Area Forecast Discussion
Issued by NWS Wilmington, OH-- Highlight Changed Discussion --
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FXUS61 KILN 180556
Area Forecast Discussion
National Weather Service Wilmington OH
156 AM EDT Tue Apr 18 2017
High pressure will build into the Great Lakes, offering dry
weather tonight into Tuesday. A chance of precipitation will
return Tuesday Night into Wednesday as moisture returns ahead of
an approaching cold front. Shower and thunderstorm chances will
increase Thursday with the passage of a cold front.
.NEAR TERM /UNTIL 6 AM THIS MORNING/...
Enhanced cirrus has been slow to progress to the southeast. In
fact, based on 00Z KILN sounding, the models are currently faster
with the 400 mb/300 mb moisture than what is currently depicted
on IR satellite. As a result, have slowed down the clearing, but
still am expecting cirrus to shift southeast and thin some
toward sunrise Tuesday. In the dry airmass, lows will be cooler
tonight, ranging from the lower/mid 40s northeast to the lower
50s along and south of the Ohio River.
.SHORT TERM /6 AM THIS MORNING THROUGH 6 PM WEDNESDAY/...
Surface high pressure will slide east across the Great Lakes
into New England Tuesday. Low level flow will veer to the south
with an increase in clouds late in the day. Under the influence
of WAA temperatures will warm to highs in the lower and middle
70s on Tuesday.
Weak s/w moving through the westerly flow will result in an axis
of 925 mb convergence. In response to this moisture and weak
forcing have a mention of showers over the south/southeast
counties Tuesday night. Lows will be milder Tuesday night due
to the increase in clouds and WAA. Expect lows in the mid and
.LONG TERM /WEDNESDAY NIGHT THROUGH MONDAY/...
The patterns in the long term are not patterns in which the
superblend does well, so quite often where there was model agreement
took them as targets of opportunity and went away from the
The forecast area will be in between two systems, one to the north
and one to the south, on Wednesday. There is some question on how
much phasing between the two systems will be present, however does
not seem like there will be much. Due to his have limited
precipitation chances to the chance category. There is some
instability so have thunder mention in as well. Southerly flow on
Wednesday will allow for widespread temperatures in the 70s.
On Thursday continued southerly flow will allow for temperatures to
climb into the 70s to low 80s. Model soundings are indicating wind
gusts 30 to 35 mph likely with some higher gusts possible. A cold
front will approach and move through on Thursday. There is decent
instability during the day. Dewpoints are sufficient in the lower
60s. The timing will be favorable although forcing could be better.
Looking at the CIPS Analog guidance there is a very good signal for
severe weather being possible on Thursday. Due to model agreement
and sufficient severe parameters in place, increased precipitation
chances and added severe threat to the HWO for Thursday. Just
mentioned damaging winds and hail, however cannot rule out tornadoes
as well and isolated flooding issues.
Precipitation will taper off Thursday night and dry conditions will
be in place for Friday. With cool northerly flow and cold air
advection on Friday decreased temperatures from superblend.
An upper level low approaches for the weekend and into the beginning
of next week. This will allow for cool and cloudy conditions along
with scattered showers. The ECMWF is the outlier and brings
precipitation in a lot quicker. Went with the slower solutions and
bring only a chance of precipitation for the day on Saturday and
more likely precipitation Saturday evening into Sunday. Isolated
thunderstorms will be possible on Sunday, but due to the isolated
nature left out of the forecast at this time. Precipitation will
gradually taper off Sunday night into Monday. Went cooler than
superblend on temperatures through this time.
.AVIATION /06Z TUESDAY THROUGH SATURDAY/...
-- Changed Discussion --Stubborn cirrus shield that has been affecting the tafs is
finally starting to shift to the south. The nrn edge has dropped
south of I-70 and it should reach the Ohio River by 12Z, leaving
the tafs mostly clear. After 12Z, the high pressure over the
Great Lakes will move east. The low level flow will veer to the
se in response.
Mid level cigs will spread north into the srn tafs around 21Z
ahead of H5 vort in the srn stream. This disturbance will work
into ern KY by 00Z and some scattered SHRA will approach
CVG/LUK. Added a VCSH to cover the possibility.
For the CVG 30 hour tafs, models are indicating that cigs will
lower to MVFR.
OUTLOOK...MVFR/IFR ceilings possible late tonight into
Wednesday. Thunderstorms possible Thursday. MVFR ceilings and
visibilities possible Saturday.
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