413
FXUS63 KAPX 241916
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
316 PM EDT Sun Sep 24 2017

.NEAR TERM...(Tonight through Monday)
Issued at 312 PM EDT Sun Sep 24 2017

...Unseasonably warm weather set to continue for a few more days...

High impact weather potential...None.

Pattern synopsis/forecast...And the story remains the same, with an
unbelievably warm, record setting airmass centered across the
northern Lakes. High temperature records once again falling (now day
4 for some!) as readings push well up into the 80s and even a few
lower 90s. Sun-filled skies and increasingly dry soil conditions
only helping the warming cause. One can thank a remarkably
persistent and amplified NOAM mid and upper level flow regime for
such anomalous conditions, featuring one amped-up Eastern Great
Lakes centered ridge downstream of an equally impressive
Intermountain West centered trough (no doubt at least partially held
in place by Hurricane Maria spinning well east of Florida). Above
pattern set to become a bit more progressive and bit less amplified
in the coming days as lead piece of western energy pinwheels
northeast into the Northern Plains, forcing a slow retreat and a
notable decrease in the magnitude of that eastern ridge. Eventually,
this will bring much cooler weather and more seasonable weather to
our area. Still plenty of heat and dry conditions to be had before
this big change, and likely looking at more daily high temperature
records to be reached again on Monday.

Forecast concerns once again center solely on temperature trends, or
more precisely, just how warm to go with high temperatures on Monday.

Details: Conditions look to remain dry tonight and Monday as deep
layer subsidence continues and weak low/mid level cap remains. May
get a few more diurnally-driven cu and a bit more passing high
clouds on Monday, but overall mostly clear/sunny skies are expected.
Similar story tonight as the last several, with warm and muggy
conditions (lows only bottom out in the lower and middle 60s) and
some patchy shallow field fog.

And, just like the last several days, expect a quick diurnal
temperature response Monday under mostly sunny skies. Off the deck
thermal profiles continue to cool slightly, so expect readings to
fall just a bit short of those experienced today. Still, expected
highs in the middle 80s to near 90 will once again challenge records
for the date, and very likely at least a few records will be tied or
broken. Current high temperature records for September 25th are as
follows:

    Record (Year)
GLR   76 (1958)
TVC   89 (1908)
APN   85 (1935)
ANJ   83 (1908)
HTL   91 (1920)
PLN 80 (2007)

&&

.SHORT TERM...(Monday night through Wednesday)
Issued at 312 PM EDT Sun Sep 24 2017

...Warm stretch comes to an end; small chance of showers...

High Impact Weather Potential...None.

Pattern Synopsis/Forecast...Strong upper level ridge begins to break
down and push off to the east Monday night into Tuesday as energy
associated with western trough lifts into Ontario. A surface low
will ride northeast along a strong cold front, with the front
sweeping across northern Michigan Tuesday night into early
Wednesday. This will end the ongoing warm spell with highs on
Wednesday as much as 20 degrees cooler than Tuesday, despite being
right around normal.

Primary Forecast Concerns...Continued near-record breaking warmth on
Tuesday, followed by small chance for some much needed rain late
Tuesday into early Wednesday.

Tuesday will be the sixth and final day of this late season warm
stretch as anomalous heights and temperatures aloft gradually break
down heading into midweek. Highs will still be well above normal,
but a few degrees cooler than Monday with mid 70s to around 80 for
eastern Upper and low to mid 80s for northern Lower. Could be a
record or two in jeopardy, but not as likely as in recent days.

Tuesday`s record highs:
ANJ: 84(1908)
GLR: 80(1999)
HTL: 89(1920)
TVC: 88(1908)
APN: 88(1920)
PLN: 83(1973)

Approaching cold front late Tuesday will have a decent moisture feed
with a ribbon of PWATs in excess of 1.5 inches, but forecast
soundings show this moisture being stripped out pretty rapidly from
top down behind the front. Given the expected nocturnal passage of
the front, there will be diminishing instability for the front to
work with, with MUCAPEs a few hundred J/kg at best. Finally, fgen
lift along the front not progged to be very strong. Ingredients are
thus not looking very favorable for much of northern Michigan to see
appreciable rainfall from this event. Eastern Upper and Tip of the
Mitt are looking to see the better chance, though shower coverage
will be somewhat spotty and unlikely to produce more than a couple
tenths of an inch at best. Wouldn`t rule out a few rumbles of
thunder Tuesday night, but limited instability suggests nothing
intense. Lingering shower chances diminish rapidly after daybreak
Wednesday.

&&

.LONG TERM...(Wednesday night through Sunday)
Issued at 312 PM EDT Sun Sep 24 2017

The Tuesday-Wednesday disturbance should be clear the area by the
start of the extended period...leaving a mainly dry Thursday.
However...a clipper will roll through the great lakes Friday,
bringing a reinforcing shot of cold air and another shot at
precipitation.  I think the story to watch will be the significantly
colder air and if it will lock in long enough to initiate some lake
processes for Friday and Saturday.  My gut feeling thinks, yes.
Temperatures will moderate on Sunday with dry conditions returning
to round out the weekend.

&&

.AVIATION...(For the 18Z TAFS through 18Z Monday afternoon)
Issued at 131 PM EDT Sun Sep 24 2017

VFR conditions to continue under mostly clear skies and light
winds.

&&

.MARINE...
Issued at 312 PM EDT Sun Sep 24 2017

Weak pressure gradient and very stable over-water thermal
profiles will keep both winds and waves below headline criteria
through Tuesday. Dry and unseasonably warm weather will continue as
well.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...NONE.
LM...NONE.
LS...NONE.
&&

$$

NEAR TERM...MB
SHORT TERM...MK
LONG TERM...KB
AVIATION...MB
MARINE...MB