-- Discussion containing changed information from previous version are highlighted. --
095
FXUS61 KILN 220746
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
346 AM EDT Wed May 22 2024

.SYNOPSIS...
-- Changed Discussion --
Seasonably warm temperatures continue through the entire week
into the upcoming weekend. Periods of showers and storms will
occur at times through the upcoming weekend and early next
week, with an unsettled pattern expected through at least
Monday.
-- End Changed Discussion --

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
-- Changed Discussion --
Several loosely-organized clusters of SHRA/TSRA continue to
work to the ENE across IL/IN early this morning, with the
expectation for this activity to move into the ILN FA shortly
before daybreak. Anticipate that the activity will be in a
weakening phase, especially with eastward extent, as it will be
outrunning its source forcing/lift and encounter an increasingly
unfavorable environment with eastward extent. This being said,
often times the storms are able to survive and maintain a bit
longer than perhaps some guidance suggests. So the inclination
is that at least /some/ convection will be maintained into the
ILN FA through the morning hours, likely providing a few rumbles
and perhaps some brief gusty winds as the storms move through.
At the very least, some patches of light rain and extensive
cloud cover will overspread the local area this morning,
continuing to wane with eastward extent into late morning.

Subsidence and a stable environment should evolve in the
immediate wake of the AM ISO/SCT SHRA/TSRA, delaying the best
destabilization efforts toward early afternoon. While robust
destabilization should eventually evolve/advect in (especially
near/E of I-71), there remain some questions regarding coverage
of redevelopment during the afternoon itself as the LL
southwesterly flow is largely parallel to the approaching
front/boundary, with very little in the way of pronounced LL
convergence or forcing or lift. This is not to say at all that
there won`t be a few storms that redevelop amidst the
increasingly-unstable environment during mid/late afternoon
(especially in central OH to south-central OH and NE KY where
the best instby will be located by 18z-21z), but with a lack of
focused forcing or lift, we may end up in a scenario where most
spots stay dry this afternoon into early evening. This may be
especially the case as the latest guidance suggests the front
getting slightly further E than previously indicated, with some
mixing down of dewpoints in EC IN and WC OH by late in the day
in the post-frontal environment, essentially shunting all
potential for storms a bit further S.

Will continue mention of a few strong to severe storms in the
HWO, but coverage of said storms may be much more limited than
originally anticipated. Needless to say, the forecast has
trended to a less concerning setup for today, despite the
continued low-end potential for a few strong to severe storms
with gusty/damaging winds. Highs today reach into the lower/mid
80s amidst filtered afternoon sunshine.
-- End Changed Discussion --

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM THURSDAY/...
-- Changed Discussion --
For late this evening into tonight, some lingering SHRA/TSRA
will persist through the nighttime, mainly near/S of the OH
Rvr, but the prospect of a more widespread strong to severe
storm potential for tonight is quite low.

Coverage of activity should increase gradually past midnight
into the predawn hours, particularly near/S of the OH Rvr, with
one or more clusters of storms possible in these areas overnight
into Thursday morning. So a few rumbles are expected from time-
to-time through the night tonight across srn parts of the area.

By the afternoon, the stalled front will attempt to nudge back
to the N, perhaps getting somewhere in the vicinity of the I-70
corridor. This will occur as a S/W ejects E through KY, with
better instby advecting back into the srn half or so of the ILN
FA. The forcing for convection Thursday appears to be
(ironically) better/greater than will be the case today,
particularly for srn parts of the local area and N KY where
SHRA/TSRA activity by early to mid afternoon should be fairly
widespread. Suppose that an isolated strong to severe storm
cannot be ruled out Thursday morning into the afternoon,
especially if ample destabilization can take place with an
influx of better LL moisture to the N into early afternoon.
Gusty winds again would be the primary threat, along with very
heavy downpours and brief ponding of water on roads in the most
persistent storms (as PWATs will be >=125% seasonal norms).
Expect the best coverage during the daytime Thursday to be near,
and especially S of, a line from Franklin Co IN to Fairfield Co
OH.

More expansive cloud cover and pcpn should keep high temps a
bit cooler (mid/upper 70s) in N/NE KY and the lower Scioto
Valley compared to other locales further to the NW in WC OH and
EC IN (lower 80s) where there will be some sunshine.
-- End Changed Discussion --

&&

.LONG TERM /THURSDAY NIGHT THROUGH TUESDAY/...
-- Changed Discussion --
The extended period will begin in a zonal flow pattern as periodic
pieces of shortwave energy push east across the Ohio and Tennessee
Valleys. The first of these should bring an increase in cloud cover
and precipitation on Friday, mainly across our southern reaches of
the CWA.

A drying period looks to arrive on Saturday before a stronger
disturbance approaches Sunday. At this time, guidance shows a rather
deep surface low tracking across Wisconsin and Lake Michigan on
Sunday/Sunday night which would increase the potential for strong to
severe storms (increased vertical wind profile, better forcing).

An upper trough moves into the Great Lakes and Ohio Valley late
Monday into Tuesday, finally bringing a return to near normal
temperatures after an extended warm spell.
-- End Changed Discussion --

&&

.AVIATION /07Z WEDNESDAY THROUGH SUNDAY/...
A few VFR Cu are lingering about the area amidst
increasing/thickening mid/high level clouds, which will
continue to overspread the area through daybreak. An
elongated/broken cluster of convection will move in from the W
around/after sunset, with latest guidance suggesting it will
hold together long enough to bring some SHRA, as well as ISO
TSRA potential, to KCVG/KDAY/KLUK and even KILN between about
10z-14z. Did not yet have confidence to add TS to the fcst, but
did add tempo SHRA at each of these sites to account for the
slightly better coverage of activity as it moves in through
the morning hours.

The broken/loosely-organized convection will continue to fall
apart beyond 15z, with some ISO SHRA/TSRA expected to develop in
its initial wake between 15z-18z or so. Activity through the
daytime, especially for the afternoon, will be very disorganized
and somewhat spotty, with some indications for better coverage
of development past 22z near KCVG/KLUK, but confidence is rather
low in whether the sites will have much SHRA/TSRA activity
beyond the decaying AM convection. A chance of SHRA/TSRA may
linger toward/beyond the end of the period, especially for srn
sites of KCVG/KLUK.

Some MVFR CIGs cannot be ruled out between about 14z-18z in the
immediate wake of the weakening AM activity, but conditions
(outside of SHRA/TSRA) should be mainly VFR. Southerly winds
around 5-10kts will increase to 10-15kts, and gust to around
20-25kts, out of the SW past 14z or so. The gustiness should
subside just a bit toward/beyond 21z, with sfc flow going more
westerly at around 5kts by the end of the period.

OUTLOOK...Thunderstorms possible Wednesday night and Thursday
and then again on Friday into Saturday as well as Sunday. MVFR
ceilings possible Wednesday night into Thursday.

&&

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

&&

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