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844
FXUS61 KILN 221954
AFDILN

AREA FORECAST DISCUSSION
National Weather Service Wilmington OH
354 PM EDT Sun Sep 22 2019

.SYNOPSIS...
A cold front will approach the area tonight and move through on
Monday. High pressure will build in for Tuesday and Wednesday.
Heat will build back into the region at the end of the week.

&&

.NEAR TERM /UNTIL 6 AM MONDAY MORNING/...
A cold front will approach the area tonight. Clouds will
increase, especially after midnight. Showers will spread into
the area as well. It looks like coverage will be greater across
the Whitewater and Miami Valleys. Cannot rule out a rumble of
thunder. Tightening pressure gradient will keep winds up through
the night. This will help keep low temperatures in the upper 60s
to lower 70s.

&&

.SHORT TERM /6 AM MONDAY MORNING THROUGH MONDAY NIGHT/...
Prefrontal showers will diminish as they continue east across
the forecast area early in the day. Another band of showers and
possibly a storm may accompany the actual cold front which will
move through the area between 12Z and 18z. Clouds will decrease
in the afternoon and early evening but there will be some gusty
post frontal winds for a period of time. High pressure will
build in late in the period.

There will be a limited rise in temperatures where the front
moves through early in the day with some heating still possible
ahead of the front in southeast counties. So highs will range
from the mid 70s to around 80. Lows will be able to drop off to
closer to normal Monday night.

&&

.LONG TERM /TUESDAY THROUGH SUNDAY/...
The FROPA through the region on Monday will allow for drier air to
infiltrate the Ohio Valley for the start of the long term period --
with near normal to slightly above normal temperatures from Tuesday
through Thursday. This will occur coincident with surface high
pressure briefly building into the region followed by a secondary
weak frontal passage Wednesday night into early Thursday morning.

While certainly this secondary/midweek FROPA could deliver another
round of isolated to scattered showers to the area -- as of right
now, it does appear that the forcing and moisture availability will
be rather meager. Only right along/ahead of the front is the
moisture return likely to be sufficient enough to support a few
showers -- but this corridor/stripe of better moisture will be
rather narrow and transient. This would tend to suggest for the
front to progress through the area with just some chance PoPs at
best before drier conditions once again return by Thursday
afternoon. The front will be accompanied by a more noticeable return
of dry air opposed to inherently cooler air. In fact, dewpoints will
fall again into the lower/mid 50s by late Thursday with clearing
conditions through the day.

By the end of the workweek into the upcoming weekend, longer range
guidance remains in very good agreement showing fairly strong quasi-
zonal mid/upper level flow transitioning to anomalously expansive
ridging initially across the southeastern U.S./Carolinas late in the
workweek before overspreading pretty much all of the Tennessee/Ohio
Valleys by next weekend. This will occur coincident with digging S/W
energy into the Pac NW and an ejecting system from the desert
southwestern U.S. -- both of which will act to amplify the overall
flow pattern across the rest of the U.S. The increasing meridional
pattern /aided in part by the rapid deepening of the upper low along
the west coast/ will induce tremendous height rises along/east of
the Mississippi River Valley by this upcoming weekend with
corresponding troughing across much of the west. While there are
some natural discrepancies that exist in longer range solutions --
specifically as they relate to exact positioning of the center of
the ridge -- there remains above normal confidence in another period
of very warm temperatures setting up by the end of the long term
period and even into the first part of the next week. The
persistence of several/many deterministic and ensemble solutions
showing this highly-amplified pattern lends itself to high
confidence in above to even much-above normal temperatures to close
out the month next weekend into the following week. In fact, EPS
mean H5 heights approaching 2 standard deviations continue to be
advertised across the Tennessee Valley about 7 days from now, with
H8 temps 8C to even 10 C+ above normal. Many solutions show some of
the most robust/anomalous heights/temps setting up squarely
over the OH/TN Valleys. And it should be mentioned that this
type of pattern, should it evolve in such a manner, would
suggest the potential for record or near record temperatures to
close out the month. Of course, the specifics of the pattern
which will ultimately dictate the sensible weather locally will
still be coming into better focus in the coming days. However,
confidence is increasing in the potential for several days with
daily temperatures 15+ degrees above normal for the final part
of September -- with even some more 90- degree days not out of
the realm of possibilities.

&&

.AVIATION /20Z SUNDAY THROUGH FRIDAY/...
Gusty south southwest winds will diminish towards 00Z. It will
be VFR with just a few cumulus. Clouds will increase ahead of a
cold front but remain VFR until around 09Z. Scattered showers
will occur and ceilings will fall to MVFR, likely getting below
2000 ft. A cold front will cross the terminals between 12Z and
18Z. Ceilings will lift above 2000 ft and perhaps even become
VFR very late in the period at some locations.

OUTLOOK...MVFR ceilings may linger into Monday afternoon.

&&

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

&&

$$
SYNOPSIS...
NEAR TERM...
SHORT TERM...
LONG TERM...KC
AVIATION...