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Area forecast discussion 
National Weather Service Wilmington Ohio
433 PM EDT Tuesday Jul 22 2014

Synopsis...
an approaching cold front will continue to keep southwest winds
and humid air over the Ohio Valley ahead of it. This front will
push through the region Wednesday and spark a round of showers
and thunderstorms. A large area of high pressure will build behind
it and provide dry and cool weather through the end of the work week.

&&

Near term /until 6 am Wednesday morning/...
fair weather cumulus field will dissipate this evening and the isolated
shower southeast of metropolitan cincy had already rained itself out. The
favorable area for another weak isolated shower from Georgetown
East and south will likely not support any showers but a low
chance pop continues this evening in this area.

Temperatures will be on a slow drop as in previous evenings with the high
dewpoint air remaining in place. Expect a muggy low around 70 for
much of the region tonight.

&&

Short term /6 am Wednesday morning through Thursday night/...
cold front is being prognosticated with a continuously faster solution
with each model run. In the northwest County Warning Area at 12z it is well southeast of
the I-71 corridor by 18z. Precipitation in the cold pool behind the wind
shift will be hard pressed to see damaging winds with any
convective elements and the swody2 outlook appears to whittle away
at the severe prospects with each discussion. At this moment...I
would expect a rainy period with thunder but the lack of distinct
strong cores/updrafts necessary for wind/hail. Elevated
instability will make for occasional downpours and winds when
these elevated cores collapse...but the expected high moisture and
cold nature of the air in the boundary layer would limit any very
strong winds from occurring.

Highs were prognosticated to be a bit warmer than I would expect in the
southeast with a grungy day of cloud cover. Lowered readings a bit
to top out at 90 degrees as a maximum and think that this would be
an early afternoon high with strong advection from a sunny pocket
over Kentucky being pulled into my northern Kentucky and southeastern Ohio counties. Northwest County Warning Area
will be thoroughly grunged and not reach past the 70s.

After precipitation ends tomorrow night...high pressure will push in
drier and cooler air to the Ohio Valley and this will remain in
place through the end of the work week.

&&

Long term /Friday through Tuesday/...
surface high pressure will be centered across the Ohio Valley on
Friday. This high will quickly slide southeast of our region and
weaken as an upper level disturbance embedded in northwesterly
flow approaches our region. Models have accelerated the arrival of
this disturbance...yet still vary by several hours on their
forecast arrival of precipitation on Saturday. Added low chance
probability of precipitation early Saturday morning with probability of precipitation ramping up into the day
Saturday based on the faster trend. Kept only chance probability of precipitation on
Saturday due to timing and coverage uncertainties for
precipitation on Saturday. Temperatures under the high on Friday
will remain a few degrees below normal. Once the high shifts to
our southeast...a rebound to near normal temperatures can be
expected for Saturday.

On Sunday...a unseasonably deep trough is expected to dig
southeastward across the middle west and into the Ohio Valley. Low
pressure downstream of this trough will drag a cold front across our
area. The CMC and GFS are in fairly good agreement on bringing
enhanced chances for precipitation to our area on Sunday ahead of
this front...with the cold front crossing our area at some point
late Sunday. Best chances for precipitation appear to be during the
day Sunday in the warm sector...with cooler air moving into the
region by Monday. The trough is forecast to remain in the region
through the early parts of next week. Models vary on how much
moisture lingers behind the front. Am forecasting mainly low chance
diurnally driven showers and isolated thunderstorms in the cold
sector. This high amplitude trough will bring another round of well
below normal temperatures to the Ohio Valley early next week...with
current indications being that highs may only reach the lower 70s on
Monday and possibly again on Tuesday.

&&

Aviation /20z Tuesday through Sunday/...
diurnal cumulus across the tafs might go broken at times this afternoon
at the eastern tafs before dissipating towards sunset.

Models are then consistent in bringing cold front down into the tafs
after 06z...draping it across the region by 12z. It appears that
the consensus of the models is to produce precipitation Post frontal with
the system. It appears that the convection could get going better
during the afternoon hours southeast of I-71 where the lingering instability
would be higher.

So...kept the mention of thunderstorms and rain as a vicinity for the northern tafs. At
cvg/luk increases the precipitation chances to prevailing around 17z with
some MVFR visibilities.

Outlook...thunderstorms possible Saturday and Sunday.

&&

Iln watches/warnings/advisories...
Ohio...none.
Kentucky...none.
In...none.

&&

$$
Synopsis...franks
near term...franks
short term...franks
long term...latto
aviation...sites

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