FXUS61 KILN 111940
AFDILN
AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
340 PM EDT Sun Apr 11 2021
.SYNOPSIS...
Low pressure will track east through the Lower Great Lakes and
keep some form of scattered shower activity in the Ohio Valley
through early Monday, then end from southwest to northeast
during the day. A weak ridge of high pressure will then lay out
from the Plains towards Kentucky through mid week, bringing dry
weather. Wednesday will see an upper low in the Great Lakes and
a surface low track from the Gulf states to the southeast,
possibly bringing the next chance of rain.
&&
.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
Cool air under a blanket of clouds will be found over the region
through the evening and overnight hours. Scattered to numerous
showers early on will become more scattered in the later evening,
ending from the southwest later overnight. Before they do
scatter out, two distinct areas will notably have a higher
propensity for rain this late day and early evening. One is
north of Dayton and will track due east. Another curves from
the northwest and skirts south of the Ohio River in Kentucky.
These areas may see a prolonged period of a steady rainfall for
the next few hours before insolation ends and they begin a
marked decrease this evening.
Temperatures will drop fairly uniformly into the 45-48 degree
range tonight and a continued southwest flow turning west at
10-15 mph.
&&
.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
The eastward moving surface low will see any rain lingering over
central Ohio in the morning quickly giving way to a more
scattered shower before ending. Not all of the models are in the
same camp and some linger additional shower activity on the
trailing edge of the cold pool later in the morning/early
afternoon. This seems possible but not as probable as a clearing
sky from w-e as the entire airmass tracks to the east early in
the day, being replaced with drier air and high pressure nosing
in from the west-northwest. Highs Monday will be near normal in
the low to mid 60s. Readings in the west and southwest could tip
towards 70 given a more sunny day than the remainder of the CWA.
Central Ohio could be a little warm with the forecast out attm.
readings in the lower 60s may end up only being in the upper 50s
if the shower activity and cloud cover does linger in this area
for a longer period of time.
Overnight will be clear to partly cloudy with lows dropping into
the lower 40s.
&&
.LONG TERM /TUESDAY THROUGH SUNDAY/...
A vertically-stacked cutoff low will continue to spin
north/northeast of the Ohio Valley Tuesday through Thursday
while the system slowly drifts towards the northeastern US. As
this occurs, surface high pressure will simultaneously try to
build into the Ohio Valley from the west despite the area being
on the southwestern flank of the upper-level low and possibly
the far western flank of the surface low. This messy synoptic
setup leaves the region in a regime with northwesterly/northerly
surface winds through the middle of the work week along with
sporadic chances for light rain showers and increased cloud
cover when occasional, low- predictability, vorticity maximums
rotate around the upper-level low. Northwesterly winds help keep
temperatures near seasonal norms for the middle of April
through Thursday.
By Friday,the upper-level cutoff low reaches the northeast
coast. This will likely result in the surface low translating to
the eastern seaboard in a region more favorable for
cyclogenesis. With the upper-level low and newly formed surface
low off the east coast, upper level ridging may briefly build in
over the Ohio Vally on Friday despite northerly surface winds
persisting along with seasonal temperatures and dry conditions.
Rain chances then increase for the weekend due to upper-level
ridging breaking down and the possibility of an upper-level
shortwave approaching.
&&
.AVIATION /19Z SUNDAY THROUGH FRIDAY/...
Low pressure center currently located in northern Indiana near
Lake Michigan will track east today and tonight. Wrap-around
moisture and cold air are being pulled in on the cyclonic flow
and will continue over the region through the next 24 hours.
Shower activity will peak later this afternoon as insolation
occurs, then wane this evening. Models continue to keep showers
over the region near the low, and TAFs will likely see a lower
MVFR to IFR cig and waffle on either side of the 1kft threshold.
VSBYs will likely remain VFR, and only drop to MVFR in a heavier
band. The banding of showers are being progged at different
locations, and TAF forecast will continue to keep VFR showers
and rain until the heavier bands form and begin to affect which
airport (if any) they train over.
Cold pool will linger over the region tonight and into Monday.
Shower activity will become more widely scattered overnight, but
a persistent nw-se oriented convergent zone is expected to
maintain shower activity overnight, and could hit DAY/CVG/LUK or
ILN. Actual location will likely be narrow, and odds of
impacting any one TAF site for more than a passing shower are
low.
OUTLOOK...No significant weather expected.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...Franks
NEAR TERM...Franks
SHORT TERM...Franks
LONG TERM...Campbell
AVIATION...Franks
