402
FXUS61 KILN 030811
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
411 AM EDT Fri May 3 2024

.SYNOPSIS...
A weak cold front will move east across the area later today
and into tonight. This will bring showers and a chance for
thunderstorms today into Saturday, along with some cooler
temperatures.

&&

.NEAR TERM /UNTIL 7 PM THIS EVENING/...
Embedded mid level energy in southwest flow aloft will lift
northeast across the Ohio Valley region through this afternoon.
This will be accompanied by a weak cold front that will push
into our area from the west later today. Moist southwest flow
ahead of this will allow for showers to overspread mainly our
western areas through mid morning and then the remainder of our
area heading into this afternoon. Instability will remain
fairly marginal so will just allow for a chance of some
embedded thunderstorms today. With some cooler air moving in
from the west, highs today will range from the mid 70s west to
the lower 80s east.

&&

.SHORT TERM /7 PM THIS EVENING THROUGH 6 PM SATURDAY/...
The mid level energy will push off to the east through tonight
as the weak cold front gradually weakens as it moves across our
eastern areas. As a result, expect an overall decreasing trend
in pcpn from the west tonight with overnight lows in the upper
50s to lower 60s.

Southwest flow will persist aloft through the day on Saturday
with some weak mid level energy again lifting northeast across
the region. Afternoon highs will be in the mid to upper 70s
with sbcapes climbing up to around 1000 J/KG or so through the
afternoon. With forcing aloft fairly weak, will limit pops
to mainly chance category across much of the area for Saturday.
The exception may be across our east, closer to the washing out
front, where will include some likely pops across at least our
far east during the afternoon.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
While the forecast may seem a bit muddied with a potential of
showers and thunderstorms through the period, there is good
reasoning to have them there.

First, overnight lows are only 5-10 degrees below normal. Normal
high temperatures. A clear signal where temperatures across the
region drop below 60 overnight doesn`t seem to come about until
Friday night (beyond this forecast). Thursday night looks to be
within a few degrees of 60 across the CWA, but until then, 60-65 is
expected. The warmest nights will be Tuesday and Wednesday where
some locations to the southeast might only drop into the upper 60s.

This prolonged period of overnight warmth leads to/stems from an
abundance of moisture in the area. Couple this moisture with high
temperatures generally running from the mid 70s to around 80 and
forcing mechanisms at the surface or aloft at one time or another,
and you just can`t rule out shower and thunderstorm activity. More
like summer, only without the blisteringly higher temperatures one
might expect.

During the period, Tuesday will see everyone within a few degrees of
80 but Wednesday will be the warmest with lower 80s expected, and
some mid 80s possible in the southern CWA. Both high and low
temperatures from the Euro ensembles show a fairly tight standard
deviation of 2-3 through the entire forecast, meaning a higher
confidence in narrowing the expected range in both high and low
temps.

Second, lifting mechanisms of one sort or another remain a larger
than average threat to be over the Ohio Valley and CWA for this
period. Saturday night will start with lingering storms that should
be decaying after initiation from daytime heating. A cold front is
pushing in overnight and while weakening, is still moving into a
relatively moist environment and could propagate any lingering
storms through the night. This front stretches and weakens on
Sunday, but maintains a moisture boundary due to a strong high
pressure center to the north. This could lead to showers over the
southern CWA during the day and more overnight as the remnant
boundary becomes more pronounced from w-e. Monday/Monday night keeps
the boundary stretched through the CWA. It exits north-northeast on
Tuesday and NBM pops given are much too high with likely in the
west. A simple chance of showers/storms would be the better middle
ground forecast.

Now on Wednesday, warm sector showers/storms on southwest flow are
more likely and could continue overnight. A surface low/front is
progged on Thursday with the mean sw flow aloft not showing much
change. Friday`s potential of storms is focused on the potential of
a surface low developing near/west of the CWA ahead of a l/w H5
trough, with the low dropping a front through the region.

The cumulative pattern suggests potential rainfall/flooding issues
either with individual MCS episodes or from repeated rounds of
convection. This is as the upper ridge slowly flattens and low-mid
level flow lines up wsw by mid week. Starting Friday, an effective
frontal passage should begin to settle south of the area with
cooler/drier conditions possible for the weekend.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
Mid level energy will lift northeast across the region today
into tonight. This will lead to periods of rain showers and
perhaps a few embedded thunderstorms. While most of the day
will not be a wash out, skittered showers will be possible at
times through much of the TAF period. Will generally handle
this with a VCSH. CAMs are suggesting the best chance for more
widespread pcpn will be during the mid afternoon hours and will
try to hit a period around that time with a prevailing
-shra. Cigs will gradually trend downward today with some MVFR
 cigs possible this afternoon.

OUTLOOK...Thunderstorms possible at times Saturday through
Tuesday. MVFR ceilings are likely Friday night into Saturday,
with IFR ceilings and MVFR VSBYs possible Friday night into
Saturday morning. MVFR conditions are possible again Sunday
morning.

&&

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

&&

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