Area forecast discussion
National Weather Service Wilmington Ohio
632 am EDT Sat may 18 2013
Synopsis...
a frontal boundary will remain across the region through the
weekend...keeping unsettled conditions over the area. A weak upper
level ridge will build into the region on Monday as an upper level
trough deepens over the plains.
&&
Near term /through tonight/...
a quasi stationary boundary will remain across the region through
tonight. This feature will team up with a slow moving upper level
trough over the Ohio Valley. The combination of the two will keep
the threat of showers and thunderstorms going today...with the
highest chance along and south of the Ohio River. For
tonight...the loss of daytime heating and diminishing forcing will
result in a decrease chance of precipitation with only a slight chance of
showers expected across the eastern/southern zones by Sunday morning. Highs
today will range from the middle to upper 70s. Lows tonight will
generally be the lower 60s.
&&
Short term /Sunday through Monday night/...
have used a blend of the 18.00z GFS and the 18.00z European model (ecmwf) for the
short term forecast.
Upper level trough will begin to push southeast on Sunday. This will allow
shortwave ridging to build into our western zones. The lingering trough
in the east will keep the threat of showers/storms in the
forecast...but coverage should be less than today. Shortwave ridge in
the west along with a weak cap should prevent precipitation there.
For Sunday night into Monday...shortwave ridge will push across the
region as old frontal boundary lifts north as a warm front into
the Great Lakes. We should see warming temperatures with only a
small threat of showers and thunderstorms during the afternoon across the
far northwest where capping will be the weakest. Highs on Monday will be
in the middle to upper 80s.
For Monday night...shortwave ridge will push east of the area while upper
level closed low deepens over the plains. Energy rotating around the
low will begin to eject NE toward the region. This will once
again increase the threat of showers and storms...mainly across western
and northern locales.
&&
Long term /Tuesday through Friday/...
low pressure will approach the region on Tuesday with a continuing
threat of showers and thunderstorms. Thunderstorm chances will
continue in the forecast on Wednesday and into Wednesday night as
a cold front approaches the region. The cold front will move
through the region on Thursday. Cool and dry conditions will be in
place after the frontal passage with high temperatures in the 60s
for Friday.
&&
Aviation /12z Saturday through Wednesday/...
the low level air mass will not change substantially over the
next 24 hours...leading to another day of moist conditions and a
chance for generally-diurnal showers and thunderstorms.
Several areas of showers are moving through the area this
morning...with additional precipitation moving in from the south.
Though these showers will generally be light...and insignificant
to flight categories...some brief MVFR conditions are possible at
the Cincinnati taf sites. Although MVFR cloud heights are located
not far away in Kentucky and southern Indiana...VFR ceilings
should continue for all the taf sites.
Showers and thunderstorms will develop again this coming
afternoon. With weak shear and weak instability...strong storms
are not expected...and the storms should be disorganized.
However...the storms will be slow moving capable of some brief
heavy downpours. Because of that...there is some potential for
MVFR/IFR conditions this afternoon in the convective
precipitation. This activity has been forecast most notably at the
Cincinnati taf sites...with a lower amount of confidence in
kday/Kiln...and even lower confidence for Columbus.
Tonight...more clearing is expected than this past overnight
period...especially at the western taf sites. IFR visibility
conditions are being forecast for kcvg/kluk...with MVFR mist
elsewhere. The Columbus taf sites will be the most likely to get
into some larger-scale lower ceilings (perhaps MVFR
category)...but there is some concern in the possibility of
IFR/LIFR stratus development at any of the taf sites.
Outlook...thunderstorms are possible on Sunday...primarily
in the afternoon and evening. MVFR to IFR visibilities are
possible Saturday and Sunday nights. Thunderstorms will also be
possible Tuesday night through Wednesday.
&&
Iln watches/warnings/advisories...
Ohio...none.
Kentucky...none.
In...none.
&&
$$
Synopsis...Hickman
near term...Hickman
short term...Hickman
long term...Hickman/Novak
aviation...hatzos
