Area Forecast Discussion
Issued by NWS Wilmington, OH-- Highlight Changed Discussion --
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FXUS61 KILN 282352
Area Forecast Discussion
National Weather Service Wilmington OH
752 PM EDT THU JUL 28 2016
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/...
Another round of light rain will clip the southeastern part of
the ILN CWA this afternoon and push out of the area early this
evening. Rainfall rates have not been impressive over the last
several hours, and there has been very little if any thunder with
this afternoon`s activity. Have therefore opted to cancel the
flash flood watch. There have been some pulsy surface-based
showers/storms popping up across the region over the past few
hours, but the individual cells will not last very long and this
diurnal activity is expected to wane towards sunset. Most models
have our area dry for the overnight, but the main question will be
how much cloud cover will stick around. Satellite shows the clouds
starting to thin out across our west, and there is some clearing
over Indiana now that will be moving into our west. With abundant
low level moisture, there will likely be some stratus that
develops overnight. How expansive it may become is still
uncertain. If the stratus doesn`t become too prevalent, fog could
be an issue, especially for areas that saw rainfall since last
night. For now have put patchy fog in the wx grids to account for
this possibility, but evening shift will be monitoring. Lows
tonight will range from mid 60s north to near 70 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
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
.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 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 /00Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --Widely scattered SHRA/TS is expected to weaken this evening with
loss of diurnal heating. After activity dissipates, main concern
for overnight period is BR/FG 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.
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