Area Forecast Discussion
Issued by NWS Wilmington, OH-- Highlight Changed Discussion --
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FXUS61 KILN 300538
Area Forecast Discussion
National Weather Service Wilmington OH
138 AM EDT SAT JUL 30 2016
A weak frontal boundary will remain across the region through
much of the weekend, leading to chances for showers and
thunderstorms at times. High pressure and a drier airmass will
build into the Ohio Valley on Monday and Tuesday.
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Weak frontal boundary stretching from southern IL to northern OH
continues to trigger scattered convection across the region this
afternoon. Once again this afternoon conditions are favorable for a
few brief needle-like funnel clouds to develop: stationary
boundary, very weak wind shear and low level winds, steep low-
level lapse rates, and rich low-level moisture. Have this
mentioned in HWO but will consider an SPS if we start
seeing/receiving funnel reports. MLCAPEs are around 1000 J/kg, but
mid-level lapse rates are providing some limit to storm strength
this afternoon. Would not rule out a stronger storm with gusty
winds through early evening, but overall severe threat will be
limited. With rather weak upper flow and a rich supply of low-
level moisture (PWATs around 1.7"), storms have been slow-moving
and producing heavy rainfall. This will lead to a continued
localized flooding threat through this evening, when storms are
expected to diminish in coverage.
Held on to a chance/slight chance of showers and storms
overnight as some shortwave energy pushes through the region.
There will be a chance for fog and low stratus development once
again later tonight with lows ranging from the mid 60s north to
upper 60s south.
.SHORT TERM /6 AM THIS MORNING THROUGH SUNDAY NIGHT/...
With the boundary still lingering over the region this weekend and
a broad upper trough moving in, expect a few rounds of scattered
showers and thunderstorms. Most of this will be diurnally driven,
and Saturday looks like the wetter and cloudier of the two days
with better mid-level forcing. Weak mid-level lapse rates will
again provide some limit to storm intensity. By Sunday night the
upper trough axis will begin pushing east, and drier air will
begin filtering into the region. Highs both Saturday and Sunday
will be in the low to mid 80s.
.LONG TERM /MONDAY THROUGH FRIDAY/...
Period begins with a weak H5 trof over the Great Lakes. In the
localized nw flow, the models are dropping weak s/w into the region.
The models are handling these weak disturbances differently and
therefore are producing a variety of solution. The GEM hemispheric is
the most aggressive as it drops a MCS thru IN and KY nicking the
Tri-State region with pcpn. The GFS and to a less extent the 12Z
ECMWF pop a little QPF along the Ohio River. The 00Z ECMWF was dry.
Confidence is too low that the models have a handle on the
situation so will continue to carry a 10 PoP in the south and less
to across the nrn counties, therefore going dry. It looks like highs
will be in the lower and mid 80s.
H5 ridge builds in Monday night and Tuesday, which should keep the
fa dry and mostly sunny. Temps will warm a couple of degrees with
highs on Tuesday, into the mid and upper 80s.
ECMWF continues to be the outlier, as it drops an MCS out of MN and
down towards the fa Tuesday night, then bringing it across the fa
Wednesday. The ECMWF has showing this for a couple of runs now. Will
go with a 20 PoP to show the possibility. Hopefully future runs will
bring the models into better agreement. Kept highs on Wednesday in
the mid to upper 80s.
Thursday looks like another dry day, then a cdfnt will start to drop
towards the area for Friday. An increasingly unstable atmosphere
with interact with the forcing from the front to bring a chance of
thunderstorms on Friday.
.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
-- Changed Discussion --Showers and thunderstorms have started to come to an end this
morning with the only remaining coverage affecting the Columbus
terminals. This should dissipate soon as the loss of daytime
heating will help to limit coverage. This morning skies will try
to clear a bit from west to east allowing for the chance of fog to
return to the terminals. Towards IND skies have already cleared
some with reduced visibilities being reported. Our western
terminals will have the greatest chance of fog with a slightly
lower chance for the eastern terminals as it will take longer to
During the day today an upper level low will remain just west of
the area bringing another chance of rain. GFS and NAM forecast
soundings show PWATs slightly falling today but still are elevated
for this time of year. Instability is also supportive of more
showers and thunderstorms with k indicies in the mid 30s. Looking
at high res models the highest chance of precip will be just off
to our east today. This makes sense given the position of the
low. Have added vicinity into all of the TAFs but think the best
chance will be at KCMH/ KLCK due to them being further east.
Showers and thunderstorms will then again come to an end this
evening as the sunsets and daytime heating is lost.
OUTLOOK...Slight chance of thunderstorms Sunday.
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