Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
1122 am EDT Sat Jul 30 2016
a chance for showers and thunderstorms will persist through the
weekend as a frontal boundary will remain stalled across the
region. Temperatures will remain seasonable through the first of
Near term /until 6 PM this evening/...
updated the forecast to delay precipitation onset. A few light
showers will be possible this morning, however with the lack of
sunshine temperatures have been delayed and have delayed any
convection. Lowered temperatures a couple of degrees across some
areas today, however did not want to lower too much at this point
because any breaks in the clouds will allow for a quick rise in
temperatures. Isolated to scattered convection will still be
possible by later this afternoon. The best chance for heavy rain
and slow moving storms will be across northern portions of the
forecast area, especially across central Ohio.
Short term /6 PM this evening through Monday/...
there should be a downward trend in thunderstorm coverage heading
into this evening as they will be diurnally enhanced. However,
with the mid level trough axis still moving through, will just
taper back to a 20 pop through the overnight hours. The better
energy will then continue to shift east through the day on Sunday.
Will continue with lower end pops, with the best chance across
eastern portions of our forecast area during the afternoon hours.
We will remain in northwest flow aloft Sunday night into Monday
with some models suggesting some possible short wave energy
dropping down toward our area. There is some uncertainty with the
timing and placement for this though. Would think the best chance
for anything would be across southern portions of our area but
given the uncertainty, will maintain a dry forecast for the time
Highs both Sunday and Monday will be in the low to mid 80s.
Long term /Monday night through Friday/...
period begins with a weak 500 mb 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 mesoscale convective system thru in and Kentucky nicking the
tri-state region with pcpn. The GFS and to a less extent the 12z
European model (ecmwf) pop a little quantitative precipitation forecast along the Ohio River. The 00z European model (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.
500 mb 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.
European model (ecmwf) continues to be the outlier, as it drops an mesoscale convective system out of Minnesota and
down towards the fa Tuesday night, then bringing it across the fa
Wednesday. The European model (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 /15z Saturday through Wednesday/...
locations west of the terminals are showing LIFR/ vlifr
visibilities/cigs this morning as skies are clearing from west to
east. A low stratus deck has also formed mainly along and north of
a stationary boundary that is currently hanging around near kday
and kcmh. As the sun rises am again expecting cigs and
visibilities to rise and become VFR by mid morning. This afternoon
NAM and GFS forecast soundings are again destabilizing as daytime
heating and plenty of moisture will allow for showers and
thunderstorms to develop. Upper level lift from an upper level low
will also help to further promote development this afternoon with
slightly better lift across the east. Still though, high res
models are again showing pretty good coverage. Given the moist
atmosphere, upper level lift, and instability this makes sense.
Have gone ahead and added tempo groups into the tafs to account
Coverage will then again slowly decrease into the evening as
daytime heating is lost. Tonight into Sunday morning light
westerly winds will diminish bringing another chance of reduced
visibilities. Drier mid to low level air will start to work into
the region Sunday morning though which could help to limit fog
potential a bit. For now have left the mention of fog out for
Sunday morning given the uncertainty.
Outlook...chance of thunderstorms Wednesday.