Area Forecast Discussion
Issued by NWS Wilmington, OH
FXUS61 KILN 072043
Area Forecast Discussion
National Weather Service Wilmington OH
343 PM EST Wed Dec 7 2016
As an upper level low pressure system moves eastward across
southern Canada, arctic air will invade the region over the next
few days. As the cold air flows over the Great Lakes, flurries and
snow showers will be possible on Friday, but a more significant
chance of rain and snow will move into the region for the later
half of the weekend.
.NEAR TERM /UNTIL 6 AM THURSDAY MORNING/...
A H5 low located over the wrn Great Lakes will drift ewd tonight.
South of the low, a weak trof axis will swing from the upper MS
valley and across the OH valley. Ahead of this trof, high and mid
clouds will will affect the fa tonight. The skies will become
mostly cloudy by midnight, but then as the feature works e, the
clouds will begin to decrease in the wrn sections by the end of
Temperatures overnight will fall back into the 20s, with locations
in the Whitewater and West Central Ohio reaching the lower 20s,
while the lower Scioto Valley will stay in the upper 20s.
.SHORT TERM /6 AM THURSDAY MORNING THROUGH FRIDAY NIGHT/...
On Thursday the H5 low will be in ern Canada, with a sfc
trof/arctic front working down through the lakes.
As the sunrises, there should still be some mid and high clouds,
but they should pull e by mid day. During the afternoon, the
better H8 CAA will begin to work south of the Great Lakes and a
deck of sc will gradually overrun the area. Temperatures will
struggle to warm with the increasing cloud cover and caa. Highs
will range from the mid 20s in West Central Ohio to the lower and
mid 30s in the se counties.
As Thursday night progresses, H8 temperatures will drop to -12C
and the flow will align off Lake Michigan to bring flurries to
the region. Some snow showers will be possible in West Central
Ohio closer where the better fetch off of Lake Michigan may set
up. The pattern will linger into the first part of Friday, but
then the flow begin to back off of Lake Michigan and it should
bring a gradual end to the lake effect snow activity. At this time,
I am not thinking snow accumulations will be more than a dusting
The clouds and pcpn should help the temperatures from dropping too
low. Kept lows Thursday night around 20 degrees. Highs on Friday
will work only into the upper 20s to lower 30s.
.LONG TERM /SATURDAY THROUGH TUESDAY/...
High pressure centered over the Tennessee Valley on Saturday will
provide a dry forecast over the CWA, with enough breaks in the
clouds for some sunshine during the midday and afternoon. Despite
some sunshine, it will remain cold with high temperatures likely
remaining below freezing through much of the CWA except perhaps
south of the Ohio River into northern Kentucky where high
temperatures may hit/slightly exceed the freezing mark.
High pressure shifts to the east into the middle Atlantic states
Saturday night. Result will be a south/southeast flow in the low
levels and some warm advection which will allow for clouds to roll
back in Saturday evening and for precipitation to develop well ahead
of low pressure over the central Plains.
This low is forecast to move northeast into/through the Great Lakes,
eventually allowing a cold front to pass through Sunday night or
Monday morning. Until then, confidence has increased in a period of
precipitation Saturday night into Sunday and therefore have likely
pops across the CWA. Precipitation type will likely be snow at the
onset, but with some warmer air moving in from the south on Sunday,
expect snow to mix with/change to rain particularly south of
Interstate 70. GFS is colder than the ECMWF, and therefore used a
blended approach for p-type transition Sunday. Eventually, any
lingering precipitation would change back to snow Sunday
night/Monday morning as colder air moves back in behind the cold
High pressure briefly builds in for Tuesday, but a fast-moving, weak
system may bring a chance of light precipitation by Wednesday,
although timing this far out is in question.
Below normal temperatures are expected for the long term forecast
.AVIATION /20Z WEDNESDAY THROUGH MONDAY/...
VFR conditions will prevail through the period. Mid clouds will be
prevalent for the rest of the day and most of the night. Expect
these to move off towards 12Z. May start to see some stratocumulus
develop into the KDAY area late in the TAF period. Winds will be
westerly at 10 kt or less until tomorrow when they will strengthen
with some gusts up to 20 kt possible.
OUTLOOK...MVFR ceilings possible Thursday afternoon into Friday.
MVFR/IFR ceilings and visibilities possible Sunday and Sunday