Area Forecast Discussion Issued by NWS Gaylord, MI
000
FXUS63 KAPX 292253
AFDAPX
Area Forecast Discussion
National Weather Service Gaylord MI
653 PM EDT Wed Mar 29 2023
.NEAR TERM...(Through Tonight)
Issued at 355 PM EDT Wed Mar 29 2023
High Impact Weather Potential...briefly heavy lake effect snow
showers and low visibilities into early evening.
1007mb (and deepening) low pressure is in w central Quebec, moving
e. High pressure is in sw MN. This high will build ese, across
southern lower MI and toward PA tonight. Winds will back as this
occurs, toward wnw this evening and wsw by morning. 850mb cold
advection ends this evening, with warm advection overnight. 850mb
temps rebound to around -10C over nw lower MI by morning. This is
not something one would normally be excited about in late
March...but it is what it is.
With loss of diurnal "heating" and it`s contribution to
instability, SHSN intensity will wane somewhat this evening.
Winds will also relax with less vertical mixing, but mainly as the
pressure gradient relaxes. Near whiteout conditions have been
noted at times in open areas of Chippewa Co with falling and
blowing snow, but that should be much improved this evening.
Inversion heights at Sault MI hold at 6k ft thru the evening, then
crash overnight with the backing winds and developing warm
advection. Will hold onto higher pops this evening, especially in
Chippewa Co but even in far northern lower MI. But backing
winds/warm advection/crashing inversion heights will wipe out lake
effect snow overnight. And skies should become mostly clear
across the area by daybreak.
Min temps will be chilly, well into the teens in the interior, and
near 20f along the nw lower MI coast. Trout Lk and nearby spots
in eastern upper MI will likely dip to 5 to 10f above.
&&
.SHORT TERM...(Thursday through Saturday)
Issued at 355 PM EDT Wed Mar 29 2023
High Impact Weather Potential: Burst of snow Thursday night turns to
moderate to heavy rain through Friday night. This rain will produce
ponding of water in low laying areas and on roadways. Also a chance
of some freezing rain Thursday night over eastern upper and inland
areas of northern lower Michigan. Heavy snow possible Friday night
into Saturday across eastern upper with possible blizzard conditions.
This forecast period begins with an area of high pressure centered
over the Ohio River Valley and ridging through the Great Lakes
region. This high pressure will produce a precipitation-free day as
as the ridge remains overhead but moving eastward. As this
high pressure moves off to the east winds back to southwesterly.
These southwesterly winds will advect Gulf moisture northward and
combine with some remnant Pacific moisture from a decaying area of
low pressure over the Rockies. An area of low pressure redevelops on
the lee side of the Rockies and treks through the Straits area late
Friday night. Precipitation will begin as snow on the initial WAA
surge Thursday night/early Friday morning with 1-3 inches possible
(mainly over eastern upper and portions of northeast lower) before
the mix and changeover to rain occurs after sunrise Friday morning.
There will be the possibility of some freezing rain late Thursday
night into Friday morning with forecast soundings showing a warm
nose above the sub-freezing surface of eastern upper and northeast
lower. Most locations should see around a half inch to three
quarters of an inch of QPF by Friday evening. Forecast soundings
have PWATs nearing 1.00" late Friday night. There is also a couple
hundred Joules of elevated CAPE progged, especially south of the M-
72 corridor, which could produce some heavier showers (maybe even a
rumble of thunder?) Friday evening through Friday night, hence
localized higher amounts will be possible under any convection that
does happen to develop. Storm total QPF is forecast between 1.00" to
nearly 2.50" by Saturday evening. The highest amounts will be along
the Lake Michigan shoreline of northwest lower Michigan and all of
the eastern upper peninsula. The heaviest snow will be across
eastern upper where 6-12 inches of snow will fall late Friday night
through Saturday afternoon. With winds forecast to gust 35-45mph,
wouldn`t doubt it if blizzard conditions were realized for at least
a few hours, if not longer, during this timeframe. Evaporative
cooling may drag the snow line a bit farther south, especially if
any convective elements develop.
Winds will become southwesterly by the early morning hours of
Thursday. Winds then back further throughout Thursday night and
into Friday morning to become southeasterly ahead of the approaching
warm front. Winds behind this system will be northwesterly with wind
gusts up to 45-55mph...especially along the Great Lakes shorelines.
Thursday will see highs in the mid 30s to mid 40s on the
southwesterly winds, while Friday hits the low 40s across eastern
upper Michigan and northern lower sees the upper 40s to mid 50s with
the warmest temperatures near the Saginaw Bay area. Saturday will be
cooler again with highs only in the low 30s to low 40s (eastern
upper and the tip of the mitt the colder areas).
.LONG TERM...(Saturday night through Wednesday)
Issued at 355 PM EDT Wed Mar 29 2023
High Impact Weather Potential: Minimal at this time.
High pressure will provide precipitation-free weather through much
of Sunday, although some WAA precipitation may begin late Sunday
through the first half of the next work week. This precipitation
should be mostly in the form of rain, although with the colder
temperatures during the overnight hours there may be a mix or
complete changeover to snow. This is still a bit far out and will be
changed/updated when needed. With the southerly flow it appears that
there may be temperatures in the mid 40s to mid 50s to begin the
next work week as well.
&&
.AVIATION...(For the 00Z TAFS through 00Z Thursday evening)
Issued at 649 PM EDT Wed Mar 29 2023
Just a few lingering lake effect snow showers early this evening,
primarily impacting CIU with some occasional IFR/MVFR conditions.
Prevailing conditions improve to VFR area-wide this evening into
the overnight hours, and for much of Thursday. West-northwest
winds this evening slowly back more southwesterly by Thursday
morning...becoming occasionally breezy again at times by Thursday
afternoon.
&&
.MARINE...
Issued at 355 PM EDT Wed Mar 29 2023
Low pressure in w central Quebec will move away from the region. Nw
winds will slowly become less gusty into this evening and tonight.
Winds will eventually back toward the sw by morning, and remain
there into Thursday. Northerly gales (at least) are looking
increasingly likely on Sunday, after strong low pressure passes by
the area. A few storm force gusts are possible.
&&
.APX WATCHES/WARNINGS/ADVISORIES...
MI...NONE.
LH...Small Craft Advisory until 10 PM EDT this evening for LHZ345.
Gale Warning until 8 PM EDT this evening for LHZ346>348.
Small Craft Advisory until 2 AM EDT Thursday for LHZ349.
LM...Small Craft Advisory until 10 PM EDT this evening for LMZ323-341-
342-344>346.
LS...Gale Warning until 8 PM EDT this evening for LSZ321-322.
&&
$$
NEAR TERM...JZ
SHORT TERM...TJL
LONG TERM...TJL
AVIATION...MJG
MARINE...JZ