Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
829 am EDT Friday may 29 2015
showers and thunderstorms will be possible today in a warm and
humid southerly flow. Moisture associated with a slow moving cold
front will provide a few more rounds of showers and thunderstorms
Saturday through Monday. High pressure and drier air can be
expected by the middle of next week.
Near term /until 6 PM this evening/...
compact vorticity center lifting north along the I-75 corridor
will move out of the forecast area this morning taking associated
showers with it. With heating scattered showers and thunderstorms
will redevelop this afternoon. Weak forcing makes it difficult to
determine whether any one location has a better chance of seeing
storms relative to another. Weak shear and modest instability
should mean that this activity will just bring local downpours.
Short term /6 PM this evening through Sunday/...
a relative lull in convection should occur tonight with loss
daytime heating in a environment of weak forcing. For
Saturday...a cold front will be approaching from the northwest.
The slow moving front will feature a plume of copious moisture
streaming from the southwest...with precipitable water about 180 percent of
normal. Increasing convergence coupled with cooler air aloft will
provide a prolonged period during which convection will be likely.
The most favorable time for widespread organized convection will
be Saturday evening when frontal position and lingering
instability will coincide. The gradual movement of the front will
allow showers and thunderstorms to persist on Sunday. The threat
for severe thunderstorms appears marginal at this time due to
limited instability and wind shear. Localized flooding will be
possible due to the moist airmass and the slow moving nature of
High temperatures should stay in the lower 80s Saturday in the
persistently warm southerly flow ahead of the front. Cooler highs
averaging around 70 are expected Sunday in clouds...precipitation and
Long term /Sunday night through Thursday/...
a large area of high pressure will situate itself over the Great
Lakes region and Northern Ohio valley Monday. As the winds shift
around the departing high...east winds will prevail over the
region as an inverted surface trough may be a focus for shower
activity over Kentucky.
HPC showing a warm front lifting NE through the region on Tuesday
which is not apparent in the surface depictions for either Tuesday
or Wednesday next week. Southerly flow begins to take a more
pronounced hold on the region Wednesday which may help support the
argument for a warm front north of the Ohio Valley Wednesday and Thursday.
Temperatures will be cool to start with. Sundays highs middle 60s north to middle
70s south...warming to the lower and middle 80s by Thursday and
Friday. Overnight lows in the 50s Sunday night will nose to the
lower 60s Tuesday night. By then there should be increased moisture
to the region so that middle and upper 60s are more indicative of
overnight lows for the latter part of next week.
Precipitation will be pushed to the south Sunday and never quite leave the
forecast entirely as the northern push of colder and drier air may
be a strong enough convergent force over Kentucky where some more moist
air will reside. Initially thought thunder for the forecast but
toned back to just showers beginning Sunday night and lasting
through early Wednesday...coinciding with the lower chances of
precipitation. After this time daytime heating and a return to south flow
would necessitate inclusion of thunder to the forecast.
Aviation /12z Friday through Tuesday/...
high clouds spilling in from the west. Daytime heating should
bring scattered rain showers and thunderstorms and rain with best timing indicated in taf
forecast. Convection should diminish with sunset. Some light fog
developing late tonight with lighter winds and moist air. Winds
will pick up during the day today with some gusts around 20 knots.
Outlook...thunderstorms will be possible Saturday afternoon into
Sunday. MVFR ceilings possible Saturday night through Monday