221
FXUS63 KGRR 240342
AFDGRR

Area Forecast Discussion
National Weather Service Grand Rapids MI
1042 PM EST Thu Jan 23 2025

.KEY MESSAGES...

- Lake Effect Winds Down Overnight

- Temps Averaging Closer to Normal After Friday, Snow Showers and
  Windy at Times

&&

.UPDATE...
Issued at 1025 PM EST Thu Jan 23 2025

Light lake effect snow continues as of 1030pm in a northwest flow.
What lake effect remains however after an eventful previous 24-36
hours is fairly tame. Visibilities at our lakeshore observation
sites are for the most part indicative of flurries. Radar returns
confirm the light nature to the snow with coverage and intensity
both on a downward trend. We dropped the Advisory earlier this
evening given current and forecast conditions at the time. We
still expect light snow to continue through the night with some
local accumulations of an inch or so possible.

Moisture depth per model data (NAM 3km in Bufkit) and the KGRR VWP
are on the shallow side with roughly 5,000 feet being the top of
clouds. Instability is quite strong with delta T`s on the order of
20-23 C tonight, but that is offset by the shallow moist layer and
more importantly increasingly anticyclonic flow. Bottom line,
light snow will continue tonight, but it will not amount to much.

Lows tonight will range from near zero up in Clare County to the
lower teens above zero along the lakeshore.

&&

.DISCUSSION...
Issued at 335 PM EST Thu Jan 23 2025

- Lake Effect Winds Down Overnight

Northwest flow lake effect snow in the wake of this morning`s
cold front has been spreading farther inland due to slight
backing of the low level flow and diurnal effects. The snow
showers now look more disorganized and less focused than earlier,
limiting accumulation rates. After sunset though the bands should
become focused to mainly near and west of 131 again as the flow
weakens. Additional (localized) accumulations of 1 to 3" are
expected tonight before the snow gradually diminishes overnight
with arrival of sfc ridging. Will keep the Winter Weather
Advisory along the lakeshore going through the evening commute.

Scattered light snow showers will probably linger into Friday
morning then diminish to flurries or end in the afternoon while
spreading back inland. Only a dusting of new snow expected but
still on the chilly side Friday with highs near 20.

- Temps Averaging Closer to Normal After Friday, Snow Showers and
  Windy at Times

For the weekend into next week the pattern looks less active and
no Arctic outbreaks are expected. The flow aloft is flat/zonal
over the weekend and next week we are still under the influence
of the nrn stream but it does not dip as far south. There`s a few
clippers in the northwest flow aloft that will impact us with
snow showers and breezy conditions at times but generally only
light accumulations are expected. The other impact will be for
temperature swings ahead and behind passing cold fronts.

The next clipper brings another southwest flow lake enhanced event
for late Friday night into Saturday, with 1-3" accums anticipated
for the same area as yesterday`s warning (north of Holland/Grand
Rapids). That is followed by westerly flow lake effect for
Saturday night into Sunday and another local inch or two. Brisk
west winds and colder temps follow for Sunday behind Saturday
night`s cold frontal passage.

A stronger clipper tracking north of Lake Superior on Monday
brings fairly strong westerly winds to the area with gusts of 35
to 40 mph possible. The cold front associated with that clipper
drops south through the area on Tuesday and may bring another
round of light snow showers then.

&&

.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 602 PM EST Thu Jan 23 2025

A mix of MVFR/VFR conditions will continue tonight with MVFR most
prevalent at our western terminals due to lingering snow showers
and low clouds overnight. Then for Friday we expect primarily VFR
conditions with lingering flurries. However some patchy MVFR will
still linger Friday due to lingering low clouds and a few light
snow showers.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until 4 AM EST Friday for LMZ844>849.

&&

$$

UPDATE...
DISCUSSION...Meade
AVIATION...Duke/Laurens