Area Forecast Discussion
Issued by NWS Cleveland, OH
FXUS61 KCLE 080934
Area Forecast Discussion
National Weather Service Cleveland OH
434 AM EST Thu Dec 8 2016
Deep low pressure near James Bay will drift east to northern
Quebec. A trough of low pressure will extend southwest across the
central Great Lakes. The trough will drop southeast and cross Lake
Erie tonight. Saturday high pressure will build into the region
from the central plains.
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Surface trough was located over the upper great lakes this
morning as deep low pressure continues a slow move across northern
Quebec. 8H temperatures already down to about -8C this morning
and should slowly chill from here. So this is already cold enough
to get all snow where lift and convergence are the strongest. This
will occur over Lake Erie through the morning with it being
directed into Western NY on a southwesterly wind. This band of
snow will slowly edge toward the lakeshore through the afternoon
and will likely get into Erie PA by mid afternoon. As the surface
trough passes late afternoon/early this evening the snow will move
inland. This is when the significant accumulations will begin.
It will become very cold aloft through this afternoon. So with
the steep lapse rates over the warm waters of Lake Erie there
could be some thunder. This will of course increase snowfall rates
and may produce snowfall rates in excess of 2 inches per hour.
Highs today will generally be in the upper 20s to around 30 but it
will feel colder as the day progresses. Gusty west winds will
make it feel like it is in the teens.
.SHORT TERM /6 PM THIS EVENING THROUGH SATURDAY NIGHT/...
Moderate to high instability over the warm waters of Lake Erie
will develop quickly this evening as the surface trough passes. As
the winds turn more to the northwest this will push the snowfall
inland. Have decided to grab a couple more counties for the LES
warning where the higher terrain will assist in significant
accumulations. So with that said we have added Geauga and Inland
Ashtabula counties beginning at 6 pm. Heaviest accumulations will
likely occur after midnight tonight into Friday. Refer to our
snowfall graphic on our webpage and on facebook/twitter.
We will need to monitor the remainder of the watch very closely
and will at least need an LES advisory. While we do expect to see
some thunder snow develop we are reluctant to add the lakeshore to
the warnings. Want to see the thunder develop over the lake this
afternoon to build our confidence.
The lake effect snows will continue through Friday on a
northwesterly flow. However these steering winds will shift back
to the west Friday night into Saturday with the lake effect snow
shifting back up the shoreline. The remaining bands of snow will
likely shift back into western NY at some point on Saturday.
Warm advection develops Saturday night ahead of the next area of
low pressure and will likely produce some light snow for the
entire region. Looks like light amounts but could be a couple
It will feel winterlike into the weekend. Highs will be in the 20
to around 30. A few teens will be possible each night...especiallywhere
any breaks in the cloud cover can occur. Winds will make it feel
.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
The models show a low moving ne across the area sun night thru
monday with widespread but generally light precip with the type of
precip being the issue. Will stay with likely or better pops and
mainly snow but by sometime monday at least the se half of the cwa
could see chg to rain if the low does take a more nw track.
Another push of arctic air is expected to arrive about tue night and
this batch will likely be even colder than the current one. More
lake effect snow showers will occur.
.AVIATION /06Z Thursday THROUGH Monday/...
Still not much going on with mid level cigs over the area. Will
start to see cigs lower overnight as colder air begins to move
in. Lake effect bands will develop in the WSW flow and initially
stay north of the area. The band will begin to impact ERI this
afternoon with snow showers spreading across the remainder of the
area toward evening as an upper trough crosses the region. Cigs
should stay VFR through late Thursday expect at ERI. Will take
cigs to MVFR during the evening as the trough rotates through the
area. Westerly winds will gradually increase overnight with gusts
to 25 knots by morning and gusts to 30 knots during the day.
OUTLOOK...Arctic front will move through tomorrow. Lake Effect
snow becomes more widespread and intense Thursday night and will
continue into Saturday, especially across the snowbelt east of
SCA conditions expected into fri morning for all of the lake then
continuing east 2/3 into saturday until high pressure moves up the
ohio valley to lessen the flow. Winds back to the south by sunday
then more in question from sunday evening thru monday do to model
differences so will stay with superblend progs for this time period
as a low should track ne near the lake monday.
The moderate west winds could push water levels in the western basin
down near the critical mark for safe navigation later today into
OH...Lake Effect Snow Watch from 3 PM EST this afternoon through
Saturday morning for OHZ012-089.
Lake Effect Snow Warning from 6 PM this evening to 4 PM EST
Saturday for OHZ013-014.
Lake Effect Snow Watch from this evening through Saturday
morning for OHZ011.
PA...Lake Effect Snow Warning from noon today to 4 PM EST Saturday
MARINE...Small Craft Advisory until 4 PM EST Saturday for LEZ146>149.
Small Craft Advisory until 4 PM EST Friday for LEZ142>145.