Area Forecast Discussion Issued by NWS Wilmington, OH
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000
FXUS61 KILN 251318
AFDILN
AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
918 AM EDT Sat Jun 25 2022
.SYNOPSIS...
High pressure will move off to the east today as more humid air
begins to move northward. A cold front will approach the region
tonight, then move southeast through the region Sunday into
Sunday night. Showers and thunderstorms are expected to
accompany this system. High pressure will build back into the
Great Lakes and Ohio Valley for the beginning of the workweek,
offering cooler and drier conditions.
&&
.NEAR TERM /UNTIL 6 PM THIS EVENING/...
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Convection off to our northwest will continue to weaken as it
moves east into a less favorable environment. However, debris
cloudiness from this will continue to spill eastward into our
area as we head into this afternoon. This could help limit
temperatures a bit, especially across our northwest. In return
flow across the area though, we should still see highs into the
upper 80s to lower 90s. Some better lower level moisture will
push up into our southern areas through this afternoon, leading
to some increasing instability. This may be enough for some
isolated thunderstorm development toward mid afternoon for areas
along and south of the Ohio River.-- End Changed Discussion --
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.SHORT TERM /6 PM THIS EVENING THROUGH SUNDAY NIGHT/...
For tonight, diurnal isolated convection across our
south/southeast should wane by sunset. Aforementioned cold front
will continue its movement east. There seems to be a lack of
forcing overnight for maintaining convection to our west, so
will only allow for a low chance of showers/storms across the
northern/western zones. Clouds will increase. It will be warmer
and more humid with lows in the upper 60s to the lower 70s.
For Sunday into Sunday night, the cold front is expected to
move east/southeast through the region. This system is being
pushed along by a digging mid level trough into the Great Lakes
and southeast Canada. Upper support over the area seems to be
weak. However, ample moisture is forecast ahead of the front.
With enough breaks in the day, combined with weak low level
forcing, convective allowing models indicate the likelihood for
showers and thunderstorms, especially along and ahead of the
front during the afternoon and evening hours. Although overall
shear will be weak, MLCAPEs in the 1500-2000 J/kg range will be
enough fuel for thunderstorm development. The main hazardous
threats appear to be wind (DCAPEs approaching 700 J/kg) and
heavy rainfall (pwats of 2"+) as mid level lapse rates remain
poor for large hail. Will continue to mention the possibility
for strong to marginally severe thunderstorm winds along with
localized flooding. Later Sunday night, pcpn will come to an end
as the front pushes away, allowing for cooler and drier air to
filter into the region. It will be warm and humid on Sunday with
highs in the mid and upper 80s. Lows Sunday night will fall
back into the upper 50s to the lower 60s.
&&
.LONG TERM /MONDAY THROUGH FRIDAY/...
All indications are that a considerably drier and cooler air
mass moves in heading into early next week following the cold
front. A longwave trough pushing into eastern Canada noses
southward into the Great Lakes and Ohio Valley ushering in a
strong surface high pressure. SPC sounding climatology shows
that forecast 850 mb temperatures (7-8C) and PWAT values
(~0.50") will both be well below seasonal normals. These air
mass characteristics provide comfortable conditions both Monday
and Tuesday with temperatures in the upper 70s to low 80s along
with low humidity.
Surface high pressure weakens and shifts eastward on Wednesday
as a secondary shortwave trough digs into the Great Lakes. The
considerably dry air mass remains in place limiting the
potential for precipitation to reach far enough south to impact
the local forecast area. The high pressure shifting to the east
will allow for increasing temperatures Wednesday and into
Thursday, perhaps even into the lower 90s by Thursday. Humidity
levels also gradually increase Wednesday and Thursday as a pool
of moisture moves in from the north associated with the
weakening cold front.
The first chance for rain arrives late Thursday into Friday as
westerly upper level flow and the associated embedded shortwaves
advance far enough southward to enhance synoptic lift. At this
time, boundary layer moisture doesn`t appear too significant,
yet still enough to yield 1000-2000 J/kg. Given the subtle
nature of the forcing, details on severe weather threats and
timing are still quite low. Will stick with chance thunderstorms
for Friday and Saturday as the cold front moves through the
Ohio Valley over the course of the two days. Examining ensemble
solutions shows a range of speed differences with some
possibility for the front to be through the area by the holiday
weekend.
&&
.AVIATION /13Z SATURDAY THROUGH WEDNESDAY/...
For today, a mid level ridge axis will extend across the Ohio
Valley. Low level flow will begin to veer to a southerly
direction, allowing low level moisture to creep northward. This
should bring some afternoon cumulus clouds to KCVG/KLUK/KILN.
Deeper moisture and diurnal instability should keep any isolated
convection to the southeast of the terminals toward south
central Ohio and northeast Kentucky. Upstream convection will
result in mid and high clouds spilling southeast across the
region.
For tonight, considerable mid and high clouds are expected. The
mid level ridge axis will flatten as a cold front makes in
roads into our region from the west. There could be a
shower/storm near or after midnight closer to the northern
terminals. Too low of a threat at this time to mention.
OUTLOOK...Thunderstorms likely Sunday.
&&
.ILN WATCHES/WARNINGS/ADVISORIES...
OH...None.
KY...None.
IN...None.
&&
$$
SYNOPSIS...Hickman
NEAR TERM...JGL
SHORT TERM...Hickman
LONG TERM...McGinnis
AVIATION...Hickman