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009
FXUS61 KILN 170207
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
1007 PM EDT Sun Jun 16 2024

.SYNOPSIS...
Building high pressure aloft will combine with surface pressure
increases and a southerly flow in the Ohio Valley to bring an
atypically extended period of high temperatures for the coming
week. Highs in the mid to upper 90s will be compounded by low
temperatures from 70-75, worsening any heat related issues a
little more each successive day. Some weak disturbances along
with daytime heating may trigger thunderstorm activity on
Monday and possibly Tuesday.

&&

.NEAR TERM /UNTIL 6 AM THIS MORNING/...
-- Changed Discussion --
Tranquil conditions continue to reside across the local area,
but a surge of LL moisture is advancing to the NNE and will
overspread the ILN FA through the latter half of the overnight
period. This means that dewpoints in the upper 50s/lower 60s
will be replaced by dewpoints in the upper 60s/lower 70s for
many locales by sunrise. This surge of LL moisture should
inhibit temps from dipping too much, especially late in the
night where temps should largely plateau across the area...
generally staying in the upper 60s/lower 70s by daybreak.
-- End Changed Discussion --

&&

.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM TUESDAY/...
More than a handful of convective allowing models are showing
scattered storms over the CWA in the afternoon and early
evening, then rapidly calming down with the setting sun. If
storms develop in this weakly sheared atmosphere, they should be
short-lived but have a higher than average for strong downburst
winds. Outflow boundaries would also have a decent potential for
initiating more activity.

High temperatures should reach into the low to mid 90s.
Convective temperatures in 88-90 range will also help to spur
development of afternoon storms. Any cooling from outflows
and/or thicker cloud cover associated with the storms is
probably the best limitations to where these storms remain
scattered.

Dew points rising into the upper 60s to lower 70s will create,
maximum heat indices will be around 100. This is the bare-
minimum heat advisory criteria. Continue to keep the excessive
heat watch in favor of new model guidance overnight or
potentially early Monday if forecast later tonight is
inconclusive. Expect watch to resolve in an advisory or no
headline for Monday, but heat messaging is solidly in place.

Overnight lows will range from the mid 70s in west central OH to
the lower 70s south of the I-70 corridor into northern KY.

&&

.LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/...
With an anomalously strong high pressure centered to the east
through the period, hot temperatures are the main story. Latest
model blend shows highs in the low and mid 90s Tuesday and
Wednesday, rising to the mid and upper 90s Thursday through
Saturday, then back to the low and mid 90s Sunday. Apparent
temps are a few degrees higher, peaking around 100 in isolated
spots. Nighttime readings in the 70s will offer little relief.
Though temps will be borderline for heat headline criteria, the
duration of the heat will be a problem. Excessive heat watch
remains in effect into Friday evening, while upgrading to heat
advisories or warnings may be necessary over the coming days.

Dry weather is expected for the most part. Thunderstorms will
be possible Tuesday afternoon as a shot of moisture and PVA
circulates around the high. The threat for showers and storms
returns next Sunday when the high is forecast to break down
ahead of a trough and cold front. That will leave a dry period
from Wednesday through Saturday when the heat may be unimpeded
by precipitation and widespread clouds.

&&

.AVIATION /02Z MONDAY THROUGH FRIDAY/...
Mainly clear skies remain entrenched across the local area, but
a FEW VFR Cu will begin to work in from the S toward/beyond
06z on the leading edge of some more robust LL moisture, with
additional SCT/BKN diurnally-driven VFR Cu development by/after
15z. Some ISO/SCT convection is expected to develop near/after
18z, initially around KCVG/KLUK before activity develops
elsewhere and expands/spreads to the NE through the afternoon.
Activity should be very disorganized/cellular in nature, so
challenges involving pinpointing timing and location at this
juncture yield enough uncertainty that decided to keep the TAFs
dry for now, even with the expectation for ISO/SCT storms for
the afternoon. A VCTS or TEMPO group will likely eventually be
warranted as details become a bit more clear.

Light southerly flow through the morning hours will become more
out of the SW by/after 15z at around 7-9kts or so. Some highly-
localized gusty winds are expected with convection that
develops during the afternoon, but such occurrences will be
handled with amendments as needed. Some river valley BR/FG will
be possible at KLUK as a surge of LL moisture arrives past 06z,
leading to the potential for some MVFR VSBYs at the site in the
several hours around daybreak.

OUTLOOK...No significant weather expected.

&&

.ILN WATCHES/WARNINGS/ADVISORIES...
OH...Excessive Heat Watch from Monday afternoon through Friday
     evening for OHZ026-034-035-042>046-051>056-060>065-
     070>074-077>082-088.
KY...None.
IN...Excessive Heat Watch from Monday afternoon through Friday
     evening for INZ050-058-059-066-073-074.

&&

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