154
FXUS61 KILN 161801
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
201 PM EDT Wed Apr 16 2025

.SYNOPSIS...
Dry conditions continue mid-week before a low end chance for precipitation
returns Thursday afternoon into Friday early hours. Additionally, a
notable warmup will arrive for the end of the working week.
Precipitation returns to the forecast for the weekend, with multiple
rounds of rain expected.

&&

.NEAR TERM /THROUGH TONIGHT/...
Upper level ridging and 1025 surface high pressure continue to be the
primary influencer for our weather. Consequentially, mass subsidence
promotes mostly clear skies overnight and strong radiational
cooling. Overnight low temperatures fall into the low to mid 30s in
central Ohio/ Kentucky, upper 30s closer to the Tri-State. Very light
to calm winds will promote frost formation in areas where
temperatures fall low enough, so have a Frost Advisory issued for
much of the area. Outside of frost, there is also a signal for valley
fog, particularly in areas where a moisture source is present. Due
to the dry airmass in place, do not think that other areas will have
fog issues.

&&

.SHORT TERM /THURSDAY/...
Thursday acts as a transition day as the upper level ridge and
surface high begin to get shunted east thanks to troughing in western
CONUS and a broad area of surface low pressure deepening on the
eastern side of the Rockies.

Due to the above, southerly flow returns to the Ohio Valley Thursday
and there is a chance for showers during the afternoon hours as a
warm front lifts north through our area. This feature helps usher in
warmer temperatures and an influx of moisture. High temperatures on
Thursday climb into the 60s.

Any lingering rain showers move off to the northeast during the
evening hours and we dry out, though we will be squarely warm
sectored in the approaching system. As such, overnight lows will be
in the mid 50s and dew points continue to rise during the night.

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
Positive midlevel height anomalies will evolve across the ern CONUS
for the start of the long term period, with /very/ warm air
filtering into the OH Vly ahead, and on the ern periphery, of a
northeast-advancing an initial low pressure system fcst to move
through the mid MS Rvr Vly into the nrn Great Lakes Friday into
Friday night. This will place the ILN FA squarely in the heart of
the open warm sector amidst a tightening pressure gradient. A well-
mixed BL will evolve by the afternoon, supporting very warm and
breezy conditions locally with mostly sunny skies. A few patches of
mid/high clouds may be the lone hindrance to temps soaring to around
80 degrees by late afternoon, but widespread upper 70s are expected
by late in the day within stiff SW sfc flow on the order of 20-30
MPH.

Dry conditions should prevail locally through the entirety of the
daytime Friday before showers/storms gradually drift to the ESE into
the area toward late evening. The initiation/genesis region of this
activity will be well to the WNW of the ILN FA in an environment
characterized by a much-more supportive thermodynamic and kinematic
environment. In fact, the latest trends within the ensemble suites
suggest a further delayed arrival of the activity with the low center
being positioned slightly further /away/ from the local area,
lending itself to considerable uncertainty regarding the severity, or
at the very least the expanse of severe storms, into the local area
Friday night into very early Saturday. There is very little doubt
that an axis of scattered to numerous showers/storms will eventually
pivot its way into SE/EC IN and WC OH near/after midnight, but with
increasingly-meager mid/low level lapse rates into the nighttime
period, the prospect of a corridor of steady shower/storm activity
moving into areas near/N of I-71 seems much more plausible than does
a pronounced severe weather episode within this same time/space.

Eventually, the pivoting axis of shower/storm activity will begin to
slow/stall/weaken before crawling back to the N into the daytime
Saturday. The specifics of when/where this occurs remains to be
seen, but the latest ensemble data supports a slower/further N
solution, which would mean that locales across NE KY and the lower
Scioto Valley into south-central OH may end up staying mostly, if
not completely, dry into Saturday morning.

Into/beyond Saturday afternoon, the data becomes a bit more
dispersive, with an increasingly-large envelope of solutions as we
progress into Sunday/Monday. However, there is a signal for the
parent system to finally move through the area during the day
Monday, promoting increased shower/storm chances in a widespread
nature for the start of the workweek, followed by a drier spell into
midweek of next week. The coverage of shower/storm activity late
Saturday into Sunday remains a bit uncertain, owing to differences
in handling of the track of the parent low pressure system out of
the south-central plains and into the mid MS/OH/TN Vlys into
Sunday/Monday. A quicker/southern ejection of this low to the NE
would preclude the front from moving back too far to the N, keeping
better shower/storm chances entrenched across the area Saturday
night into Sunday. However, a slower/further N track of this low
pressure system (favored) would likely mean the front is able to
pivot far enough N as to allow for a drier stretch to briefly evolve
late Saturday through Sunday, particularly near/S of I-71.

The unsettled pattern should quiet a bit as we progress into the
middle of next week, with slightly above normal temps favored toward
the end of the long term period. As a whole, temps through the long
term period will be above normal, with at least several days with
highs in the 70s and lows in the 50s/60s.

&&

.AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
High pressure in control over the region and VFR conditions continue.

Some scattered cu moving through the region this afternoon with
west/northwesterly flow around 10 knots with periodic gusts to 20
knots through the afternoon.

Winds sharply decrease after sunset and go calm/ light and variable.
Given mostly clear skies, there is some concern for fog in areas that
have a moisture source (KLUK comes to mind). Went ahead and included
VSBY reductions briefly at KLUK, however KILN and KDAY may also
experience early morning brief reductions. Lacked confidence at these
two sites due to very dry airmass in place, so moisture would need to
come from surface foliage.

Southerly flow around 10 knots returns on Thursday with high clouds
moving in from southwest to northeast. Chance for afternoon showers,
though confidence on timing is low at the moment.


OUTLOOK...MVFR/IFR conditions possible along with a chance of
thunderstorms Friday night into Saturday.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...Frost Advisory from midnight tonight to 9 AM EDT Thursday for
     OHZ026-034-035-042>046-051>056-060>065-070>074-077>082-088.
KY...Frost Advisory from midnight tonight to 9 AM EDT Thursday for
     KYZ097>100.
IN...Frost Advisory from midnight tonight to 9 AM EDT Thursday for
     INZ050-058-059-066.

&&

$$

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