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000
FXUS61 KILN 260628
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
228 AM EDT Fri Apr 26 2024

.SYNOPSIS...
High pressure over the Great Lakes will move east today, with
dry weather continuing for the Ohio Valley. A warming trend will
begin on Friday, as an upper level ridge moves east of the
region. Precipitation chances will increase starting on Friday
afternoon, with a warm front moving into the area.

&&

.NEAR TERM /THROUGH TONIGHT/...
Surface high pressure is centered over southern Ontario, with
light ENE flow over the middle Ohio Valley. Mostly clear
conditions are expected through the near term.

With a dry air mass and mostly clear skies, tonight will be
somewhat favorable for falling temperatures and frost
development. The one limiting factor is the wind flow, which
will not go completely calm. With that in mind, freezing
temperatures are not generally expected, and temperatures cold
enough for frost will only impact less than half of the
forecast area tonight. A Frost Advisory was coordinated with
surrounding offices and issued for parts of west-central and
central Ohio.

&&

.SHORT TERM /SATURDAY/...
At 12Z Friday, high pressure will have moved east into New
England, and a mid-level ridge axis will be just upstream of the
ILN CWA. As this axis moves east, SSW flow on its back side will
begin an increase of theta-e into the area. While there may not
be a very well-defined surface front, moisture convergence and
theta-e advection at 850mb will be more pronounced, and a band
of showers (with possibly some embedded thunderstorms) will move
into the area late in the afternoon and into the evening.
Precipitation chances appear highest in the northwestern ILN
CWA, where the forcing is a little bit stronger. Behind this
initial wave of precipitation, chances will continue into the
overnight hours, but they will be much more spotty and limited.

Temperatures should warm appreciably before the thicker clouds
and precipitation move in Friday afternoon, with highs reaching
the upper 60s to mid 70s -- with the warmest temperatures in
south-central Ohio and northeast Kentucky. There is some
potential for this area to reach the upper 70s tomorrow.

&&

.LONG TERM /SATURDAY NIGHT THROUGH THURSDAY/...
The first of two mid level shortwaves will be moving off to the
northeast and the band of showers associated with the warm
front from this system will have progressed out of the area.
This leaves us in a warm airmass with strong southerly flow as
ridging moves in aloft. Breezy southerly winds remain in place
and we gust to 30 MPH or so on Saturday.

Since there aren`t any synoptic or mesoscale forcing mechanisms
for ascent moving through, so we`re not expecting widespread
precipitation at this time. However, diurnally driven storms may
be possible through the daytime hours Saturday. High
temperatures reach the low 80s. Overnight lows into Sunday fall
into the mid 60s with mostly dry conditions continuing.

The strength and positioning of the ridge continue to
contribute to the ongoing warming trend. Highs on Sunday reach
the low 80s, with low chances for an afternoon popup storm.

By the start of the work week, the secondary shortwave begins
to open up and move northeast with the surface system moving
northeast through the Plains. High clouds begin to build in on
Monday and precipitation chances begin to increase as the weak
cold front marches toward the region. Have Likely PoPs in for
Monday overnight into Tuesday, but overall forcing isn`t robust.

High temps anticipated to be only a tad cooler on Tuesday, with
highs in the upper 70s. Rain chances decrease in the post-
frontal air for Tuesday into Wednesday, but quickly return as
yet another shortwave begins to move toward the area in the
larger flow. Have periodic chances for PoPs in the forecast
through the remainder of the week in the unsettled pattern.

&&

.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --
High level clouds to continue to spill into the area today
as a mid level ridge builds across the area. As the ridge axis
shifts to the east moisture will increase late in the day into
this evening.

Clouds will thicken and lower while ceilings remain VFR this
afternoon as the mid level ridge axis shifts east and the flow
backs southwesterly.

The favorable lift will results in a band of showers and
embedded thunderstorms that pivots north thru the area late in
the day into this evening. Have a mention of VCSH for this pcpn
band but brief MVFR conditions will be possible in rain showers.

East winds at 10 kts or less early will become southeast at 10
to 15 kts this afternoon with gusts up to 20 kts.

OUTLOOK...MVFR conditions are possible on Saturday.
Thunderstorms are possible Monday night into Tuesday.
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&&

.ILN WATCHES/WARNINGS/ADVISORIES...
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OH...Frost Advisory until 9 AM EDT this morning for OHZ026-034-035-
     043>046-052>056-063>065-073-074.
KY...None.
IN...None.
-- End Changed Discussion --

&&

$$
SYNOPSIS...Hatzos
NEAR TERM...Coniglio/Hatzos
SHORT TERM...Hatzos
LONG TERM...CA
AVIATION...AR