Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
413 am EDT Sat may 30 2015
moisture associated with low pressure and a slow moving cold front
will bring increasing chances for showers and thunderstorms today
through Sunday. High pressure will bring cooler and drier air for
the beginning of the work week. Warmer temperatures will return
later next week as the high travels slowly eastward.
Near term /until 6 PM this evening/...
area is in a persistently humid southerly flow between high
pressure centered to the east and a low pressure system to the
west. Isolated showers have dissipated early this morning leaving
partly to mostly cloudy skies. Latest rap shows precipitation developing
within the next couple of hours but this appears overdone. Will
continue to monitor.
A surface low forming over Missouri at the tail end of a cold
front will move to Illinois this afternoon. Expect showers and
thunderstorms to redevelop today as instability and forcing
increases ahead of the low...especially this afternoon during peak
heating. Best chance for convective development will be in
northwest counties closer to the axis of an upper trough centered
over the Mississippi Valley. A few strong thunderstorms will be
possible this afternoon but rather weak instability and wind shear
will limit severe potential.
High temperatures will reach the lower to middle 80s.
Short term /6 PM this evening through Monday/...
there may be a temporary lull in convection this evening with loss
of daytime heating. By later tonight...surface low pressure pushed
to Ohio by the upper trough will produce a notable increase in
forcing. Showers and thunderstorms are a near certainty in
northern counties that will be on the north side of the low track. A
potent low level jet...copious moisture and a band of deformation
will all come into play to produce perhaps as much as two inches
of rain in northern locations. Rain chances will decrease toward
the south away from the most favorable forcing.
Widespread showers will diminish Sunday as the low moves east and
the low level flow becomes northwest. Thunderstorms will be less
evident on Sunday in a regime of decreasing instability. High
pressure and a dry airmass will move in Monday on a northwest
The northerly low level flow behind the low will bring cooler
temperatures. Highs on Sunday will vary from the low 60s northwest
up to the upper 70s southeast. Highs in the 60s are expected in
most locations on Monday.
Long term /Monday night through Friday/...
forecast has shifted in timing return flow to the Ohio Valley. A
slower shift of winds in the Tuesday-Thursday time frame from east to
eventually south has helped keep a drier and cooler forecast for the
better part of next week.
A large area of high pressure north of the Great Lakes region will
extend a ridge southwest into the Northern Ohio valley Tuesday through
Wednesday. The high will settle in the Ohio Valley on Wednesday
and then meander eastward overnight and Thursday.
With the northeast to east winds holding sway over the region
through this time...have removed probability of precipitation until Thursday afternoon when
some return to southerly flow and increased moisture would be
expected. Temperatures through this time will be below normal...starting
with highs in the upper 60s to low 70s Monday rising to around 80
Wednesday and low to middle 80s for the end of the week. Drier air will
permit lows to dip into the 50s Monday night and increase to around 60
Wednesday night...jumping to the middle 60s when the flow turns south and
moisture increases late in the forecast.
Aviation /07z Saturday through Wednesday/...
can/T rule out a stray shower developing prior to sunrise...but
chance is too low to mention in tafs. In moist flow...expect
potential for MVFR visible in br at kluk...otherwise VFR this morning.
Scattered showers and thunderstorms are expected this
afternoon/early evening...continued thunderstorms in the vicinity in tafs. It looks like
most of the middle to late evening shower/thunderstorm activity will
reside just northwest of the terminals closer to a front/low
pressure...but chances may start to increase again toward the
day/cvg terminals close to 06z.
Outlook...showers and thunderstorms are possible Sunday.
Potential exists for MVFR or IFR ceilings late Sunday through Monday