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Area forecast discussion 
National Weather Service Wilmington Ohio
1002 PM EDT Thursday Jul 28 2016

Synopsis...
weak surface low pressure and a frontal boundary will remain
nearly stationary over the central Ohio Valley through Saturday
night. As these features interact with waves of energy aloft and a
persistent muggy airmass, showers and thunderstorms will be
possible at times through the weekend. High pressure will bring
drier conditions for Monday and Tuesday.

&&

Near term /until 6 am Friday morning/...
diurnally-driven showers and thunderstorms will continue to taper
off by midnight with further loss of daytime heating. Mid/high
level clouds from evening convection will linger through the
early overnight hours.

With a very moist low level environment, expect that patchy fog
will develop tonight, especially in areas that received
appreciable rainfall earlier today. Models continue to hint at the
development of a stratus deck for southern parts of forecast area late
tonight, which may inhibit widespread and/or dense fog.
Nevertheless, will need to monitor trends through the overnight as
a delay in stratus development may lead to more widespread fog
potential.

Both temperatures and dewpoints remain in the mid and lower 70s,
respectively, across the south this evening. With high dewpoints,
do not anticipate much of a drop in temperatures for the overnight
period, with forecast lows in the upper 60s in the north and
lower 70s in the south.

&&

Short term /6 am Friday morning through Saturday night/...
lingering weak surface low and frontal boundary over the region
will make for an unsettled weather pattern for Friday and
Saturday. As a broad upper trough slides over the Ohio Valley,
these surface features will interact with ripples of mid level
energy to generate showers and thunderstorms at times. Best
chances will be in conjunction with daytime instability both
Friday and Saturday. With only weak synoptic forcing and largely
unimpressive wind shear, the unorganized convection will be mostly
mesoscale driven. Have therefore blanketed the area with chance or
slight chance pops, highest during the peak heating hours both
days.

High temperatures for Friday and Saturday are forecast to remain
a few degrees below normal in the low to mid 80s due to clouds and
precip.

&&

Long term /Sunday through Thursday/...
weak frontal boundary will be moving through on Sunday. Moisture
will be limited with this feature and have only a slight chance of
thunderstorms in the forecast. High pressure and dry conditions are
expected for Monday into Tuesday across the region.

Some model solutions are showing a complex of storms working down
into portions of the area Tuesday night into Wednesday morning. The
best chance of precipitation with this appears to be across western
portions of the area. There have been some run to run
inconsistencies and the GFS is maintaining a dry forecast during
this time, therefore limited any precipitation chances to the chance
category at this time. The 12z European model (ecmwf) has come in drier for
Wednesday night into Thursday, which better corresponds with the
GFS. Due to this went with a dry forecast to only a slight chance
of storms during this time.

Better chances of precipitation look to hold off until after the end
of the long term period on Friday as a frontal boundary moves
through the region.

High temperatures will generally be in the 80s with low temperatures
in the 60s to around 70.

&&

Aviation /02z Friday through Tuesday/...
widely scattered rain showers/ts is expected to weaken this evening with
loss of diurnal heating. After activity dissipates, main concern
for overnight period is br/fog development, which is expected after
06z. Uncertainty exists in how cloud cover will evolve overnight,
especially in wake of evening convection, but expect that enough
radiational cooling will combine with very moist low levels to
allow for MVFR vsbys, with IFR vsbys or lower possible for
southern terminals. MVFR cigs may also develop toward the latter
part of the overnight period, especially for kcvg and kluk.

For Friday, the region will again be in a weakly forced and
unstable environment, leading to the potential for afternoon
shra/ts. Without focused forcing or a clear boundary across the
area, confidence remains low on timing and location of potential
activity. Nevertheless, still anticipate some development across
the area during the afternoon hours.

Calm winds tonight will be mainly light and variable Friday.

Outlook...thunderstorms possible Friday through Saturday.

&&

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

&&

$$
Synopsis...kurz
near term...kc/kurz
short term...kurz
long term...Novak
aviation...kc

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