680
FXUS61 KILN 061720
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
120 PM EDT Mon May 6 2024

.SYNOPSIS...
A weak disturbance moving through a warm, humid airmass will
offer showers and a few thunderstorms during the day today. For
Tuesday and Wednesday, multiple systems lifting northeast from
the southern Plains into the Ohio Valley will provide additional
showers and storms. A cold front will bring cooler and drier
conditions Friday into the weekend.

&&

.NEAR TERM /UNTIL 6 PM THIS EVENING/...
A well-defined MCV moving NE through WC KY this morning is
providing a focus for arcing bands of SHRA, with ISO TSRA, about
its center. This MCV, notable on both regional satellite and
radar imagery, will migrate to near KCVG around 00z. The best
potential for redevelopment of convection this
afternoon/evening is likely to occur on the ern/srn flanks of
this feature, mainly in far SE IN, N KY, and far srn OH by late
in the day.

Due to the LL flow fields around the MCV (and the relatively
shallow nature of the convection), storm motion/evolution is
likely to become somewhat erratic late afternoon, especially
very close to the MCV itself. Steering- layer flow should be
fairly weak, which when combined with PWATs of 1.2 to 1.4 inches
and some narrow/weak instby, will once again lend itself to at
least /some/ isolated heavy rain/flooding threat. The focus for
this potential should be in the aforementioned areas,
potentially as far N as a line from Ripley Co IN to Pike Co OH,
with the primary area of concern just south of this line. While
most areas will receive less than an inch (with very
little/none near/N of I-70), some isolated 1-2 inches will be
possible in N KY/far srn OH in the most persistent/slowest-
moving activity. Confidence is not quite high enough to hoist a
Flash Flood Watch at this juncture, but will maintain mention in
the HWO.

With quite a bit of cloud cover and SHRA/TSRA activity about the
region today, forecast highs will generally be in the lower/mid
70s, with sfc DPs nudging back into the mid 60s for most spots.
SHRA/TSRA activity should become more ISO in coverage toward
the evening/beyond, but may not shut off completely tonight as
the weakly-convergent axis continues to crawl to the N.

&&

.SHORT TERM /6 PM THIS EVENING THROUGH 6 PM TUESDAY/...
After an overall lull in the precipitation tonight, another
shortwave will lift into the Ohio Valley Tuesday. With a 50-70
knot H5 speed max accompanying the disturbance, organized
convection and a severe thunderstorm threat remains possible...
particularly during peak heating hours. Highs will lift into the
mid to upper 70s.

&&

.LONG TERM /TUESDAY NIGHT THROUGH MONDAY/...
Thunderstorm activity will linger into Tuesday evening, but we
should see a decreasing trend in coverage and intensity through the
night as we lose some of the instability and the frontal boundary
moves through.

Another mid level short wave will lift northeast across the Ohio
Valley Wednesday into Wednesday night within a sharpening upper
level trough. As it does, a strengthening surface low will move out
of the mid Mississippi Valley Wednesday afternoon and across the
Upper Ohio Valley Wednesday night into Thursday morning. Ahead of
the low, strengthening low and mid level flow will lead to good
moisture advection up into our region late Wednesday into Wednesday
night. As we destabilize through Wednesday afternoon/evening,
showers and thunderstorms will become more widespread into our
southwestern areas late Wednesday afternoon and overspread the rest
of the area heading into Wednesday night. With good low level and
deep layer shear developing, damaging winds, large hail and a few
tornadoes will all be possible. In addition, PWs will climb into
the 1.5 to 2 inch range Wednesday night, so heavy rainfall and some
flooding concerns will also be possible.

Shower and thunderstorm activity will taper off later Wednesday
night into Thursday morning as a cold front moves east across the
area. Cooler air will begin to advect into the region behind the
front on Thursday with afternoon highs ranging from the low 70s
northwest to the upper 70s southeast. The upper level trough will
deepen over the Great Lakes and Ohio Valley region through the end
of the week and into the weekend. This will be accompanied by a
cooler airmass along with some chances for diurnally enhanced showers
and a few thunderstorms. Daytime highs will be mostly in the 60s
Friday through Sunday.

&&

.AVIATION /18Z MONDAY THROUGH FRIDAY/...
Bands of ISO/SCT SHRA, with some embedded TSRA, continue to
pinwheel around an MCV drifting to the NE through far nrn KY.
The best coverage of activity should focus just S/E of this
feature, meaning that KCVG/KLUK will likely see a bit more
coverage than will sites further to the NE. So have a TEMPO for
KCVG/KLUK through the afternoon, with just VC elsewhere.
Activity should decrease in coverage by/past 00z, leaving the
area mainly dry for the overnight.

There continue to be some patchy MVFR (and even IFR) CIGs
lingering about central OH early this afternoon, but most CIGs
have returned to VFR. However, CIGs will once again go back
MVFR, and eventually IFR, by/past 06z, with some LIFR CIGs not
out of the realm of possibility. Some MVFR VSBYs may also
accompany the saturating LL environment tonight into Tuesday
morning. CIGs will go from IFR/LIFR back to MVFR by 15z, and
eventually VFR toward/beyond 18z Tuesday.

Light easterly flow around 5-7kts will go light/VRB/calm tonight
before going more southerly and increasing to around 10-15kts
past 15z Tuesday. A band of SHRA/TSRA should approach from the W
toward 18z Tuesday, likely impacting KCVG/KLUK/KDAY late
morning/early afternoon.

OUTLOOK...Thunderstorms will be possible Tuesday afternoon and
evening and then again late Wednesday into Wednesday night.
MVFR/IFR CIGs are possible Wednesday night into early Thursday
and again on Friday.

&&

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

&&

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