Lake Effect Snow Advisory 10, NWS Cleveland, OH

Area Forecast Discussion
National Weather Service Cleveland OH
1144 PM EST Tue Dec 13 2016

.SYNOPSIS...
A cold front will continue to move east across the local area
through this evening and will be followed by a reinforcing arctic
front on Wednesday. High pressure over the Plains will move across
the area Friday then another low will track northeast across
Michigan Saturday pulling another arctic front through the region
by Sunday.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
Update...Synoptic snow has moved out so have removed pops south
and east. Did leave a slight chance in the northeast. Although
air is very dry aloft low level winds out of the west crossing the
lake will cool through the night and by about 5am instability will
be moderate to 850mb so snow showers could develop before dawn.
Otherwise no much change for the update.

Original...Light snow continues across the area, mainly along and
west of a Upper Sandusky to Ashtabula line. Some more moderate
bands will affect areas along/southeast of Wooster to Youngstown.
Overall, total snow will be a dusting up to an inch for most
areas, with some areas further southeast seeing up to two inches.
Snow will gradually end from west to east across the area as a
cold front pushes through. Some lingering lake effect possible in
the snow belt areas overnight, but shouldn't amount to anything
over a few tenths of accumulation. With high pressure building in,
some clearing skies possible in the west overnight with some
radiational cooling dropping lows into the single digits west.
Lows generally in the teens elsewhere.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/...
Focus of the short term period continues to be bitterly cold arctic
air mass pushing across the region Wednesday night into Thursday,
with sub zero wind chills and lake effect snow the primary concerns.

Lake effect snow will ramp up across the snow belt beginning 7 PM
Wednesday night as arctic front pushes through. Initially expecting
a shore parallel band of intense snow move inland and provide a
period of heavy snowfall for much of the snow belt for a few hours.
Hi-res guidance hints at a couple primary dominant bands with
280/290 flow across the lake overnight. For now, have tried to
refine the heaviest snowfall amounts to the Geauga/Lake areas and
the higher terrain of Erie/Crawford, with general 6-12 amounts
across the snow belt. Locally higher amounts certainly possible
where the band persists, especially in the higher terrain of Geauga,
Erie and Crawford counties. Given the expected flow and some of the
hi-res guidance trends pointing to a similar band placement as the
past weekends snowfall, decided to add Cuyahoga to the lake effect
snow watch. Given many things working against highly efficient
snowfall rates, with cloud layer flow 30-35 knots and a relatively
drier arctic air mass, will continue to hold with the watch and let
the next shift assess specific needs for warnings/advisories. Either
way, expect occasional bursts of heavy snowfall reducing
visibilities and blustery conditions causing blowing snow Wednesday
night through Thursday. The intensity of the lake effect will wind
down Thursday afternoon/evening, cloud layer shear and dry air
moving into the area as high pressure builds across the area.

As far as temperatures, expecting wind chills to drop to the 5 to 15
below range Wednesday night. Wind chills will stay below zero for
most of the area Thursday with blustery conditions and high temps
remaining in the 10 to 15 degree range. Low temperatures Thursday
night will drop to near zero for much of the area away from the
lake, and although winds will be lighter, wind chill values will
again be in the 5 to 15 below range. A wind chill advisory will
likely be needed from Wednesday night through Thursday night, but
will let the next shift assess and issue closer to the time of
impact.

&&

.LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/...
High pressure over the
area will shift off to the east by late friday allowing winds to
turn more to the south and temps to moderate back closer to
normal. A low is expected to track ne near tol sat afternoon
bringing widespread precip that could start in the west by
nightfall late fri. Initially temps will be cold enough for snow
but warmer air being pulled north into the area should change the
precip to mostly rain by sat afternoon. Then as the low moves off
to the ne sat night colder air will be pulled se across the cwa
changing the precip back to snow but the precip will also start to
taper off from west to east about the same time.

Another shot of arctic air will spread over the area sunday into
monday with more lake effect shsn expected. The high associated with
the arctic air will start to shift just east of the area by late tue
which should allow temps to recover back closer to normal by tue
afternoon.

&&

.AVIATION /06Z Wednesday THROUGH Sunday/...
Low clouds will continue to produce MVFR conditions through the
rest of tonight across the region. Winds begin to increase after
12-15Z with gusts of 20 to 25 knots expected during Wednesday
afternoon into Wednesday night. Brief VFR conditions will be
possible Wednesday afternoon before quickly returning to MVFR as
low clouds build back in. Lake effect snow will begin to affect
KCLE and especially KERI after 00 to 02Z. IFR conditions will be
possible Wednesday night in any snow bands.

OUTLOOK...Non VFR lingers into Friday in the Snowbelt due to snow
showers then widespread non VFR spreads over the region Friday
night and continues until shifting back into just the Snowbelt by
late Sunday.

&&

.MARINE...
The arctic front currently pushing across the lake should have all
winds out of the west by late this evening with sca conditions from
cleveland east. Wind could increase to marginal gales by late wed as
a trough pushes into the lake and tightens the pressure gradient.
Marginal gales or high end sca conditions will likely continue until
thu night when winds diminish and start to back to the sw then south
for friday.

A low should track ne near the west tip of lake erie late sat
causing south winds to increase fri night into sat then veer to west
to nw sat night into sun with more sca conditions again likely.

&&

.CLE WATCHES/WARNINGS/ADVISORIES...
OH...Lake Effect Snow Watch from Wednesday evening through late
     Thursday night for OHZ011>014-089.
PA...Lake Effect Snow Watch from Wednesday evening through late
     Thursday night for PAZ001>003.
MARINE...Gale Warning from 3 PM Wednesday to 10 PM EST Thursday for
     LEZ061-142>149-162>169.

&&

SYNOPSIS...Greenawalt
NEAR TERM...Greenawalt/TK
SHORT TERM...Greenawalt
LONG TERM...Adams
AVIATION...Mottice
MARINE...Adams