989
FXUS63 KAPX 310631
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
231 AM EDT Fri May 31 2024

.KEY MESSAGES...

- Return of above normal temperatures today.

- Temperatures gradually warm through the weekend, peaking in the 70s
  and 80s Sunday and beyond.

- Shower chances return to the picture Saturday, with another system
  potentially bringing the next more appreciable shower / storm
  risk Monday into Tuesday.

&&

.SHORT TERM /THROUGH TONIGHT/...
Issued at 228 AM EDT Fri May 31 2024

High pressure dominating the complete depth of the atmosphere early
this morning, with apex of mid/upper level ridging building into the
western Great Lakes, with the center of its surface reflection
running just a bit out ahead...centered across southeast Ontario and
Ohio. Attendant deep layer dry air and subsidence resulting in a
mostly clear and seasonably chilly night across the Northwoods...
with some of traditional colder interior areas already making a run
into the 30s.

Flow regime remains fairly progressive, with upper level ridge
building through and eventually east of the area today and tonight,
with its attendant surface refection reaching vicinity the east
coast by sunrise Saturday. Troughing builds in their wake into the
northern Plains later tonight/early Saturday, with a cold front
running along the leading edge of this trough into the upper
Mississippi Valley region by Saturday morning.

Primary Forecast Concerns/Challenges:

Cloud and temperature/dewpoint trends and addressing any late night
shower potential.

Details:

Dry conditions expected today under just some increasing high level
thin clouds. Increasing southwest return flow on backside of that
departing surface high will usher in an increasingly mild
airmass...and when combined with that late May sunshine, will help
temperatures recover quickly this morning. Expect temperatures to top
out well into the 70s (even a few areas reaching 80) this
afternoon. Per the usual, expect temperatures to run a touch cooler
near the big waters. Rather aggressive late morning/early afternoon
mixing and lack of any low/mid level moisture advection will force
relative humidity values to drop to near or below critical
levels...especially across northeast lower Michigan. While winds do
increase, just not seeing any real support for sustained critical
level wind gusts. Combine that with now nearly full green-up/recent
rains, and concerns for elevated fire weather concerns are
negligible.

Clouds will continue to increasing tonight as mid/upper level
moisture advection continues ahead of that approaching
trough/attendant cold front. Given antecedent dry low level
conditions and detachment of more collective forcing to our
west...thinking any threat for rain will now hold off until after
sunrise Saturday. A much milder night, with lows only dropping into
the lower and middle 50s.

&&

.LONG TERM /SATURDAY THROUGH THURSDAY/...
Issued at 228 AM EDT Fri May 31 2024

Pattern Synopsis / Forecast:

Meteorological equivalent of a traffic jam is the name of the
pattern set to grace northern Michigan through the course of the
long term period. 500mb ridging and associated surface high will be
forced south and east into the Carolinas over the weekend, all the
while two waves approach, but don`t entirely impact the Northwoods.
The first being a rotund vertically stacked low precariously
spinning over northern Saskatchewan and Manitoba, with associated
cold front decaying as it heads into the Great Lakes, fighting
parallel flow, and largely washing the front out. Second feature
will be a compact wave and associated surface low with convective
origins from ongoing robust thunderstorms over the southern Plains.
This wave passes through the mid Mississippi and Ohio valleys and
into the southern Great Lakes before departing for Sunday. Result
will be increased cloud cover, though not necessarily any overly
unsettled weather Saturday... best chances in the eastern Yoop with
the cold front, and toward M-55 with the southern low.

Ridge axis retrogrades somewhat, resulting in stronger southerly
return flow for Sunday ahead of a deeper wave set to pass through
Monday into Tuesday. Increased dewpoints will lead to somewhat
better potential for instability ahead of a cold front Monday
evening... and if the timing of the front is right, perhaps some
showers and storms across the region are possible. Beyond then,
another wave moves into central Canada, though with robust
amplification of a west coast ridge, should set up northwest flow...
but with current guidance suggesting deeper moisture holding south
and west of the upper Great Lakes, current thoughts are that the
majority, if not, all of any resulting convective waves will be
suppressed south and west through the Mississippi River valley
through the remainder of next week while we largely hold dry.

Primary Forecast Concerns:

Upcoming Rain Chances: Not going to sugarcoat things here...
frustrating precipitation forecast in the cards for the forecast
period. Influence of the southern wave likely leads to more
prominent cloud cover over much of northern lower, but stout dry air
presence in the low levels makes top-down saturation difficult owing
to a lack of a deeper moisture tap. Southern areas closer to M-72
and Saginaw Bay will have a better shot at some synoptically
generated rain as that compact wave passes through Indiana and Ohio,
but overall, probably a drier day than not for the rest of northern
lower... and it`s not out of the question that temps spike into the
mid-upper 70s across both the eastern Yoop and for points north of M-
72. Cold front may be able to generate some showers and thunder
across the eastern Yoop after 20z Saturday, but limited instability
(perhaps a few hundred joules of CAPE) and potential nocturnal
frontal passage timing may put the kibosh to shower and storm
potential. Next chance of rain will be Monday into Tuesday as a more
potent disturbance passes through. Still a bit of uncertainty
regarding this feature, particularly as the parent surface low is
set to ride the flow around the ridge well north into Ontario, which
usually suppresses convective potential here, especially if the
timing of the cold frontal passage is more nocturnal. Have elected
to cap PoPs under likely wording (54% or less) Monday evening into
the overnight owing to this uncertainty. Will have to continue to
monitor this feature in the coming cycles. Looking ahead,
aforementioned developing northwest flow likely kicks off MCS
Mania(TM) across the northern Plains. At this juncture, unfavorable
steering flow and deeper moisture suppressed away from the CWA
suggests that the bulk of these potential convective outbursts will
favor the Dakotas, south and east into the Ohio Valley.

&&

.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 1046 PM EDT Thu May 30 2024

VFR conditions are anticipated across northern Michigan into Friday
night. Clear/sunny skies will remain in place through Friday morning
before high clouds begin to move in from the west later in the
period. Weak/calm winds will strengthen to around 10 kts out of the
southwest by mid to late morning.

&&

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

&&

$$

SHORT TERM...AJS
LONG TERM...HAD
AVIATION...DJC