
a few more degrees than Monday. This could lead to around 500-800
j/kg of SBCAPE tuesday afternoon/evening ahead of the cold front
resulting in chances for scattered storms. Drier air through the
column settles in Wednesday, scouring out any more precipitation
chances for the remainder of the week. Colder morning lower will
likely be seen starting Thursday morning with warmer afternoons as
upper level ridging builds in by Friday. Winds should generally
remain light to breezy in the afternoon hours.

Primary Forecast Concerns/Key Messages: Guidance has been fairly
inconsistent with what will happen Tuesday, as multiple features are
in play before then. However, guidance has been keying in on a drier
and cooler air mass plowing southward from Canada the past several
runs. The details that get changed are the track and timing, which
the past few runs show the track of the front to move over northern
MI/WI instead of WI/MN/ND. Exact timing of the front will likely
become more clear once a few CAMs reach into Tuesday afternoon (this
next 18Z run). As of now, chances for severe storms remain low with
the likely scenario being isolated to scattered weak thunderstorms
that are able to product lightning, heavy rain, and marginally gusty
winds and small hail as they get closer to the Lk Huron coast (where
more instability will likely be).

Drier air behind the front will settle in for Wednesday. Combined
with chances for breezy afternoon winds, elevated fire conditions
could be seen Wednesday afternoon. As winds will likely diminish for
Thursday, and the cooler air anchors in, Thursday mornings
temperatures could be cold (mid 30s are in the forecast) which could
lead to chances for frost. We will be watching how this trends.

&&

.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 132 PM EDT Sun May 26 2024

Worsening conditions tonight.

Low pressure is in eastern IA. Showers and some embedded TSRA
are gradually spreading into the western lakes, ahead of the
low. These will reach MBL by early evening, then expand across
all sites into tonight. Best chance for TSRA will be later
tonight. Occasional vsby restrictions are expected. Cigs will
lower to MVFR and then IFR by very late tonight, into Monday
morning.

E to se winds will become somewhat stronger/gustier.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until 4 AM EDT Monday for LHZ345.
     Small Craft Advisory from midnight tonight to 4 PM EDT Monday
     for LHZ346>349.
     Small Craft Advisory until 4 AM EDT Monday for LMZ341-342.

&&

$$

SHORT TERM...JZ
LONG TERM...ELD
AVIATION...JZ