Area Forecast Discussion
Issued by NWS Wilmington, OH

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FXUS61 KILN 211803

Area Forecast Discussion
National Weather Service Wilmington OH
203 PM EDT Fri Oct 21 2016

Low pressure will continue to move northeast today slowing pulling
the backedge of the rain eastward with it. A much colder airmass
will filter into the region today and Saturday, before warmer air
works back into the region for Sunday.


Upper level trof axis along the Indiana/Ohio border to push east
thru the Ohio valley today. Wrap around rain, associated with
deformation zone to end precipitation from west to east across
ILN/s FA through mid afternoon. Temperatures will be cooler today
with highs ranging from the lower 50s north to the upper 50s

Previous discussion...
The center of low pressure and a cdfnt are located over West
Virginia early this morning. This has allowed winds to turn to the
north and temperatures to fall into upper 40s and 50s. However,
sharp H5 trof will swing thru the fa this morning. This is
combining with a deformation axis to produce a secondary band of
rain across IN into wrn OH.

It will take a good part of the morning for deformation zone to
work thru the fa, and to bring an end to the chance of rain. Some
rain could linger in the extreme eastern counties into early

Strong pressure gradient on the backside of the low will keep
winds gusty, especially this morning. Gusts 20-30 mph will be
possible. CAA will persist through the day with 850 mb
temperatures dropping down below 0C by late afternoon. This will
counteract the drier air trying to build in this afternoon, to
linger the clouds today. With the cloud cover, temperatures
will be limited to the lower to mid 50s, with a few spots in the
Cincy Tri-State making the upper 50s.


By 00Z the H5 trof axis will be into the Appalachians, leaving
the fa in nw flow both at the sfc and aloft. Feel that there will
be enuf cold air aloft to linger the clouds overnight. The clouds
will help keep temperatures up a little, but they still be a
little below normal falling in the upper 30s and lower 40s.

Surface high pressure will begin to build up into the Tennessee
Valley. While this keep dry conditions on Saturday, lingering cold
air aloft will allow for clouds to redevelop especially during the
afternoon. This will keep temperatures in the 50s, ranging from
the lower 50s in the east to the mid 50s in the west.

Saturday night will see H8 temperatures warming, but think that
the atmosphere will decouple enough for a small diurnal drop in
temperatures. Lows Saturday night will drop back into the lower to
mid 40s.

On Sunday, southwest winds at the sfc will bring warm air back
into the region. A few high clouds could affect the region in fast
flow aloft, but there will be plenty of sunshine and temperatures
should make the mid to upper 60s for highs.


Sunday night into Monday morning a shortwave will push southeast
down mid-level ridging and around the upper level low. The GFS is
slightly more progressive and weaker with the shortwave compared
to the ECMWF. Both 20.12z model runs bring the shortwave slightly
further west than yesterday and therefore try to bring the heart
of the colder air slightly further west as well. The ECMWF and the
GFS push the front through the area by Monday evening. The frontal
passage also appears to be a dry frontal passage as PWATs remain
around 0.60". Behind the front highs will cool down back to normal
as the heart of the cold air still misses the area (850 mb
temperatures around 4 degrees C).

Tuesday the upper level trough will finally head east of the area
taking the cooler air with it. Wednesday into Thursday a shortwave
will eject out of the midwest and approach the area. This means
clouds will begin to increase on Wednesday and into Thursday. Have
also introduced a chance of rain into the forecast Thursday as the
low approaches. PWATs on the GFS rise to above 1.00" with limited
instability. Upper level forcing looks good though as the ILN
forecast area is in the diffluent side of the trough axis and
widespread PV moves over the area. For now have just edged the
chance of precipitation up as model consistency remains low at this


As upper level trof pivots through the Ohio valley, rain is
coming to an end from west to east. MVFR CIGS are improving to VFR
across the west, as clouds lift to around 4000 feet. MVFR CIGS
will linger a little longer at KCMH/KLCK with VFR conditions not
expected until 00z. Broken VFR CIGS are expected to continue
through the night with clouds scattering out at times. CIGS
between 3500 and 4000 feet are expected to continue through the
TAF forecast, with clearing holding off til late Saturday

Northwest winds will gust up to 25 kts this afternoon and
then continue from the northwest at speeds up to 10 kts tonight
and 10 to 15 kts Saturday.

OUTLOOK...No significant weather expected.




LONG TERM...Haines
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