322
FXUS63 KAPX 020201
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
1001 PM EDT Sat Jun 1 2024

.KEY MESSAGES...

- Scattered showers this evening into the overnight.

- Chances for showers/storms late Monday night through Tuesday.

- Cooler temperatures and occasionally wet weather late this week
  into next weekend.

&&

.UPDATE...
Issued at 1001 PM EDT Sat Jun 1 2024

Synopsis: 00z surface/composite analysis shows a somewhat
disorganized pattern across the Great Lakes and Midwest...1011mb
surface low over Illinois associated with a short wave trough.  A
cold front stretched from northern Ontario into northeast Minnesota
attached to a stronger short wave trough spinning over northwest
Ontario.  There is also a weak PV anomaly whose upward vertical
motion field was crossing Upper Michigan per WV imagery.  The short
wave trough over the mid Mississippi Valley has spread an area of
rain northeast into Lower Michigan...aided by some right entrance
region jet forcing and a surge of 1.25-1.50+ inch precipitable water
values getting transported into Lower Michigan.  Low level
frontogenesis/deformation has enhanced rainfall rates over the
southwest corner of the forecast area during the late afternoon/
early evening...LDM picked up nearly 0.80 inch of rain from
20z-00z and CAD nearly 0.25 inch with 0.25+ inch/hour rainfall
rates. To the northwest spotty rain showers occurring over
central Upper with some isolated convection moving into far
western Upper. Earlier showers over the Arrowhead of Minnesota
dissipated over western Lake Superior but pushing an undular
bore across the Keweenaw Peninsula.

Forecast Update: Bumped up QPF a bit over the southwest given what
has occurred so far though expect that rainfall rates will taper off
as forcing weakens later this evening.  Even as back edge of rain
shield pushes east fairly deep layer of moisture moves into tonight
and with some low level convergence may continue to squeeze out some
drizzle or misty light rain overnight and into Sunday morning over
far northeast Lower.  Clouds should be persistent across most of the
area into Sunday morning and should tend to mix out into a Cu deck.
Suspect that clouds over northeast Lower may be more intransigent
and have been a little more pessimistic there through the morning.
Should be a good lake breeze day with some hints for some convection
developing along colliding lake breezes in central/eastern Upper
Sunday afternoon.

&&

.SHORT TERM /THROUGH SUNDAY/...
Issued at 227 PM EDT Sat Jun 1 2024

Pattern Synopsis and Forecast:

Short wave trough and weak low pressure system currently across IL
is producing showers downstream, but largely virga across the
Northwoods. This feature will continue to move northeast into this
evening and overnight slowly moistening the atmosphere and thus
spreading showery activity across the region. By Sunday midday,
system ejects east with zonal flow and or slight height rises
engulfing the region.

Primary Forecast Concerns:

Quick moving upper level and coupled weak sfc system will move from
Illinois area into Michigan this evening and overnight. At first the
low levels of the atmosphere will be a little too dry to produce
precipitation, as shown in progged soundings, but eventually a good
chunk of northern lower will see rain showers, and steady rain for
some. Could see some modest rain amounts along and east of US-127
and south of M-72. The farther north the less precipitation with
just a few rain showers near and in the vicinity of the tip of the
mitt. Overall not all that impactful with temperatures in the 50s
tonight and light winds. Some showers activity may linger near
Alpena during the morning hours on Sunday, but generally the upper
level system ejects to the east thus ending precipitation chances.
Zonal flow/slight height rises and thus drier conditions are
expected on Sunday with seasonable temperatures as well.

&&

.LONG TERM /SUNDAY NIGHT THROUGH SATURDAY/...
Issued at 227 PM EDT Sat Jun 1 2024

Pattern Forecast: Shortwave troughing is expected to be east of the
area by early Sunday morning with shortwave ridging likely to build
across the western Great Lakes during the day Sunday. Ridging
amplifies through early this week as troughing digs upstream across
southwest Canada into the northwest third of the CONUS. By midweek,
that troughing slides overhead, potentially cutting off over the
Great Lakes region and remaining nearly stationary all the way
through next weekend. At the surface, high pressure largely expected
to be in control Sunday through Monday. Effects from upstream low
pressure perhaps felt as early as late Monday night/Tuesday with
additional periodic chances for unsettled weather through the
remainder of the forecast period as low pressure tied to the
aforementioned upper-level cutoff plagues the region.

Forecast Details: Mainly clear skies Monday night with low
temperatures largely in the upper 40s to mid-50s. Low-level
southeasterly flow aids to boost temperatures to near 80/low 80s
away from the immediate lakeshores on Monday. By Monday afternoon,
scattered convection is expected to be ongoing upstream across
eastern MN, WI and the western/central U.P. This activity will at
least initially have trouble with eastward extent given sufficiently
dry air locally; however, moisture fields to gradually increase
Monday evening, and more so Monday night - Tuesday. While
uncertainty remains with coverage of potential precip locally
(latest trends support coverage remaining pretty low), there remains
enough support to continue inherited PoPs through this time frame.
Some rumbles of thunder possible as well, especially as we get into
Tuesday afternoon. High temps Tuesday back into the 80s for many
areas with dew points creeping into the low 60s -- likely resulting
in a fairly sticky/humid day by northern MI standards.

Mid-week and onward, guidance remains fairly consistent with
troughing trekking into the region, cutting off and stalling
overhead through much of the upcoming weekend.  This ultimately
would support a rather lengthy stretch of cooler temperatures and
periodic shower chances. Coolest temperatures (60s and low 70s for
highs) progged to be Thursday through next weekend.

&&

.AVIATION /00Z TAFS THROUGH 00Z MONDAY/...
Issued at 752 PM EDT Sat Jun 1 2024

Rain band across Lower Michigan early this evening will shift
east across the state tonight and should be out of northeast
Lower prior to 12z. Rain chances should be minimal at KCIU/KPLN
and probably not much more than sprinkles at KAPN. Even as back
edge of rain shield passes moist layer remains fairly deep with
some convergence may squeeze out some drizzle at KMBL/KTVC/KAPN.
Bigger question is potential for IFR ceilings overnight with
indication of low level moistening and low clouds likely
advecting northward. Some reasonable probabilities for ceilings
dropping below 1000ft at KMBL/KTVC/KAPN (40-50 percent) in the
04z-12z window at KMBL/KTVC and after 09z at KAPN. Clouds should
mix into a Cu deck and thin out during the day Sunday though am
suspicious of how long it may take KAPN to get back to VFR
conditions (may take most of the morning under MVFR ceilings).

&&

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

&&

$$

UPDATE...JPB
SHORT TERM...JLD
LONG TERM...MJG
AVIATION...JPB