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000
FXUS61 KILN 221853
AFDILN

Area Forecast Discussion
National Weather Service Wilmington OH
253 PM EDT Fri Sep 22 2017

.SYNOPSIS...
A mid-level ridge of high pressure will remain over the region
through early next week. This will bring generally dry and warm
weather conditions to the region. A slight cooling trend will
occur by the middle of next week.

&&

.NEAR TERM /THIS EVENING/...
Stagnant. Probably the best word to describe the weather
pattern over the Ohio Valley the past few days, but the warmth
is another part of the story. NWS ILN has reached 91 degrees
today and several other observation sites have either also
gotten there or should in the next hour or two.

Satellite imagery shows the greatest extent of cumulus
development has been across Indiana and into west-central Ohio,
along the fringes of the ILN CWA. Showers have developed in this
area as well, which appears to be associated with an axis of
slightly higher dewpoints (upper 60s to lower 70s). Over the
next few hours, there will still be a slight chance of activity
in the ILN CWA, mainly in the far southwestern / western
sections.

As skies clear and dewpoints drop slightly, min temps should
actually get slightly lower than last night -- lower to middle
60s are expected.

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
There will be little change in the pattern going into Saturday,
aside from a slight northward shift of the ridge, but a couple
of minor differences in the overall scenario. There is
definitely a trend toward a drier air mass, with dewpoints
falling into the mid 60s and precipitable water values dropping
to closer to an inch than an inch and a half. This should
effectively end any chance of pop-up diurnal showers, and in
fact it would not be surprising to see most of the area remain
clear on Saturday. The other issue is that with full sun and
850mb temperatures slightly rising from Friday to Saturday,
temperatures may actually end up even warmer than on Friday (or
even warmer than currently forecast for Saturday). This set of
grids includes a slight increase from the previous run, allowing
for close to 90 for the whole CWA. Based on conditions today,
this could be conservative by a degree or two.

Again, no big change going into Saturday night, so min temps
will be similar (or just slightly lower with less moisture) to
values on Friday night.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
Large H5 ridge over the eastern U.S. continues to dominate the
region`s weather pattern at the beginning of the period. It will
combine with a surface high centered over the eastern Great Lakes to
bring dry and much above normal temperatures to the region for the
first half of the period. High temperatures in the upper 80s Sunday
and Monday, will drop back into the mid 80s for Tuesday. With normal
highs in the mid 70s, the forecast highs will be about 10-15 degrees
above normal. Morning lows be in the lower 60s.

By Wednesday, the models bring a cold front through the Great Lakes.
The 00Z ECMWF is weaker with the H5 s/w. The GFS is a little
stronger and more amplified with this feature and is supported by
the ECENS means, along with the 06Z GEFS. So brought chance PoPs of
showers and thunderstorms across the region Wednesday.

Behind the front, a major pattern changes takes place as the H5
ridge in the ern U.S. is replaced with a trof. This brings in more
of a seasonal airmass. Highs on Thursday will be down into the 70s,
with Friday`s highs ranging from the mid 60s to lower 70s. With the
CAA aloft, there could be some isolated light showers each day.

&&

.AVIATION /18Z FRIDAY THROUGH WEDNESDAY/...
VFR conditions are expected through the TAF period, with calm or
very light winds. Diurnal cumulus today will dissipate, and
skies should remain clear to mostly clear through tomorrow.

Fog appears less likely tonight than the past few days, so
visibility restrictions were not included in the TAFs. The
exception is for valley fog (MVFR/IFR) at KLUK.

There is a very slight chance of a shower developing this
afternoon at KDAY/KCVG/KLUK but much too low to include in the
forecast.

OUTLOOK...No significant weather expected.

&&

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

&&

$$
SYNOPSIS...Hatzos
NEAR TERM...Hatzos
SHORT TERM...Hatzos
LONG TERM...Sites
AVIATION...Hatzos