Area Forecast Discussion Issued by NWS Wilmington, OH
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FXUS61 KILN 171746
AFDILN
AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
146 PM EDT Sun Mar 17 2024
.SYNOPSIS...
A large scale mid level trough will dig southeast across the
Great Lakes and Ohio Valley into Monday. This scenario will
bring much colder temperatures to the region along with the
threat for a few snow showers on Monday.
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.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Skies are clear across the area this morning. We should see
some diurnal cu development later this morning into early
afternoon with skies becoming mostly cloudy across our north.
With some weak instability developing, a few rain and snow
showers may even be possible across our far north. Afternoon
highs will range from the lower 40s northwest to the lower 50s
southeast.
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.SHORT TERM /6 PM THIS EVENING THROUGH MONDAY NIGHT/...
Embedded mid level energy will continue to allow aforementioned
large scale mid level trough to pivot southeast toward our
area. We will actually see clouds decrease this
evening/overnight as diurnal instability wanes. With decoupling,
gusty winds will subside as well. As the low level flow (around
850 mb) becomes more northwest and colder, some lake effect
snow showers will develop downwind of Lake Michigan overnight. A
few of these may reach our far northwest forecast area toward
morning. Lows will drop into the mid and upper 20s.
On Monday, the mid level trough will pivot southeast across the
region. Cold northwest flow off of Lake Michigan will supply
low level moisture to much of the region. And with diurnal
heating, shallow instability will increase as the day
progresses. This will result in skies become mostly cloudy to
cloudy by the afternoon hours. And with these clouds
intersecting the favorable dendritic growth zone, some snow
showers and/or flurries will be possible. The best chance will
be downwind of Lake Michigan which favors our northern half of
the forecast area. Some light accumulations could occur briefly
on grassy/elevated surfaces, especially across the higher
terrain of west central Ohio. It will be colder than Sunday.
Highs will range from the mid 30s north to the lower 40s south.
For Monday night, a surface ridge axis will pivot southeast
into the Ohio Valley while the mid level trough axis moves east.
Low level flow will back away from Michigan, which should
eventually help reduce the cold moisture fetch into our region.
The question will be how quickly diurnally driven flurries and
snow showers will diminish from west to east during the evening.
Overnight lows will once again drop into the mid and upper 20s.
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.LONG TERM /TUESDAY THROUGH SUNDAY/...
Progressive northwesterly flow looks to be on tap for much of
the extended period. On Tuesday, a surface ridge quickly shifts
off to the east as a mid-level disturbance moves into the Great
Lakes. While precipitation should stay to our north with this
system, an increasing gradient will likely lead to gusty winds
in the afternoon.
Associated cold front will quietly move through Tuesday night
with another surface high pressure ridge building into the Ohio
Valley Wednesday into Thursday. The trend in the guidance is for
cooler conditions under the high. This trend is more pronounced
in the operational ECMWF with highs only reaching the upper 30s
to lower 40s on Thursday. Based on this, the national blend has
cooled its Thursday highs down into the 40s, and we have
followed suit in our forecast grids. Will need to continue to
keep an eye on these trends moving forward.
There is quite a bit of uncertainty in the global models as to
the approach of a potential shortwave Thursday night into Friday
morning. Have low PoPs for now due to the spread in the
guidance. Pattern may begin to shift by next weekend as mid-
level ridging attempts to build into the lower Ohio Valley in
response to a digging shortwave trough over the High Plains.
&&
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
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A diurnal cu field has developed this afternoon, especially
along and north of the I-70 corridor. It will be tough to rule
out a stray shower at the northern TAF sites through late
afternoon. Otherwise, diurnal cu will dissipate heading into
this evening with skies becoming mostly clear.
A mid level short wave will drop down across the region
through the day on Monday. This will combine with a fetch off
of Lake Michigan and some diurnal instability to result in
fairly widespread snow shower development across at least our
northern areas from late morning into the afternoon. This could
lead to some localized MVFR to IFR vsbys and cigs.
West to northwest winds with gusts to around 25 knots will be
possible this afternoon and then again late Monday morning and
into the afternoon.
OUTLOOK...No significant weather.-- End Changed Discussion --
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.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...Hickman
NEAR TERM...JGL
SHORT TERM...Hickman
LONG TERM...
AVIATION...JGL