FXUS63 KAPX 181911

Area Forecast Discussion
National Weather Service Gaylord MI
311 PM EDT Sat Sep 18 2021

.NEAR TERM...(Through Tonight)
Issued at 312 PM EDT Sat Sep 18 2021

High pressure is dead overhead this afternoon, providing very
quiet wx. That will continue tonight, even as the high heads east
and we get the first inklings of low-level return flow. Airmass is
super-dry, and only cirrus expected. Also will be some patchy fog
toward dawn near inland lakes and a few other spots. Min temps
mainly low-mid 40s, closer to 50f along the coastlines.


.SHORT TERM...(Sunday through Tuesday)
Issued at 312 PM EDT Sat Sep 18 2021

...Showers and maybe some thunder with a system moving through
Monday into Tuesday...

High impact weather potential: Minimal. Small thunder chances Monday
and Tuesday

Synopsis/Pattern: The pattern across the CONUS for the second half
of the weekend will be amplifying with anomalously strong ridging
across the eastern half of the U.S. and troughing over the west.
This pattern remains progressive however, with the trough shifting
from the Rockies into the Plains Monday into Tuesday. Ahead of the
main longwave trough will be a shortwave moving up through the mid-
mississippi valley into the upper Great Lakes early Monday. This
brings our next real chance of precip in Monday and Tuesday.

Forecast/Details: On Sunday surface high pressure will be pushing
east of the area, with return southerly flow across Michigan. A
tightening pressure gradient ahead of an incoming system will keep
winds on the breezy side, with gusts between 20 and 25 mph. A sub
990mb low pushing through nrn Manitoba will draw a warm front up
over Michigan through the day, but it will be washing out in the
process, and the day looks to remain dry thanks to a fairly dry
atmosphere and weak large scale subsidence under ridging. Gulf
moisture starts to surge north Monday within the broad warm
sector...this combined with increasing dynamic lift ahead of the
trough will increase clouds and precip chances in the afternoon, and
especially overnight as better forcing moves overhead. As the
surface front moves through early Tuesday, rain chances will be at
their best, along with continued breezy conditions. Although bulk
shear will be parallel to the front, it will be a quickly-moving
system, with synoptic moisture quickly decreasing along and behind
the front...training storm and any flooding concerns remain low.
Some embedded thunder is possible, but instability looks meager at
this time.

Highs in the mid to upper 70`s on Sunday will increase to around 80
or even a couple degrees above 80 on Monday...which looks to be the
warmest day by far with at least one record (GLR) still possibly in
jeopardy of being broken....but increasing clouds and shower chances
through the afternoon may dampen this threat. Tuesday will be much
cooler behind the front.


.LONG TERM...(Tuesday night through Saturday)
Issued at 312 PM EDT Sat Sep 18 2021

High impact weather potential: Minimal

By Tuesday night the long wave trough pushes into the Great
Lakes...eventually becoming a cutoff low over the Ohio Valley on
Thursday. This then lifts up through the lower Great Lakes into
Quebec late in the week...possibly followed by another wave dropping
into the region from south-central Canada over the weekend. Guidance
varies considerably on the evolution of the upper level pattern and
associated surface features. Guidance seems to want to consolidate
on a surface low riding up through the lower Great Lakes before
following suit of the upper level system and moving into Quebec. But
the GFS is stubbornly hanging onto high pressure for part of this
timeframe. Regardless, it looks like there`s at least a chance of
showers through the end of the week and into the weekend...as well
as below normal temperatures, especially through midweek when highs
struggle to get above 60.


.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 130 PM EDT Sat Sep 18 2021

Mainly VFR.

High pressure dead overhead early this afternoon. Airmass is very
dry, with only some cirrus overhead. VFR conditions should
prevail. Did manage some fog at MBL toward daybreak this morning,
and suppose something similar is possible again late tonight.

Light winds, with onshore lake breezes this afternoon.


Issued at 312 PM EDT Sat Sep 18 2021

Light winds presently, with high pressure directly over northern
MI. The high shifts eastward, with a southerly breeze developing
for Sunday. Those breezes get a bit gusty in the afternoon, though
it appears winds/waves will stay just shy of small craft advisory





NWS APX Office Area Forecast Discussion