663
FXUS63 KAPX 141404
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
1004 AM EDT Tue May 14 2024

.KEY MESSAGES...

- Patchy frost potential tonight and again Wednesday night.

- Rain returns late Thursday Night into Friday

&&

.UPDATE...
Issued at 1004 AM EDT Tue May 14 2024

Current forecast remains on track as lingering showers along and
south of M-55 continue to diminish into early afternoon. For
forecast details, see the short term discussion below.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 302 AM EDT Tue May 14 2024

Pattern Synopsis/Forecast: Southern stream mid-upper level wave
currently over MO supporting an attendant area of surface low
pressure over the middle Mississippi Valley. This cyclone treks by
to the south over the next 24 hours -- situated over the Ohio Valley
by 12z Wednesday. Surface boundary currently over southern Michigan
will follow suit...slowly sagging to the south through the day
ahead. Surface high pressure builds across Hudson Bay and northern
Ontario, nosing into the northern Great Lakes through the duration
of the short term forecast period.

Forecast Details: A seasonably chilly start across northern Michigan
this morning with lingering light rain showers near and south of M-
55. Clear skies over the northern half of the forecast area
correlating with the coolest temperatures. Mostly sunny skies
anticipated for the day ahead with clearing continuing to slowly
progress from north to south. That said, smoke-allowing hi-res
guidance suggests wildfire smoke from Canadian wildfires may present
itself again today with some haziness (although in less
concentration than yesterday). High temperatures this afternoon
ranging from the mid-60s to low 70s for many interior areas
with cooler readings anticipated at the lakeshores.

Mostly clear skies and light winds expected tonight aiding to
promote decent radiational cooling conditions. Lows expected to fall
to the mid-upper 30s across the typical interior cold spots with
lower 40s more common near the coasts. Some patchy frost not out of
the question in the coldest spots.

&&

.LONG TERM /WEDNESDAY THROUGH MONDAY/...
Issued at 302 AM EDT Tue May 14 2024

PATTERN SYNOPSIS/FORECAST:

Flow aloft over the Great Lakes remains weakly northwesterly...with
PV strand slipping by...aiding in shunting a cold front south of the
area, into southern Lower MI. Cold front extends from this
southwestward into IA and MO, where it meets a couple surface lows
beneath a pesky upper low, and then drapes back into the central
Plains. Best moisture remains along and south of this front, and
especially along the Gulf Coast where another bit of energy is
keeping things active. Upstream...troughing over the western US,
with a shortwave and attendant surface reflection over
Alberta/MT/ID...and a bit of shortwave ridging ahead of this over
Manitoba, with a 1020mb surface high centered over northern Manitoba
as a result.

Expecting upstream ridge axis to slip into the vicinity today into
Wednesday...with quieter weather in response. However...niblet out
over the Intermountain West attm should try to slip into the Upper
Midwest/Great Lakes going into Thursday and Friday. This should
bring the next shot of rain chances into the area Thursday, though
it could be a bit of a drawn out situation, perhaps not all that
dissimilar to the last couple days, with a northern stream trough
axis slipping in while another niblet churns across the
central/southern US. Beyond Friday, however, still a great deal of
uncertainty in how the upper level pattern will pan out,
particularly in how deep and progressive upstream troughing ends up.
While there should still be some shot at periods of unsettled
weather, this uncertainty in the pattern also makes the weekend
fairly unclear attm...as it could mean the difference between more
or less of Saturday being pleasant/warm. Even less confidence in the
start of next week, depending on how quickly ridging builds across
the eastern US. If this ends up being slower, not out of the
question we could be looking at frost concerns for the end of the
weekend/early next week...but will hold off on nailing anything down
till there is better confidence in the situation. Stay tuned.

Primary Forecast Concerns:

Patchy Frost potential Wednesday Night...High pressure should be a
little better situated for us to see a better setup for frost
Wednesday night. Signals are improving for decoupling winds
overnight...and think it will be drier and clearer than currently
anticipated given generally easterly flow. (Have trended dewpoints
down for Wednesday/night, though have not gone as aggressive as
possible, particularly since we are in greenup now and there`s a
little better shot for evapotranspiration.) For now...have temps in
the mid 30s over the usual cold spots (i.e., Grayling down toward
Cadillac)...and will leave further tweaking to future shifts as we
get closer.

Rain Returns late Thursday Night into Friday...aforementioned dry
conditions on tap for Wednesday (and likely into Thursday) should
also nibble away at the leading edge of the moisture shield
Thursday...particularly noting signals for the mid-levels (around
700mb-ish) to remain rather dry. Have gone ahead and slowed this in
the forecast...though it appears we start to get enough top down
saturation and forcing to start getting rain to the surface by
late afternoon/evening from west to east. Guidance soundings suggest
lower stability overall aloft, which, combined with pwats ramping up
toward an inch or better, could lead to some better rainfall totals
by Friday morning...especially with the potential for some weak
elevated instability that could produce a little thunder (or at
least, embedded convective elements). Do have to wonder if some
portion of the area will end up fairly wet (perhaps 24-hr totals
around an inch?) Friday into Friday night as there`s some potential
for the system to be a bit slow moving, which could allow rain to
fall over largely the same areas for a while. Probabilities for this
idea are low attm (greater confidence in closer to a quarter inch or
so)...but not zero, so think this could be worth keeping half an eye
on.

&&

.AVIATION /12Z TAFS THROUGH 12Z WEDNESDAY/...
Issued at 542 AM EDT Tue May 14 2024

Primarily VFR through the TAF period with mid-cloud at TVC/MBL
giving way to passing high clouds at times, along with
smoke/haze from upstream Canadian wildfires possible again
today. While chances are very low and won`t be reflected in the
TAFs, brief MVFR VSBY restrictions at northern lower MI
terminals can`t entirely be ruled out as a result of that
smoke/haze. Northeast winds today sustained AOB 10 kts with
localized gusts of 15-20 kts turn light/calm tonight.

&&

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

&&

$$

UPDATE...DJC
SHORT TERM...MJG
LONG TERM...FEF
AVIATION...MJG