Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
420 am EDT Wednesday Aug 27 2014
a weak cold front will drop south across the area today...bringing
a chance of thunderstorms. High pressure will then build over the
Great Lakes and Ohio Valley...providing warm and mainly dry weather
Thursday and Friday. Another cold front is forecast to move in
during the weekend...causing an increased risk for thunderstorms
Near term /until 6 PM this evening/...
cold front extends across Lake Erie through Northwest Ohio to
central Indiana and southern Illinois. A small cluster of
thunderstorms has developed along the front between FWA and okk.
The slow moving cluster could reach west central Ohio early this
morning so increased probability of precipitation there through middle morning.
As the front sags southward later this morning and this
afternoon...additional thunderstorm development will be possible.
Models indicate southwest counties could see the most coverage
later this afternoon...as short wave energy and moisture transport
come into phase...leading to increased instability and triggering
High temperatures are forecast to range from the middle 80s north to
around 90 south. Heat indices reaching the middle and upper 90s along
and south of the Ohio River will warrant mention in the severe weather potential statement.
Short term /6 PM this evening through Friday/...
scattered thunderstorms will die down early tonight as the front
drops south and daytime heating wanes. Surface high pressure will
follow the front. As the high center moves slowly from the eastern
Great Lakes to the middle Atlantic coast Thursday and Friday...model
trends indicate that mainly dry weather will result from
subsidence associated with the high. The exception may be in far
western counties...where return flow circulating around the high
could bring increasing moisture and isolated thunderstorms Friday
Warm conditions will persist. Highs on Thursday are forecast to be
in the low to middle 80s...then rising as high as the low 90s on
Long term /Friday night through Tuesday/...
have taken a blend of the European model (ecmwf)...CMC...and GFS for Saturday.
Thereafter...have sided with a slightly faster solution for main
middle level trough for the latter half of the weekend per a GFS/CMC
For Saturday into Sunday...middle level trough and embedded shortwave energy
will shear some as they head northeast into the Great Lakes. A cold
front will also push slowly southeast toward the region from the
northwest. Increasing moisture with generally weak to moderate forcing
will bring an increasing chance of showers and storms Saturday night
For Sunday night into Monday...aforementioned energy continues to
pivot and shear as it moves northeast toward New England.
Meanwhile...frontal boundary stalls just to our northwest as it
becomes parallel to middle level southwesterly flow. Precipitation chances will
decrease Sunday night from west to east...with a chance of mainly
diurnal showers and storms on Monday.
Elongated middle level ridge may become quasi-stationary...extending
from off the middle Atlantic coast to the Ohio Valley and points to the
south from early to middle week next wee. This will keep at least a
chance of showers/storms going with the diurnal cycle being most
Summer temperatures can be expected into the first part of the
weekend with a little bit of a cool down on Sunday due to clouds and
precipitation. Temperatures will return to the upper 80s to around 90 for the
beginning of next week as warm/moist air circulates around elongated
middle level ridge.
Aviation /07z Wednesday through Sunday/...
slow moving cold front over Northern Ohio will dip south to the
Ohio River this afternoon. In the moist airmass ahead of this front
fog will develop this morning. Most locations will observe MVFR
visibility restrictions with the exception of kluk where IFR visibilities will
Scattered shower and thunderstorm will develop in vicinity of the southward
sagging cold front. Some of the global models are developing precipitation
toward sunrise but expect more of a diurnal nature to these
storms. These storms will be more scattered in coverage. Therefore...
have limited precipitation mention to thunderstorms in the vicinity for the period when the greatest
chance of a thunderstorm is expected. Southwest winds at 5 kts or
less winds will shift to the north behind the front at 10 kts or
less today and then light northeast tonight.
Outlook...scattered thunderstorms possible on Saturday and Sunday.