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147
FXUS61 KILN 121952
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
352 PM EDT Sun May 12 2024

.SYNOPSIS...
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High pressure will move off to the east tonight and Monday. Low
pressure will move out of the Ozarks and track east across the
Ohio Valley Monday night through Wednesday, resulting in
unsettled conditions across the region.
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&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
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For tonight, a surface high pressure ridge will continue to
move east. A southerly flow pattern can be expected at the
surface between the departing high and a frontal system sagging
southeast into the western Great Lakes. Just some scattered high
clouds are expected. It will be warmer, especially across the
northwest where winds will be the highest. Lows will range from
the upper 40s far east to the upper 50s far northwest.
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&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
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For the first part of Monday, a mid level ridge axis will
traverse east across the Ohio Valley. Once this axis goes by,
there will be an increase in mid and high level clouds, mixed
with some diurnal cumulus clouds. Southerly flow will increase,
becoming locally gusty (20 to 25 mph) in the afternoon. By late
in the day, deeper moisture will increase from the southwest
ahead of the next weather system. This may bring a low chance of
a shower late in the day, mainly west of the I-75 corridor. It
will continue to warm from the previous day with highs ranging
from 75 to 80.

By Monday night, a lead s/wv ejecting ahead of a mid level
trough over the middle Mississippi River Valley will bring
moisture and lift. This feature, coupled with a modest low
level jet, will result in numerous showers as they pivot
southwest to northeast overnight. There will be enough
instability for a few embedded thunderstorms. Clouds and
higher humidity will keep overnight lows warm, mostly in the
60s.
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&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
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On Tuesday morning, an upper low over the middle Mississippi
Valley region will be opening up into a wave, moving very slowly
eastward into the Ohio Valley. Flow into the ILN CWA will
generally be southerly at the surface, switching to
southwesterly through the 850mb-700mb layer. This pattern will
support general ascent over the region, with enough moisture and
destabilization to provide a chance for showers and
thunderstorms. There may be a diurnal minimum at the beginning
of the day, with additional showers and storms developing by
afternoon and evening. Broader forcing in the southern sections
of the forecast area will exist, as well as some more focused
forcing ahead of a cold front moving southward into northern
Indiana and Ohio. By Tuesday night, a surface low associated
with this entire system will be weakening as it tracks east into
the area. Would not be surprised to see some slow storm motions
and localized heavy rain. However, the overall instability and
wind shear projections are not looking especially favorable for
severe weather.

By Wednesday morning, the surface low will be washing out, but
the upper trough will still be lumbering its way to the east.
This will keep a chance of some additional showers in the
forecast -- and possibly a thunderstorm, with some cooler air
moving in aloft providing some steeper lapse rates. Once the
trough axis has departed the area, dry conditions are expected
late Wednesday into Wednesday night.

Ridging and surface high pressure will bring drier conditions
on Thursday. Confidence is low in the pattern for Friday and
Saturday, as there remains model disagreement in how quickly
southerly flow and upstream troughing will return to the area.
There are also differences in just how amplified the pattern
will get heading into next weekend. Friday is looking a little
more likely to have rain in the area, with lower confidence in
timing for the next system or two beyond that.

With the trough still in the area, temperatures on Tuesday and
Wednesday will be in the lower 70s for highs. A warming trend is
expected beyond that, with values reaching the upper 70s to
lower 80s by Sunday.
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&&

.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
North to south surface ridge axis was located across the region
this afternoon. Only a FEW high based cumulus clouds and a FEW
cirrus clouds were noted. Winds will shift to the west/southwest
as the axis passes by. Winds will become southerly in nature by
00Z Monday.

For tonight, surface ridge will continue east. A southerly flow
pattern can be expected at the surface between the departing
high and a frontal system sagging southeast into the western
Great Lakes. Just some SCT cirrus is forecast overnight. There
could be some shallow MVFR mist at KLUK between 08Z and 12Z.

On Monday, a mid level ridge axis over the middle Ohio Valley
will pass off to the east. This will allow an increase in mid
and high clouds to occur from the west during the day. Some
diurnal cumulus will develop around 16Z as southerly winds
increase and become locally gusty between 15 and 20 knots.
Moisture ahead of the next weather system to our southwest may
bring a low chance of showers near KCVG toward 00Z Tuesday.

OUTLOOK...MVFR ceilings and visibilities are likely Monday
night into Wednesday, with a period of IFR ceilings and
visibilities possible. Thunderstorms will also be possible
Monday night into Tuesday night. MVFR ceilings and visibilities
possible Friday.

&&

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

&&

$$
SYNOPSIS...Hickman
NEAR TERM...Hickman
SHORT TERM...Hickman
LONG TERM...Hatzos
AVIATION...Hickman