Area forecast discussion
National Weather Service Wilmington Ohio
725 PM EDT Tuesday may 21 2013
Synopsis...
with an unstable airmass in place showers and thunderstorms will
be possible across the region this evening. Thunderstorms will be
present across the area on Wednesday in advance of a cold front.
The cold front will move through the area late Wednesday night
into Thursday.
&&
Near term /until 6 am Wednesday morning/...
isolated showers and thunderstorms have developed across the southeast
half of the forecast area. Surface analysis shows that this is in an area of
higher dewpoints. Dewpoints across the southeast are in the middle to
upper 60s while across northwest portions of the forecast area dewpoints are down to
the low to middle 50s. Although cannot completely rule out severe
activity across northwest portions of the forecast area...believe that the best
chance of seeing isolated severe storms this evening will be southeast of
a line from kcvg to kcmh. There is better instability across this
area. Dcape values are also decent across this area and expect the
main threat from the storms to be damaging winds. Some hail will
also be possible however not expecting a lot of large hail. Expect
the severe threat to diminish around sunset. Some of the models
are indicating a few storms may develop and move into extreme northwest
portions of the later this evening into early tonight however
believe the threat is minimal due to drier air in place.
Additional thunderstorm activity will begin to move into western
portions of the forecast area late during the overnight hours and into the
early daytime hours on Wednesday. Went close to guidance for low
temperatures overnight.
&&
Short term /6 am Wednesday morning through Wednesday night/...
showers and thunderstorms will continue to overspread the forecast area
during the daytime hours on Wednesday. There is still some
question as to the severe potential for Wednesday. There is better
instability across eastern portions of the forecast area for Wednesday. In
addition storms will hold off a little longer across eastern
portions of the forecast area which will allow for some more heating. Due to
this believe that the better severe threat will be across eastern
portions of the forecast area for Wednesday with the main threats being
damaging winds and large hail. Precipitation coverage across the area
will diminish during the late evening hours however some isolated
activity will still remain possible. Additional showers and
thunderstorms will begin to move into western portions of the forecast area
late in the overnight hours Wednesday night as the cold front
approaches the area.
&&
Long term /Thursday through Tuesday/...
showers are likely to develop mainly over northern locations on
Thursday as a sharp upper trough and cool airmass push through the
Great Lakes and Ohio Valley. Friday will be dry and cool with high
pressure crossing the area. Dry weather should continue on Saturday
for most of the area except for far southeast counties where a
developing frontal boundary may cause a few showers.
For Sunday through Tuesday...that frontal boundary is forecast to
linger across Kentucky. This pattern will provide a chance of
showers each day to the southern part of the forecast area...with
northern locations enjoying a period of dry weather.
Slightly below normal highs averaging in the lower 70s on Thursday
will be followed by below normal 60s on Friday under clouds and
showers. Temperatures will then gradually rebound from Saturday
Onward...with highs reaching the middle and upper 70s by Tuesday.
&&
Aviation /23z Tuesday through Sunday/...
possibility of thunderstorms will continue to be the main concern
through the taf forecast period. Northern fringe of linear convective
system pushing through southeast Ohio will stay southeast of the taf sites this
evening. Short term trends continue to suggest that the possibility
of convection for this evening is decreasing. Therefore...start
the tafs off dry through the evening hours.
Next complex developing over the lower MS valley will track NE into the
Ohio Valley overnight. Mesoscale models indicating that convection
in a weakening phase pushes into western Ohio between 06z and
12z. There is a good deal of uncertainty regarding what will be
left. At this time...have increased clouds and added a mention of
vcsh to all tafs.
Southwest gusty winds will pick up again on Wednesday. Have gusts
as highs as 26 kts. There is a chance of showers and thunderstorms
any time after 12z...but the higher probability will be very late
in the taf period. Have mentioned thunderstorms in the vicinity during the afternoon and then
late in the taf period have prevailing showers and thunderstorms in the vicinity during this
higher threat period.
Outlook...thunderstorms likely Wednesday evening. MVFR to IFR
ceilings possible late Wednesday night into Thursday morning. MVFR
ceilings possible again Thursday night.
&&
Iln watches/warnings/advisories...
Ohio...none.
Kentucky...none.
In...none.
&&
$$
Synopsis...Novak
near term...Novak
short term...Novak
long term...coniglio
aviation...Arkansas
