Area Forecast Discussion Issued by NWS Wilmington, OH
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FXUS61 KILN 290527
AFDILN
AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
127 AM EDT Fri Mar 29 2024
.SYNOPSIS...
A weak warm front will bring clouds and a few showers to parts
of the region tonight. Dry and warmer weather is then expected
on Friday. Another warm front will move into the region Friday
night into Saturday, bringing a greater threat for showers and a
few thunderstorms.
&&
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
A weak disturbance along with an
associated westerly low level jet will continue to provide for
scattered light showers overnight. Dry air near the surface will
limit the precipitation to mostly sprinkles or virga. Activity
will decrease from west to east as the night draws to a close.
Temperatures will slowly fall into the upper 30s to near 40
degrees.
&&
.SHORT TERM /6 AM THIS MORNING THROUGH 6 AM SATURDAY/...
Any shower
activity should be over with and out of the area by sunrise
Friday as the low level jet pivots off to the east/southeast.
For Friday, the weak boundary will remain across the northern
half of the CWFA. But with some weak ridging to the north and
south of this boundary, and not much in the way of any forcing,
it should remain dry with partly to mostly sunny skies. West
winds will increase some with gusts between 15 and 25 mph
possible. It will be warmer with highs ranging from the lower
60s northeast to near 70 southwest.
Chances for showers and few thunderstorms will increase Friday
night as a mid level s/wv moves into the Great Lakes from the
west. An associated low level jet will focus low level forcing
into the region along a warm front which will act as the impetus
for increasing showers and storms. The best chance will be
across the west central Ohio region with lesser chances as one
heads south of the Ohio River. It will be mild with lows in the
upper 40s to the lower 50s.
&&
.LONG TERM /SATURDAY THROUGH THURSDAY/...
Midlevel ridging will develop and nudge E into the OH Vly for
the first half of the long term period, prompting broader deep-
layer WAA/theta-e advection and weak isentropic lift as several
midlevel waves move E through the region.
By late Friday night through Saturday morning, an embedded S/W
will eject E from the mid MS Rvr Vly into the OH Vly, promoting
stronger lift along the nose of a strengthening LLJ nudging to
the NE through the region. This will allow for better
moisture/mass convergence to develop/expand, leading to the
development of a narrow corridor of SHRA extending ESE from nrn
IL through nrn/central IN and nrn/central OH by Saturday
morning. There appears to be relatively good agreement in the
model suite with regards to this feature, with only subtle
latitudinal variability in the solutions at this time. Feel
confident continuing likely/categorical PoPs for the nrn half or
so of the ILN FA Saturday morning before slightly drier
conditions evolve by afternoon/evening as the main system pulls
E of the region, leaving the dangling baroclinic zone arcing
back to the WSW.
This initial wave, upon its departure Saturday evening, should
push the aforementioned boundary S to closer to/S of the OH Rvr
as drier air briefly builds in behind the first sfc wave
Saturday night/early Sunday. This should allow for drier,
although perhaps not completely dry, conditions Saturday
evening/night. However, this boundary will begin to stall and
lift back N once again by Sunday morning/afternoon. This will
promote renewed convective development Sunday as directional
convergence increases near the WNW-ESE oriented front,
sharpening the baroclinic zone further. This will coincide with
more aggressive moisture transport back N into the region, with
PWAT anomalies potentially exceeding 175% of normal, by Sunday
night. With all of this, another round of rain/storms (with some
low-end instby being shown on much of the prevailing guidance)
should blossom about Sunday afternoon through the night,
initially near/S of the I-70 corridor. With the steering-layer
flow oriented more parallel to the forcing mechanism (the quasi
WNW-ESE oriented baroclinic zone), the potential for heavy rain
and training of convection may evolve Sunday and will need to be
watched carefully for the onset of hydro concerns, even with
the antecedent dry conditions for much of the area.
We should continue to see a northward pivot in the boundary
through early Monday, with more of the local area becoming
situated squarely in the warm sector of the eastward-moving
system, which should eject through the central plains into the
mid MS Rvr Vly by Monday afternoon. Renewed rain/storm chances
will occur once again late Monday/Monday night/Tuesday morning
with the better forcing and additional lift spreading E ahead
of/along the front, with the primary system moving through the
region at some point late Tuesday.
There are several items to watch regarding the pattern this
weekend into early next week -- most notably the repeated rounds
of rain and whether the heaviest activity from each "round"
moves over the same areas more than once. Although the ILN FA
has seen drier-than-normal conditions recently (especially in
the last 14 days) and streamflow is generally running below
normal, persistent training of convective activity could lead to
isolated flooding. Still a bit too far out to isolate one
specific favored area/corridor for heavy rain, but it is
mentioned here for general awareness purposes, especially
considering the anomalous moisture content in the profile and
the cumulative effect of several rounds of steady/heavy rain as
we progress into Monday/Monday night/Tuesday morning. The other
item will be the potential for a few strong/severe storms late
Monday/Monday night. The overall setup, from a pattern
recognition perspective, certainly suggests that severe storms
may develop in/near the local area if the necessary ingredients
come together, especially in a scenario with a
strengthening/deepening sfc low darting to the NE through the
wrn OH Vly. And if a more wide-open (further north) warm sector
is able to develop Monday afternoon/evening, allowing for a
better/more favorably-widespread LL thermodynamic setup, amidst
seasonably strong deep-layer wind fields, a few strong to severe
storms could evolve. As of right now, the most concerning time
period for a few strong to severe storms may be Monday
evening/night, but there are still quite a few spatial and
temporal details that need to be ironed out. Will continue
broad- brushed mention in the HWO for now, with additional
details to be added in subsequent forecast updates.
Drier and cooler conditions should return beyond midweek next
week.
&&
.AVIATION /06Z FRIDAY THROUGH TUESDAY/...
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Scattered light rain showers will drift southeast across the
region through daybreak but should have minimal operational effects
on the TAF sites. Pcpn will taper off through mid morning with
mid and high level clouds affecting the area at times through
the remainder of the TAF period. A developing low level jet
will lead to the possibility of some LLWS late tonight into
early Saturday morning.
OUTLOOK...MVFR conditions possible Saturday. MVFR/IFR
conditions along with a chance of thunderstorms possible Sunday
through Tuesday.-- End Changed Discussion --
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...Hickman
NEAR TERM...
SHORT TERM...Hickman
LONG TERM...KC
AVIATION...JGL