Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Wilmington Ohio
336 PM EDT sun may 24 2015
high pressure that has allowed for pleasant conditions the last
couple of days has continued to pull east today allowing for
warming conditions along with rising humidity. As the ridge axis
slowly moves east into the first part of the week...moist...southwest
flow will interact with embedded disturbances aloft to bring the
threat for showers and thunderstorms.
Near term /until 6 am Monday morning/...
moisture advection will continue overnight allowing dewpoints to
continue their climb. Cloud cover also looks to hang around
Monday morning so low temperatures will be about 5 to 10 degrees above
what they were Sunday morning.
Short term /6 am Monday morning through Tuesday night/...
an upper level low currently over The Rockies will begin to become
dislodged Monday allowing for the ridge axis to push east and the
chance of rain to return to the area. A shortwave currently over
central Texas will continue to push towards the northeast with a
line of positive vorticity advection slowly moving east. This thin line of positive vorticity advection will move
over the area Monday afternoon. High res models are showing
scattered showers and thunderstorms forming along this line of positive
vorticity. Forecast soundings are showing lower end instability
with k index values in the lower to middle 30s. This all supports
chance probability of precipitation. High temperatures will be in the lower to middle 80s. It
will also be windy Monday as the pressure gradient tightens with
some of our northern zones possibly seeing sustained winds above
Behind the initial wave of positive vorticity advection there will probably be a brief
break in the rain. On Tuesday there will be another shortwave that
swings through central Texas that ejects to the northeast. This
shortwave will finally help to clean up the flow and move the
upper level low over The Rockies to the east. This will bring
another area of positive vorticity over our western zones. The jet
streak associated with the shortwave will also push to the east
putting the area into a rrq. Storm Prediction Center has the SW part of the County Warning Area in a
slight risk for severe storms Tuesday. Model forecast soundings
for Tuesday have cape values just above 500 j/kg. Instability in
the sounding still is taking on a skinny cape. The main threat
will be for wind but this threat still remains pretty low at this time.
Long term /Wednesday through Sunday/...
a fairly progressive westerly flow pattern in place across the
region for middle week will result in a chance of thunderstorms
Wednesday into Thursday. While precipitation chances will depend on the
timing of any embedded short waves...will try to show some diurnal
enhancement to the precipitation chances for both Wednesday and Thursday.
The flow will gradually become more amplified through the weekend
as short wave energy moves into the Central Plains. Initially this
will lead to a little middle level ridging across our area Thursday
night into Friday and possibly a brief lull in the precipitation chances. A
better chance of precipitation will then return later Friday and into the
weekend with the approaching trough and short wave energy. This will
eventually help push a cold front down toward our area Saturday into
Sunday. However...the models have been trending slower on the timing
of this front over the last several runs so am hesitant to go any
higher than chance category for the probability of precipitation at this point.
Highs will remain seasonably warm through at least Saturday with
highs in the lower to middle 80s and overnight lows in the middle to upper
60s. Depending on the timing of the front...some more seasonable
readings may return for Sunday.
Aviation /19z Sunday through Friday/...
VFR will continue even as moisture increases ahead of a slow
moving cold front. Dry southerly flow featuring middle and high clouds
will persist through tonight. A few showers may occur on
Monday in the vicinity of taf sites under increasing short wave
energy...while ceilings stay over 3500 feet. Wind speeds will rise
Monday in the tightening pressure gradient...with gusts close to
30 knots out of the southwest expected Monday afternoon.
Outlook...thunderstorms with MVFR ceilings/visibilities possible Monday night