498
FXUS63 KAPX 260345
AFDAPX

Area Forecast Discussion
National Weather Service Gaylord MI
1145 PM EDT Tue Mar 25 2025

.KEY MESSAGES...

- Snow showers diminishing; seasonably cold tonight.

- Watching for impactful wintry mix and potential widespread
  icing this weekend.

&&

.UPDATE...
Issued at 1004 PM EDT Tue Mar 25 2025

Approach of upstream ridge axis and the arrival of drier low
level air are working to slowly diminish ongoing lake effect
snow shower activity late this evening. Upstream radars KMQT and
KGRB are generally void of returns attm...and our latest KAPX
base ref loop is showing a gradual diminish in both areal
coverage and intensity of snow showers. This downward trend will
continue thru the remainder of tonight. Have made some minor
timing adjustments to POPs. Expect another cold night across our
Northwoods with overnight lows dropping mainly into the teens.

&&

.SHORT TERM /THROUGH WEDNESDAY/...
Issued at 248 PM EDT Tue Mar 25 2025

Pattern Synopsis and Forecast:

Short wave trough axis shifts to the east/southeast overnight,
resulting in diminishment/transportation of most snow showers
out of the area. Secondary little vort rotating around the
center of the shortwave/upper low center takes a swipe at the
shoreline of northeast lower MI, with lingering snow showers
across this area as a result. Dry northwest flow takes hold into
Wednesday with surface high pressure sliding to the south and
thus, lack of precipitation.


Primary Forecast Concerns:

Lingering snow showers:

Snow showers will linger tonight, mainly across the coast of
northeast lower MI, and perhaps pockets of convective lake
effect snow showers ~downwind of Grand Traverse Bay and
vicinity (this evening/early overnight). Not much in the way of
additional accumulation though but drops in visibility at times.
Precipitation chances will start to diminish through the night
as drier air works in from the west and the mid level lift
evacuates to the east.

Cold temps tonight:

Decreasing precipitation and cloud cover is anticipated through the
night, most persistently across the E UP. Fcst soundings suggest
this region will be most likely to decouple completely as well,
leading to some confidence that low teens to single digits will be
possible. Guidance does not want to scour clouds out as quickly
across northern lower, and so little less certain across this
area. In any event, 10s and 20s likely.

Wednesday:

Clouds decrease for most on Wednesday, with sunshine returning and
temperatures rising above freezing. Late March sun should warm
to near/above 40 in spots, although some guidance was a little
cooler. Overall though, should be an uneventful day.

&&

.LONG TERM /WEDNESDAY NIGHT THROUGH TUESDAY/...
Issued at 248 PM EDT Tue Mar 25 2025

Pattern Synopsis:

Pacific midlevel blocking pattern with Large scale low pressure over
the Pacific-NW and troughing over the northeastern U.S. Midlevel
troughing in the middle continues to build subsistence over the
central U.S until troughing advects northward, leaving a more zonal
flow pattern over the Great Lakes region around the Friday
timeframe.

Moisture advection in the mid levels from the west coast
atmospheric river will be ejected into the northern plains combined
with low level southerly moisture advection, leading to an extremely
efficient saturated environment across the Northwoods this weekend.
Precipitation will begin as early as Friday as a frontal boundary
stalls over the northern CONUS. What complicates the forecast is
high pressure from the north will fight the warm/moist airmass right
over the Great Lakes region... resulting in multiple precip types to
linger across the CWA through Sunday. Guidance continues to depict
icing for northern lower while areas along the U.P will have less of
a warm influence leading to more sleet and snow. Precipitation
continues through Sunday as the low pressure system finally departs
to the east. Subsidence from the north finally departs moisture and
returns cold, dry air to finish off the forecast period.
Unfortunately, high temperatures remain around freezing this Monday
and Tuesday giving little to no relief after a long lived mixed
precip event across northern Michigan.

Primary Forecast Concerns/Key Messages:

Focus remains on the busy travel weekend for the northwoods due to
spring break coming to an end for many. Conditions do not represent
spring however as a stationary front stalls over the Upper Great
Lakes delivering precip as early as Friday and continuing until
surface low pressure departs on Sunday. A low level jet develops
this Thursday and advects warm/moist air into the region...
delivering the perfect warm nose to create a freezing rain event
Friday night through. Conditions remain a little colder and have
less of a southerly influence across the U.P, leaning towards more
sleet and snow at this time, but will still likely lead to poor
roadway conditions this weekend.

From a climatological standpoint... accumulating icing events are
pretty rare for Northern Michigan, and depending on the amount of
influence from northerly high pressure more snow may become favored
with future guidance. We will continue to monitor this event as it
evolves, but with ensembles remaining relatively locked in with QPF
totals of 1.5" to 2" over the entire weekend it is definitely
warranted to keep focus on this set up and its potential impacts to
travel.

&&

.AVIATION /06Z TAFS THROUGH 06Z THURSDAY/...
Issued at 1145 PM EDT Tue Mar 25 2025

Sharp upper level troughing will continue to exit eastward away
from Michigan tonight...bringing a gradual close to residual
lake effect snow showers. Upstream ridge axis will build over
Michigan Wednesday...resulting in dry wx and clearing skies.
MVFR/IFR conditions will improve to VFR late tonight and
Wednesday. Surface winds will remain from the NW at around 10
kts.

&&

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

&&

$$

UPDATE...MLR
SHORT TERM...JLD
LONG TERM...SJC
AVIATION...MLR

NWS APX Office Area Forecast Discussion