Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
406 PM EDT Thursday Jul 30 2015
high pressure and a dry airmass will push across the area tonight
through Friday. A weak cold front may result in a few showers and
thunderstorms Friday night. After high pressure returns for
Saturday...another front with increasing moisture is expected on
Near term /until 6 am Friday morning/...
surface high pressure centered over Missouri extends into the
Ohio Valley along a westerly flow aloft. The dry airmass and
anticyclonic subsidence associated with the high will keep mainly
clear skies over the iln area tonight. Radiational cooling in the
less humid airmass will allow low temperatures in the lower to
Short term /6 am Friday morning through Saturday night/...
expect dry weather to continue during the day on Friday when high
pressure is forecast to remain nearly stationary. A weak front
will drop southeast to the area Friday night. Models indicate a
brief period of increasing moisture...wind flow and marginal
instability along the front. Though all models are in decent
agreement with regards to position and timing of the front...the
NAM moisture and instability are most favorable for convective
development. Went with a low chance for showers and
thunderstorms...ending by Saturday morning. Dry weather is
expected to accompany the return of high pressure on Saturday.
Forecast highs in the lower to middle 80s will be near to
slightly below normal.
Long term /Sunday through Wednesday/...
high pressure will start out the long term period Sunday morning
however a disturbance will bring a chance for showers and
thunderstorms to the area Sunday afternoon into Sunday night.
A frontal boundary will approach the area Monday night and remain
near the area through Tuesday night. There are some model
differences on the location of this feature and the length of time
that precipitation will remain across the area.
Models yesterday were indicating a dry day on Wednesday. GFS is
still indicating this while the European model (ecmwf) is now trying to bring a large
surge of moisture to the area. At this time kept the dry solution
and went with the GFS for this time. Continued the dry conditions
into Thursday as well.
Aviation /19z Thursday through Tuesday/...
despite the drier airmass overhead...starting to see some cumulus
popping up across the region on visible satellite but do not expect
more than scattered coverage this afternoon. Winds may occasionally
gust into the teens this afternoon as high pressure noses in from
the west. Winds and any cumulus will quickly diminish this evening
once diurnal heating ceases.
Not a great potential for br development tonight owing to dry low
levels...but the synoptic setup is somewhat favorable. There may
be just enough low level moisture to allow for some patchy MVFR
br at a few terminals towards sunrise with high pressure
overhead...clear skies and light winds. VFR conditions on Friday
with increased instability allowing for more cumulus in the afternoon
ahead of an approaching front.
Outlook...no significant weather is expected at this time.