National Weather Service - Area Forecast Discussion

FXUS63 KAPX 021339

Area Forecast Discussion
National Weather Service Gaylord MI
939 AM EDT Fri Jun 2 2023

Issued at 939 AM EDT Fri Jun 2 2023

Surface high pressure is extending ridging southward into MI this
morning. What synoptic wind there is, is from the east to ne. There
is thin cirrus across the area, and some bubbly accas in the far
sw (enough to make that area mostly cloudy). Temps are climbing
into the 70s at this hour.

There are enough clouds in the sw to hold max temps back just a
smidge, and sw of TVC will tweak those slightly lower. Still
toasty today though.

Deep convection in northern lower MI will be greatly hindered by
an inability to maintain low-level moisture. 12Z APX sounding had
a PWAT of 0.56"; very dry for an airmass that warm. Dew points
will tend to mix out with stronger heating today, and like a
mostly dry forecast south of the bridge.

However, near-term models consistently support somewhat better
moisture in eastern upper MI and nearby portions of Ontario.
MlCape values could reach 5000-1k j/kg just ne of the Sault. Lake
breezes could generate convection in this area this afternoon and
early evening (noting that western upper MI has been able to
sustain TSRA activity this morning). This area already had a
chance of precip in the grids this evening; will add small pops
to eastern upper MI from mid-afternoon on. Highest pops will be
near the St Marys River system.


.NEAR TERM...(Today through Tonight)
Issued at 321 AM EDT Fri Jun 2 2023

High Impact Weather Potential: Minimal.

Pattern Synopsis/Forecast: Upper-level ridging remains in place
across the nation`s midsection early this morning with the embedded
ridge axis essentially running from the Arklatex region northward
through the upper MS Valley/Great Lakes into Ontario. Very little
change to the upper-level pattern through the near-term forecast
period. Stagnant surface pattern continues as well with high
pressure sagging in overhead from the north. However, by this
evening, a moisture-starved backdoor cold front is expected to
approach the eastern UP from the northeast, slowly traversing the
forecast area tonight.

Primary Forecast Concerns: Temperatures and low chances for an
isolated shower or thunderstorm.

Another hot day on tap across northern Michigan with a couple of
daily high temp records likely to be broken once again. A list of
those existing records is below. Highs generally ranging from the
upper 80s to mid-90s, of course cooler near the immediate
lakeshores. Light winds today will promote inland penetrating lake
breezes this afternoon with corresponding pop up shower/storm
chances looking incredibly low, despite increasing afternoon
instability. Will hold off on including any mentionable PoPs across
southwestern areas, but it`ll be worth monitoring as we head through
this afternoon.

Low PoPs do enter the forecast for eastern portions of Chippewa and
Mackinac counties near and just after 00z in response to the
aforementioned cold front beginning to make progress into the
forecast area from the northeast. Those isolated to scattered
shower/storm chances diminish pretty quickly through the evening as
any diurnally driven instability diminishes, and forcing/moisture
associated with the front is limited (at best). Overnight lows only
falling to the mid-upper 50s for most.

Existing high temperature records for today, June 2nd:

    Location     |   Temp F (Year)

Alpena           |     92 (2020)
Houghton Lake    |     97 (1934)
Sault Ste Marie  |     88 (1919)
Traverse City    |     99 (1934)
Gaylord          |     87 (2020)
Pellston         |     90 (1963)


.SHORT TERM...(Saturday through Sunday)
Issued at 321 AM EDT Fri Jun 2 2023

HIGH IMPACT WEATHER POTENTIAL: Minimal, but will have to watch fire
weather concerns for Sunday...


Anomalous 586dm 500mb ridge continues to retrograde across the Great
Lakes, as troughing sinks through Quebec. Longwave troughing across
the western a handful of shortwaves transition through the
flow (PacNW, Desert SW, Colorado). A handful of other niblets
traversing the flow over the ridge...with one actually just to our
northwest as of 3z...and one subtle one fading just to our southwest
as a plume of deeper subsidence overspreads the southern half of
Lower MI. Meanwhile...anomalous troughing maintains control over the
Gulf of Mexico/Florida. Even so... moist return flow holds on across
the center of the country...also spreading out along the zonal-ish
BCZ juuuust north of us for now...though 1032mb surface high over
Hudson Bay, behind this BCZ, has much drier air with it. Surface
temps in the upper 80s and low 90s continue...with 850mb temps
holding on in the upper teens (and per the 0z/02 APX sounding...we
are mixing deeper than 850). Upstream...troughing holds on in the
Gulf of a 140+kt East Asian jet holds on across
(appropriately) eastern Mawar recurves and begins the
process of absorbing into the flow.

Upper ridge to continue to surface high settles into
eastern Canada behind the downstream trough. A subtle PV anomaly
drifts down through the state a broad area of low
pressure develops to our north, in response to another bit of energy
diving down the downstream side of the ridge into eastern Canada.
This should continue to force ridging westward into the center of
the upstream troughing pivots onto the western coast
of Canada. While there is still some uncertainty in the strength of
the second niblet diving down into eastern Canada Sunday/Sunday
night and, and the strong surface high in its wake, bear
watching for the start of the extended, for early next week.

PRIMARY FORECAST CONCERNS: Precip chances...Dewpoints...

Moisture plume along the BCZ to our north should rotate in late
Friday night into Saturday morning. There is still some uncertainty
in timing of this though, which will impact the potential for
precip... A more progressive solution would sweep much of the better
moisture out of here before the best diurnal heating is able to take
place, while a slower solution would keep it over more of the CWA
into the afternoon during peak heating. Either way, looking at a
decent potential for activity over NW Lower (particularly south of M-
32/M-72?) this area should be favored for more aggressive
convergence between the potential lake breeze...and increasingly
north/northeasterly flow. Will be something to keep an eye on for
sure. Would not be surprised if we ended up somewhat similar to
Wednesday, with a pretty decent smattering of storms...noting that
we may have some (albeit weak) PVA into the region with a subtle
niblet in the flow...along with some potential for instability with
surface heating (perhaps several hundred joules of CAPE?).
Additionally...if we do manage to get some deeper convection, will
certainly have to keep an eye out for some small hail, similar to
Wednesday. It could be a bit of a struggle, though...if we end up
with enough mid/high clouds to keep us from heating too quickly
while the deepest moisture is around...but certainly something to
watch out for, particularly if you have any outdoor plans for

By Sunday night...that next BCZ and associated moisture plume will
be slipping into the region from the the niblet drops
through Hudson Bay. This should result in some weak theta-e
advection along/ahead of the front...though it should be contending
with a pretty dry antecedent air mass over our region from Saturday
night into Sunday, which may (at least initially) keep things from
reaching the ground. Best chance of anything reaching the ground
Sunday night would be across the eastern UP, closer to the boundary
and deeper moisture. There is some uncertainty in how quickly this
moves will be something to keep an eye on...but I do think
it will be a little slower than some guidance suggests. Not out of
the realm of possibilities that parts of northwest Lower/eastern
Upper could have a brush with some warm advection precip along an
approaching warm front Sunday night, but we`ll see.

I expect things will remain reasonably warm this weekend...given
that 850mb temps will still remain supportive of highs in the 80s,
especially where downsloping will be involved (i.e., NW Lower, given
easterly flow)...though a few more 70s could creep in Sunday,
perhaps, as we shouldn`t be quite as warm as we have been. This
being said...the dryness will be something to watch out for,
particularly Sunday afternoon across the SE CWA. Guidance continues
to signal a plume of dry air pivoting into that portion of the area
as the somewhat squashed surface high slips into the region. Would
not be out of the question to see dewpoints in the upper 30s F down
that way, which, given the still warm weather around...suggests
potential for critical RHs yet again. This does not bode well going
into a days 4-7 period likely marked by additional cool, dry,
northerly flow out of Canada (see below).

.LONG TERM...(Sunday night through Thursday)
Issued at 321 AM EDT Fri Jun 2 2023

HIGH IMPACT WEATHER POTENTIAL: Minimal for now...watching for
continued dryness...and cooler temperatures...


By Monday...guidance points toward the ridge over the center of the
continent...with energy over western and eastern Canada on either
side of it...and even in the southern portion of the flow...some
energy punching into the SoCal region. For now...looks as though the
energy dropping out of eastern Canada will have some
potency...though there is yet a fair bit of uncertainty in how it
evolves troughing over the northeast US...and the resultant location
of the surface responses as a result. Even so...potency of this
trough (potentially sub 560dm at 500mb over New England?) suggests
strengthening of the BCZ along this side of the ridge...and
subsequently, potential for stronger flow (aloft, and perhaps at the
surface as well) than we`ve seen in a while...particularly while the
surface high remains parked to our north. Looking at pretty decent
signals for cold advection into midweek, with some uncertainty in
how yet another niblet diving nearly due south out of Hudson Bay
evolves as it approaches our region for the latter half of the
week...potentially related to how the system over western Canada
moves through the flow. Either way...this idea signals a return to
cooler air for the Great Lakes going into the middle and latter half
of next week especially. Additionally...this also has signs of
continued dryness, as the stronger northerly/northeasterly flow
would be advecting continental Polar (i.e., cool and dry) air out of
Canada. Will be something to keep an eye on as we go forward,
particularly given how dry we have been thus far.


.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 601 AM EDT Fri Jun 2 2023

VFR conditions will continue through the period with just passing
high clouds today, along with limited afternoon high based cu
development.  Any attendant showers look to be few and far between
this afternoon (if at all), and not worthy of any specific
mention in the forecast. Light winds, with afternoon lake breeze
development expected.


Issued at 321 AM EDT Fri Jun 2 2023

Overall light wind fields expected to continue today with onshore
lake breezes becoming likely once again this afternoon. While sub-
advisory conditions are anticipated to continue through tonight,
it`s not entirely out of the question that winds/waves approach
advisory levels Saturday, particularly near Saginaw Bay.





NWS APX Office Area Forecast Discussion