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Area forecast discussion 
National Weather Service Wilmington Ohio
533 am EDT Wednesday Oct 7 2015

high pressure in the upper Midwest will move east and cross the
Ohio Valley tonight. Southerly flow will set up for Thursday ahead
of a cold front that will bring showers and possibly a
thunderstorm as it crosses the region early Friday. High pressure
will build north of the area Friday night and settle in the Ohio
Valley Saturday.


Near term /until 6 PM this evening/...
decided to err on the side of caution and put a dense fog advisory
out for northwest County Warning Area where a few observations are meeting the
criteria. Stratus deck including the fog will make a slow
progression to the south and will take some time to erode this
morning...hence the better practice of issuing an advisory this

Low stratus in Northern Ohio will continue to expand in area
slightly as it moves into the County Warning Area this morning. As Morning Sun
heats the ground this cloud deck will lift and scatter out in
favor of some stratocu and cumulus this afternoon with a stronger focus
in southern County Warning Area. Temperatures in the middle to upper 70s will be found under
a cooler light northerly flow and some cloud cover that is not
thin cirrus.


Short term /6 PM this evening through Saturday/...
low temperatures in the 50s tonight will increase slightly Thursday night
ahead of the front and lows will be fairly uniform in the lower
60s. This is after highs on Thursday approaching 80 with
increasing cloudiness. Showers Thursday night will be focused with
the frontal passage and increase a bit Friday with an added chance
for an embedded thunderstorm. Showers on Friday will limit high
temperatures to around 70 and high pressure behind the front will push
overnight lows into the 40s with rapidly clearing skies. Saturday
will be a tradeoff between the cold advection on northerly winds
and sunshine. Was hesitant to raise readings substantially...but
feel that it could reach upper 60s versus the lower 60s that are
currently in the forecast.


Long term /Saturday night through Tuesday/...
a cold front will move through the area on Friday. Models are in
agreement in having this feature move through and therefore
increased precipitation chances during this time. There are some
subtle timing differences. Went with the slower European model (ecmwf) solution and
linger precipitation into Friday night. There is only limited
instability on Friday and therefore kept thunder mention to a
slight chance during the daytime hours. With the slower European model (ecmwf)
solution have clouds lingering more during the overnight hours
Friday night and therefore did not go quite as cold with

With cold air advection expect cumulus to develop during the day on Saturday. Went
cooler than guidance on Saturday with the clouds and cool airmass in
place. There will be more clearing Saturday night and this will
allow temperatures to drop into the middle 40s across the entire forecast area.

Warm air advection and less cloud cover on Sunday will allow temperatures to
rebound into the upper 60s to around 70. There will be a gradual
warming trend through Tuesday. The European model (ecmwf) has a quick and weak
disturbance moving through Tuesday night and therefore added in a
chance of showers during this time.


Aviation /10z Wednesday through Sunday/...
broad high pressure will continue to drift into the region. Some
areas of ac will work across the northern tafs early this morning.
Meanwhile low level moisture could develop into some MVFR fog.
With mostly clear skies and light winds...kluk will be affected by
IFR valley fog this morning.

Any fog should lift by 12-13z...leaving the tafs under control of
the high. With northwest flow aloft...should see some scattered-broken ac affect
the region. A weak frontal boundary will eventually push into
the region by the end of the taf period.

Outlook...MVFR ceilings and visibilities possible Thursday night
into Friday.


Iln watches/warnings/advisories...
Ohio...dense fog advisory until 10 am EDT this morning for ohz026-034-
In...dense fog advisory until 10 am EDT this morning for inz050.


near term...franks
short term...franks
long term...Novak

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