718
FXUS61 KILN 262335
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
735 PM EDT Fri Apr 26 2024

.SYNOPSIS...
As surface high pressure moves off the east coast, a warm front
will move into the Ohio Valley tonight. Rain is expected for
some locations tonight, with a warming trend heading into the
weekend, and generally dry conditions. The chances for showers
and storms will increase next week.

&&

.NEAR TERM /UNTIL 6 AM SATURDAY MORNING/...
Surface high pressure over New England is continuing to move
east, as a mid-level ridge axis moves eastward into the Ohio
Valley. The boundary layer has begun to moisten, with dewpoints
in the 40s across much of the ILN CWA now. However, temperatures
in the 70s mean that RH values remain fairly low. This will
make precipitation somewhat of a challenge later this afternoon
and tonight, as both boundary layer and deep-layer saturation
are rather marginal. A broken band of precipitation currently
extends from south of Chicago to north of Nashville. Eventually,
some of this precipitation will pivot northeast into the ILN
CWA, but the trend toward sparse coverage of measurable
precipitation has continued to be evident on recent model runs.
PoPs will be reduced slightly, now mainly in the 20-40 percent
range tonight. There are some CAM indications of another area of
showers or even weak convection making it into the northwestern
ILN CWA after 06Z, so this will be accounted for in the grids
as well. By morning, the southern and southeastern sections of
the forecast area are most likely to be dry.

With southerly winds staying in place overnight, temperatures
will remain somewhat mild, with lows in the upper 50s to lower
60s.

&&

.SHORT TERM /6 AM SATURDAY MORNING THROUGH SATURDAY NIGHT/...
By 12Z Saturday, the entire ILN forecast area will be solidly in
the warm sector, with an increasing pressure gradient and
deeper boundary layer mixing helping to bring wind gusts into
the 25-35 MPH range. This warm advection pattern will also make
for a warm day, with highs in the middle to upper 70s.

With no real discernible surface or mid-level features over the
ILN area, forcing will be very limited on Saturday, so
precipitation chances are low. Any isolated activity would be
more likely to develop closer to the stronger southwesterly
mid-level flow, so perhaps in the far northwestern ILN CWA near
diurnal timing.

&&

.LONG TERM /SUNDAY THROUGH FRIDAY/...
Continued ridging in place over the region at the start of the
period, with strong southerly flow into the Ohio Valley for
Sunday. Temperatures push into the low/mid 80s with partly
cloudy skies. Ample moisture will be present (given this time of
year) but with Tds in the upper 50s, it shouldn`t feel too
muggy out. Outside chance for an afternoon diurnally driven
popup storm but no real forcing for ascent present, so left PoPs
dry for the time being. Sunday night remains dry, with lows in
the mid 60s.

By Monday, we`ll finally have a bit of a pattern shift as an
upper level shortwave near the N. Dakota/ Minnesota border
swings through the larger flow, nudging the ridge east out of
our area. At the surface, a low pressure moves through the
western Great Lakes, dragging a relatively weak cold front
through our region. Showers with some embedded thunder arrive
Monday evening through Tuesday, decreasing in coverage by
Tuesday afternoon. Highs on Tuesday a tad cooler, in the
mid/upper 70s. Otherwise, temps/Tds rebound quickly as another
shortwave rides along the heels of the first.

This pattern results in a more zonal upper level structure,
with repeated shortwaves moving through the flow. Therefore kept
at least chance precip in the grids off and on through the
remainder of the working week, despite lack of consensus on
exact path of the waves.

There does seem to be a decent signal in above average
temperatures through the week, with highs nearing 80 most days,
about 10 degrees F above normal.

&&

.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
While VFR is expected to persist, aviation will be affected by
wind shear of 40 to 45 knots and surface gusts over 20 knots
ahead of low pressure to the west. Though isolated showers
forming near a warm front may not directly impacts airports,
VCSH are forecast for DAY LCK and CMH. Otherwise we can expect
mid level ceilings that will dissipate on Saturday as the warm
front moves north. Winds should subside near the end of the
forecast period as the pressure gradient in the warm sector
relaxes.

OUTLOOK...Thunderstorms are possible at times on Monday,
Tuesday, and Wednesday.

&&

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

&&

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