-- Discussion containing changed information from previous version are highlighted. --
429
FXUS61 KILN 010149
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
949 PM EDT Tue Apr 30 2024

.SYNOPSIS...
Tranquil weather conditions are expected through midweek before
rain and storm chances return Friday and continue periodically
into early next week. Above normal temperatures are expected for
the foreseeable future, with very little sign of a notable push
of cooler and drier air through at least early next week.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
-- Changed Discussion --
A nebulous pressure pattern is in place, with generally higher
pressures over the southeastern states, but very weak flow
extending as far north as the Ohio Valley. As clouds have
dissipated, this will set up some decent radiational cooling
conditions tonight, and temperatures are expected to drop well
into the 50s. Some upper 40s may be possible in outlying areas
in central Ohio.

Fog potential looks unchanged from the previous forecast, with
areas of fog most likely in the far southeastern ILN CWA,
including places like Lewis County KY and Scioto County OH.
Still not seeing a strong signal for widespread dense fog, so
the current forecast will essentially be maintained.

Previous discussion >
A small band of SHRA continues to push E through the lower
Scioto Valley and NE KY early this afternoon, with clearing
evolving for many locales near/W of I-71. Suppose that a very
spotty/ISO TSRA cannot be ruled out in the SE quarter or so of
the ILN FA mid afternoon, but expect that most spots will trend
drier by early evening, with increasingly sunny conditions by
late day.

FEW/SCT Cu have developed in the immediate wake of the pcpn as
some LL moisture gradually mixes out into the afternoon.
Nevertheless, skies will trend much clearer by late afternoon
from W to E as that LL moisture mixes out, with a corresponding
late-day jump in temps expected as highs top out in the mid 70s
near/W of I-71. Could even see some upper 70s in parts of SE
IN/N KY, with cooler temps further to the E in NE KY and the
lower Scioto Valley where cloud cover will hang on a bit longer
into late afternoon.

Quiet conditions are on tap for tonight as weak sfc high
pressure briefly builds into the region overnight before
drifting E by Wed AM. The only real item of note for the
overnight will be the potential for some fog development,
especially in NE KY and south-central OH in locations that won`t
have much time to "dry out" before sunset. Additional fog should
develop near/in area river valleys, especially along the OH Rvr
as the LL flow goes calm tonight amidst clear skies and some
residual LL/near-ground moisture.

Lows tonight dip into the lower 50s in central/south-central OH
and NE KY to the mid 50s W of I-75.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM THURSDAY/...
Any patchy to areas of fog should burn off early Wed AM,
especially as LL flow increases and some cloud cover moves in
through mid-morning. This cloud cover will be associated with a
weakening/dying MCS that should fall apart completely before it
approaches from the W around daybreak.

A weak front will sag SE into the local area during the
afternoon/early evening, but forcing and lift along the boundary
should be rather meager. Suppose that a brief/spotty SHRA or
TSRA cannot be completely ruled out mid afternoon into early
evening along the front (especially near the I-71 corridor), but
kept the fcst dry for now given expected lack of coverage
(should anything develop at all) due to persistence of a cap.

Regardless of whether we are able to get a spotty SHRA/TSRA to
sprout Wed afternoon/early evening, it will certainly /feel/
like early summer as highs reach into the upper 70s and lower
80s with sfc DPs in the mid 60s ahead of the front. Behind the
front (EC IN and WC OH), sfc DPs will fall into the upper
40s/lower 50s late in the day.

Lows Wednesday night dip into the mid 50s (WC OH and central
OH) to lower 60s (near/S of OH Rvr) amidst dry conditions.

&&

.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
Thursday and overnight will be the highest max/min of the forecast
period, with the overnight low being roughly 15 degrees above
climatological normals. Afterward, there does not appear to be much
day to day variability as both low and high temperatures are roughly
10 degrees above climo.

H5 ridge axis moves east Thursday night and s/w energy on the back
side is brought in on the southwest flow aloft early Friday. This
coincides with a cold front associated with a northward moving
surface low over northern MN. A slight chance of showers in the
west/northwest towards daybreak will become a more reasonable
expectation as morning wears on, along with some stronger convection
supporting thunder. This is especially noted during the afternoon.
Evening should see the bulk of the rain moving east and through the
CWA, with a decrease overnight. Looking at NBM, timing of the back
edge of rainfall seems to be too far out, lingering into Saturday.
All indications show the s/w energy in eastern CWA at daybreak and
well east of us by 18Z. Shaved pops a bit towards this direction but
expect the change to be fairly negligible.

L/w ridging on Sunday night extending nw-se will be undercut by s/w
energy in the southern Ohio Valley, necessitating some type of rain
mention through the weekend. Expectations on my part during this
time is for a much lesser occurrence/duration that can`t be
expressed this far out in the forecast. However Sunday works out,
Monday does stand to have a higher likelihood of the region
experiencing another shot of rain. This chance has evolved in the
NBM as an even higher chance of showers and thunder through Monday
night and into Tuesday. I`m not of a particular understanding as to
what evolution and features this model is keying off of, and expect
the weight of ensemble members this far out is muddying the waters
for this time frame.

&&

.AVIATION /02Z WEDNESDAY THROUGH SUNDAY/...
VFR conditions are expected through the TAF period, with the
exception of some fog tonight. Showers have moved out of the
area, with just a few cumulus clouds over the area right now.
These clouds should dissipate over the next few hours.

With generally light winds tonight, valley fog is expected to
develop, so IFR visibilities are in the forecast for KLUK. The
forecast will be kept VFR for now at the other sites, though
there is a low-end chance for some MVFR at KILN and KLCK as
well.

Tomorrow, dry conditions are expected, with some mid clouds and
cumulus clouds expected at times. Increasing southerly winds
will bring a few gusts to around 20 knots, particularly for
KDAY/KCMH/KLCK/KILN.

OUTLOOK...Thunderstorms are possible at times on Friday,
Saturday, and Sunday. MVFR ceilings are possible Friday into
Saturday.

&&

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

&&

$$
SYNOPSIS...KC
NEAR TERM...KC/Hatzos
SHORT TERM...KC
LONG TERM...Franks
AVIATION...Hatzos