Area Forecast Discussion


946 
FXUS61 KCLE 192346
AFDCLE
Area Forecast Discussion
National Weather Service Cleveland OH
646 PM EST Sat Jan 19 2019
.SYNOPSIS...
A strong low pressure in the Mid-Mississippi Valley will track 
to eastern Kentucky this evening and spread significant 
snowfall to much of the area. The low pressure area will move to
New Jersey by Sunday morning as arctic high pressure begins to 
build into the region in the wake of the storm.
&&
.NEAR TERM /THROUGH SUNDAY NIGHT/...
Widespread moderate to heavy snow continues over the forecast
area this evening. Hourly snow accumulation rates of 0.5 to 1.0
inch are common across most of the forecast area. As the low 
deepens and the 850mb low moves south of the forecast area 
overnight, moderate to heavy snow is likely for the eastern 
2/3's of the area. The back edge of the snow is approaching the 
Toledo metro area. Northeast winds with gusts to 35 mph are
occurring and expected to continue overnight. Short term models
indicate the back edge of the snow will reach the Toledo metro 
area around 10pm and slowly work east from there. The current 
forecast appears to be in line with ongoing conditions. I will 
make no adjustments at this time but will closely monitor the 
progress of the storm over the next several hours.
Previous Discussion...
The only forecast changes with this afternoon 
update is the addition of a wintry mix south of Highway 30. The 
warm nose layer or warm air aloft came in a little further than 
previously forecast. We have freezing rain and sleet mixing in 
for our central Ohio counties with temperatures in the upper 20s
to around 30. We will likely see a light glaze of ice on 
objects and some minor sleet accumulations before the wintry mix
changes back over to all heavy snow early this evening. We 
think it will be all snow again between 6 pm and 8 pm this 
evening.
Given that the wintry mix transition line shifted a little
further north, we also shifted the highest storm totals a little
northward as well. They will be between I-80/90 and Highway 30.
See the latest SPC mesoscale discussion regarding heavy snowfall
rates for the rest of the afternoon into this evening. We will
see 1 to 1.5 inch per hour rates at times under the heavier
snowbands and visibilities between 1/2 a mile to a 1/4 of a mile
through much of the evening and overnight. As the surface low
pressure is deepening and move through the Ohio River Valley, we
will see our winds locally become stronger. Northeast to North
winds will be 20 to 30 mph with gusts up to 40 mph tonight.
Blowing snow will be likely this evening through Sunday morning. 
We will likely end up with a storm total of 5 to 8 inches for 
portions of northwest Ohio. The rest of northern Ohio will see 6
to 10 inches storm total with some isolated locations seeing up
to a foot of snow by early Sunday morning. Northwest 
Pennsylvania will end up with 10 to 12 inches of snow as well.
Temperatures will fall tonight and during the day on Sunday. We
will also see our snow to liquid ratios increase tonight into
Sunday as the Arctic airmass starts to move in. We started out
using 12 to 1 for the first half of the storm and 15 to 1 ratio
by Sunday morning.
The storm will begin to pull away Sunday morning. We have push
back the snow ending from west to east for a few hours. We will
likely see moderate to heavy snow through 4 am or so and slowly
tapered off. Strong northerly winds tomorrow and Arctic air will
turn on the Lake Effect Snow machine from Lake Huron and Lake
Erie. Models are in better agreement for a band of snow to
develop down into northwest Ohio near the islands by Sunday 
afternoon. This band will gradually move eastward as the winds 
turn more northwesterly Sunday night into Monday. We do expect
additional 3 to 5 inches for fluffy Lake Effect snow for areas 
that stay under the persistent bands across the primary and 
secondary Snowbelt. Looking at the lower atmospheric profile and
BUFkit, the moisture and signal is a little better and more 
confidence for LES development. Temperatures will be frigid by 
Monday morning with areas away from the lake below zero and wind
chills -10F to -20F.
&&
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
Lingering lake effect snow will continue to impact the snowbelt
in NE Ohio and possibly NW PA through about noon on Monday. 
Little accumulation is expected during this time.
The big story for Monday will be the cold temperatures expected to 
impact the region. Northwest and north central Ohio can expect to 
remain in the upper single digits...where just east of there will 
warm generally into the mid teens. This in combination with light to 
moderate northwest winds will result in wind chill values in the -10 
to -20 range. The cold temperatures continue into Monday night and 
Tuesday morning where locations a bit more inland from the lake 
could see temperatures fall to near zero. 
Otherwise...temperatures begin to warm Tuesday into Wednesday as an 
upper trough moves east toward Ohio. We will see daytime high 
temperatures warm into the mid 30s on Tuesday and into possibly the 
mid 40s by Wednesday. The next shot of precipitation moves into 
western Ohio Tuesday afternoon spreading southeast through the rest 
of the area by Tuesday night into Wednesday morning. With the warmer 
temperatures...we are going to have a bit of a mixed bag of 
precipitation...starting off as snow...transitioning to rain by 
Tuesday night...back to snow by Wednesday afternoon. There is the 
possibility of freezing rain generally across the southern and 
eastern portion of the forecast area late Wednesday afternoon into 
Wednesday night.
&&
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
By Thursday morning we are expecting another cooling trend...with 
precipitation back to all snow. Starting Thursday night...a series 
of upper level shortwaves will pass east through the area bringing a 
chance of snow to the area. Details will be worked out as we near 
this part of the forecast. Either way...the entire forecast calls 
for mostly unsettled weather through the end of next week.
&&
.AVIATION /00Z Sunday THROUGH Thursday/...
Widespread moderate to heavy snow will continue to move over
the TAF locations this evening. Some patches of freezing rain
are mixing with the snow over CAK and YNG. This may continue for
another few hours before the transition to all snow. Ceilings
will remain IFR for most locations overnight. The western TAF
sites of TOL and FDY will start to improve after 03Z as the snow
ends in this area. Northeast winds will continue overnight and
gradually become northerly. Wind gusts around 30 knots will be
common especially for the northern TAF locations. 
OUTLOOK...Non-VFR in snow at times across the snowbelt on
Sunday through Monday. Non-VFR possible Wednesday.
&&
.MARINE...
Strong northeasterly winds will develop today with a strong pressure 
gradient as low pressure tracks across the Ohio Valley and high 
pressure remains positioned across the northern lakes and northern 
Plains. Winds are expected to peak at 35 knot Gales tonight, 
diminishing for Sunday. A small craft advisory will surely follow 
the Gale Warning and likely last through Sunday night. Air 
temperatures are expected to plummet through the teens Sunday and 
into the single digits for Sunday night. Heavy freezing spray is 
still a concern and a warning may be needed for extreme spray with 
the juxtaposition of temperatures getting below about 12 and winds 
still around 30 knots Sunday afternoon/evening. High pressure will 
pass across the lake Monday quieting the lake but also allowing for 
the possibility of a fast freeze on the western basin. See the Ice 
Outlook/Marine Weather Statement for a possible Ice Advisory. South 
through southwest winds increase on the lake going into Wednesday 
with a cold front crossing the lake early Wednesday. This will 
likely be another small craft advisory situation.
&&
.CLE WATCHES/WARNINGS/ADVISORIES...
OH...Winter Storm Warning until 4 AM EST Monday for OHZ010>014-
     020>023-089.
     Winter Storm Warning until 10 AM EST Sunday for OHZ009-017>019-
     027>033-036>038-047.
     Lakeshore Flood Warning until 7 AM EST Sunday for OHZ003-007-
     009.
     Winter Storm Warning until 4 AM EST Sunday for OHZ003-006>008.
PA...Winter Storm Warning until 4 AM EST Monday for PAZ001>003.
MARINE...Gale Warning until 4 AM EST Sunday for LEZ142>149-162>169.
&&
$$
SYNOPSIS...Griffin
NEAR TERM...Garnet/Griffin
SHORT TERM...Riley
LONG TERM...Riley
AVIATION...Garnet
MARINE...Riley