091
FXUS61 KILN 201035
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
635 AM EDT Mon May 20 2024

.SYNOPSIS...
Much above normal temperatures and mainly dry conditions are
expected today, with a chance of showers and storms returning
as early as Tuesday. The next widespread chance for showers and
storms is likely Wednesday into Thursday with the approach and
passage of a cold front. Slightly cooler conditions are in
store for the end of workweek, although there may be additional
chances for showers and storms by Friday into the upcoming
weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
Earlier convection in far NW stretches of the ILN FA has long
dissipated, with the convective debris clouds also now thinning
out, per latest satellite imagery. This has yielded mainly clear
skies, with just a FEW/SCT cirrus from time-to-time, especially
near/N of the OH Rvr.

Temps will dip into the lower 60s for most spots by daybreak,
with a few upper 50s still possible in rural/sheltered locales.
Any fog development should be confined to the larger river
valley spots, with abundant sunshine expected to start the day
for most in the local area.

A FEW/SCT diurnally-driven Cu will sprout about once again for
the afternoon, but the potential for a stray SHRA/TSRA is once
again very low. Through the afternoon/early evening, the best
potential for a rogue SHRA/TSRA will be in far nrn parts of the
local area, perhaps near Logan/Hardin/Union Counties in Ohio
between about 18z-23z. In fact, the best chance may once again
evolve in parts of WC OH after sunset into the nighttime period
tonight, but even this potential is still quite low.

The main item of interest for today will again be the
unseasonably warm conditions, with highs reaching into the
upper 80s for many. Suppose that the 90-degree mark will be
within reach for the typical warm spots about the area. While it
is not expected that the standing daily record highs at
Cincinnati/Columbus/Dayton of 92/91/91, respectively, are in
jeopardy, it isn`t out of the realm of possibilities to get very
close to tying a record, especially at Columbus/Dayton.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
While the short term period is not expected to be active, there
will be /some/ activity to keep an eye on from time to time. The
first of this will be associated with a weakening S/W
approaching from the W this evening, moving into the local area
overnight. There may be one or more small clusters of weakening
convection that make their way into the local area (specifically
WC OH) around/after midnight, but confidence on maintenance of
this activity with eastward extent is fairly low. Do think that
some of the same areas that saw some ISO/SCT convection earlier
this evening will be the favored areas once again, especially
late this evening/early overnight from WC into central OH. Have
included a slight chance PoP in these areas to account for this
potential as the radar will most likely not be completely clear
into early tonight.

Otherwise, expect another warm and humid overnight period with
temps dipping into the mid 60s.

Another /very/ warm day is on tap Tuesday, which may end up
being the warmest day of the week. In fact, would expect that
the best chance to hit the 90-degree mark for the first time of
the year will be Tuesday as midlevel ridging will briefly build
in once again (especially across the wrn parts of the area) as
the potent S/W ejects to the NE through the upper Midwest. While
there will be slight chance for a few afternoon/evening
SHRA/TSRA in central OH as remnants of the weak S/W linger, most
areas should stay dry once again. Highs top out in the upper
80s to around 90 degrees amidst a subtle strengthening in the LL
southwesterly flow and a mix of sun and clouds.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SUNDAY/...
There is an uncommonly high degree of uncertainty for the day
3/4 forecast. In general, strong low pressure will be lifting
northeast into the Upper Midwest to start the period Tuesday
night, while a high-amplitude ridge is centered over the United
States Eastern Seaboard. At this time, guidance is struggling
with how much progress the low and its associated cold front
make into the ridge for mid-week.

Looking at the European ensemble, quite a few members show little
forcing and only isolated PoPs heading into Wednesday morning, with
most showing some convection developing from midday into the
afternoon well ahead of a lagging cold front. Severe weather
potential is also uncertain... but it appears the best upper level
support for organized thunderstorms remains to our southwest and
west, with maybe some threat spreading into east-central Indiana and
west-central Ohio on Wednesday. Due to this, will keep a mention in
the HWO with low-end confidence at this time.

There will likely be showers and a few storms Wednesday night into
the day on Thursday depending on the progress of the slow-moving
cold front. The ECMWF is most progressive with the system (less PoPs
on Thursday) while the GFS slows things down (more PoPs on
Thursday). Either way, most guidance stalls the front to our south,
setting up additional shower and storm potential Friday, especially
across our southern counties. In the meantime, Thursday and Friday
may have closer to normal temperatures as the mid-level ridge gets
shunted a bit to the south and east of our CWA.

Sensible weather becomes even more uncertain heading into the
weekend. It seems prudent to keep a good chance of precipitation
(per the blend) with a stalled front in the area. In fact, both the
GFS ensemble and the European ensemble maintain a better than 50%
probability of >0.1" QPF through the weekend.

&&

.AVIATION /12Z MONDAY THROUGH FRIDAY/...
After the BR at KLUK dissipates early in the TAF period, VFR Cu
around 5-6kft will sprout about again area-wide for the
afternoon before waning in coverage past sunset. There will be
some increased cloud cover, and perhaps some ISO convection
near/N of I-70 after 18z. Moreover, additional weakening SHRA or
TSRA will approach parts of WC OH toward 06z, but this activity
should stay NW of even KDAY. The weakening convection spilling
into WC OH by/after 06z will bring with it some thickening
mid/high level clouds. There may be some ISO activity that
lingers past 06z in WC OH so it may not be dry /everywhere/, but
lack of coverage inhibited inclusion of even a VC at KDAY at
this time.

Light/VRB/calm winds will go more out of the SSW during the
daytime, staying generally 6-8kts or less through the period.
Light southerly winds at 5kts or less will be maintained during
the overnight.

OUTLOOK...Thunderstorms likely at times Wednesday into Thursday
morning. MVFR/IFR ceilings and visibilities to linger into
Thursday. Additional chances for thunderstorms are possible
Friday.

&&

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

&&

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