611
FXUS61 KILN 170007
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
707 PM EST Tue Dec 16 2025

.SYNOPSIS...
Southerly flow allows for a warming trend as the week progresses.
Temperatures will rise back above normal on Thursday, but this will
be accompanied by rain ahead of an approaching cold front. High
pressure will bring dry weather Friday and cooler temperatures. The
cool down will be brief with temperatures warming above normal for
the weekend. A low chance of rain returns late in the weekend.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
Southerly flow persists through the afternoon and overnight hours.
Clouds overnight, when combined with this southerly flow and weak
WAA, will allow temperatures to remain steady or slightly above
freezing for many locations. The winds overnight remain around 10-15
mph since the Ohio Valley is squeezed between a low passing to the
north and high pressure to the southeast. A LLJ aloft should remain
firmly above the low level temperature inversion.

&&

.SHORT TERM /WEDNESDAY NIGHT/...
Southerly flow weakens a bit on Wednesday since the pressure
gradient over the area weakens. Forecast highs range from the upper
30s north of I-70 to the middle 40s south of the Ohio River under a
mix of sun and clouds.

Southerly flow increases on Wednesday night when the pressure
gradient strengthens southeast of a deep, broad low in the Upper
Mississippi River Valley. A LLJ moves in from the west after 0800z
which could start to support low end shower chances by daybreak.
Warm advection and moisture increases actually remain modest most of
the night before increasing more in the morning hours. Temperatures
likely remain above freezing for many locations.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
Strong WAA will be underway early Thursday with the approach of a
digging trof into the Midwest. Deep-layer SW flow will become
established in the OH Vly, with temps topping out in the 50s area-
wide after early morning lows around the freezing mark.

Robust moisture advection will evolve from W to E into the
afternoon, with a corresponding increase in broad-scale forcing as
well. The tightening pressure gradient will allow for breezy
conditions to develop within the WAA, which would be enhanced into
the afternoon with the warming of the near-sfc air and onset of
better mixing. Ensemble probs of gusts of at least 35 MPH are
highest near/north of I-70 and across west-central OH, in
particular, Friday afternoon. As is often the case in the WAA setup,
the gustiness will be directly correlated to how warm we can get
prior to the arrival of the rain into mid afternoon and beyond.
There will likely be a several hour period of gusts near 35 MPH
(especially near/N of I-70) before the rain arrives and winds
subside a bit with the better saturation/cooler BL into the evening.

However, there is a strong signal for very steep lapse rates in the
CAA regime following the FROPA late Thursday night into Friday
morning, which undoubtedly will bring additional gustiness (to
around 35-40 MPH) back into the area during the predawn hours
Friday. This gustiness will be maintained at least somewhat into the
daytime with the steep LL lapse rates and good mixing conditions,
with gusts to around 35-40 MPH expected near/north of the Ohio River
corridor into early Friday afternoon.

The other item of interest Thursday night into Friday morning will
be the strong CAA with the relatively tight temp gradient on either
side of the front. This quick drop in temps may allow for the rain
to briefly mix with, and change to, snow before becoming more
isolated late Thursday night. Temps will drop from the lower 50s
Thursday evening to the lower 40s by midnight to the mid/upper 20s
by daybreak Friday. This rapid drop in temps poses a concern
regarding a potential rapid freeze-up, even with the breezy
conditions helping dry pavement/roads. Even still, there will likely
be some precip ongoing during this quick temp drop, so certainly
some slick spots will be possible during the AM commute area-wide.

Scattered shower activity/flurries will likely persist into the day
Friday with the steep lapse rates and sufficient moisture/lift
overlap within the DGZ. Activity may continue into early afternoon
before gradually tapering off from W to E as the best
forcing/moisture pull off to the E. Even still, suppose a few
flurries will be possible through the daytime, particularly near/N
of I-70 where the best moisture will reside downstream of the lakes.

Quieter conditions will then evolve for the remainder of the long
term period as sfc high pressure settles in by Saturday with quasi-
zonal flow aloft becoming established into the weekend. A weak cold
front will bring slightly cooler air into the area by Sunday, but
otherwise near normal to above normal temperatures are expected into
early next week with dry conditions prevailing during this time.

&&

.AVIATION /00Z WEDNESDAY THROUGH SUNDAY/...
A southwesterly jet will move over the region shortly after 00Z
tonight, introducing low level wind shear to all TAF sites during the
overnight hours, around 40 to 50 knots. Wind shear will taper off
shortly after sunrise on Wednesday.

Closer to the surface, things get a bit trickier. Guidance still
wants to hold onto breezy conditions during the overnight, especially
for KDAY and KILN, with gusts to 20 knots possible out of the
southwest. However, am not completely sold on this since forecast
soundings indicate an inversion setting up... which would inhibit
stronger gusts. For now, have gone pessimistic and included the gusts
in the TAFs out of an abundance of caution (especially with the LLJ
cranking right off the surface). Any stronger surface winds will
subside after sunrise, remaining out of the southwest around 10 knots
on Wednesday, before swinging around to the southeast Wednesday
evening.

Similarly tricky forecast with the cloud deck, as guidance is all
over the place on whether this MVFR deck will scatter out and how
quick the blowoff from the next system arrives on Wednesday. For now,
have all sites going VFR by the early morning hours on Wednesday with
high and mid level clouds moving in throughout the day, becoming MVFR
by evening.

OUTLOOK...Wind shear again possible Wednesday night into Thursday.
MVFR to IFR conditions possible Thursday into Friday.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.

&&

$$

SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...
AVIATION...CA