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fxus61 Kiln 292349 

Area forecast discussion
National Weather Service Wilmington Ohio
749 PM EDT Wed Mar 29 2017

a warm front will push north across the region tonight into
Thursday. Low pressure and its associated cold front will then
move into the Great Lakes and Ohio Valley Thursday night. The
low will move off slowly to the east on Friday, with high
pressure following behind for the weekend. Warm temperatures on
Thursday will give way to cooler readings over the weekend.


Near term /until 6 am Thursday morning/...
lower stratus has mixed out of the southeastern County Warning Area this
afternoon and a thin cirrus will continue to overspread the Ohio
Valley this evening. Over northwestern portions of the cwa,
this may primarily be a more altostratus deck around 10kft which
will help insulate the region and limit nighttime dropoffs.

A warm front will approach the region from the southwest
tonight. Previous forecast had the thought that there could be
enough moist ascent for a few showers to develop ahead of the
warm frontal boundary. Models were stingy on the precip chances
tonight and early tomorrow and I dropped the chances by a bit
but did not entirely remove them. Overnight lows will range
from the lower 40s north to the lower 50s south.


Short term /6 am Thursday morning through Thursday night/...
vigorous upper level low will rotate northeast from the Southern
Plains to the middle Mississippi Valley on Thursday. The warm
front is forecast to push through the remainder of the northern
zones during the morning/early afternoon. Again, there could be
a few showers with this front. For the afternoon hours, much of
the area will be warm sector. Given an increased pressure
gradient and diurnal mixing, south winds may be gusty in the 25
mph to 35 mph range. It should be warm with highs ranging from
the mid 60s northwest to the mid/upper 70s southeast where
clouds may have some breaks. It is unclear based on various
convection allowing models whether some weakening showers/storms
over Indiana will hold together an affect western zones during
the afternoon hours. Thus, only chance pops have been employed
region wide. The threat of severe weather appears low with this
possible batch for the afternoon.

The threat for severe storms will ramp up for the first part of
of Thursday night, especially west, as low pressure and a cold
front move into the Great Lakes and Ohio Valley. As is typically
the case, appears that showers and thunderstorms will get going
to our west during the afternoon hours, generally in the
vicinity of a prefrontal convergent trough. Various convection
allowing models push a congealed, likely weakening qlcs moving
into our western zones around 03z, or 11 PM EDT, then push it
east through the forecast area overnight. Although the low
level jet will increase during the evening/overnight,
instability wanes and becomes weaker, especially east. So, if
severe weather were to occur, the primary threat would be
damaging winds. Am not thrilled about the potential for large
hail given decreasing instability. Isolated tornadoes can not be
ruled out given unidirectional speed shear, but if they did
occur, they would be of the "spin up" transient short-lived
type and not supercellular. Lows will fall into the lower to mid


Long term /Friday through Wednesday/...
period should begin with line of convection exiting the eastern
portions of the fa. An 500 mb low will then swing up the Ohio Valley in
its wake. This should add enuf lift for some scattered showers and
maybe a rumble of thunder for Friday. Highs on Friday will be held
down in the upper 50s to lower 60s by the clouds and pcpn.

The upper low will slowly exit to the east Friday night, and high
pressure at the surface will build in for Saturday. Highs on
Saturday will be near seasonable values, in the 50s.

Models begin to show their differences by late Sunday as another
system ejects out of Texas. The European model (ecmwf) is slower in the return pcpn
versus the GFS/cmcnh. Ran a compromise on the forecast with a lean
towards the wetter models. Highs Sunday will range from the mid 50s
in the north to the mid 60s in the south.

The system kicks out through the Tennessee Valley early next week. The
better pcpn is forecast south of the region, but the fa should still
see some pcpn. Highs will be 60s each day.


Aviation /00z Thursday through Monday/...
cirro and altostratus clouds will be on the increase overnight
as warm and moist air trails a warm front that will lift
northeast through the region overnight. Some of the clouds will
form a lower deck around 5-7kft late overnight and into much of
tomorrow. There may be enough mixing over the western and
southern taf sites that this lower deck could erode with mixing.
Expect slightly less mixing in central Ohio so cmh and lck will
likely keep a bkn-ovc deck through much of the day.

Cannot rule out a VFR sprinkle in central Ohio early this
morning as the warm front lifts through the area. Kept the
thinking of not entertaining vcsh due to the expected scarcity
of shower coverage.

A vigorous upper level low will rotate northeast from the
Southern Plains to the middle Mississippi River valley tomorrow.
By afternoon, it remains unclear how much shower or thunderstorm
activity will encroach western taf sites given a continued weakening
trend as the precipitation propagates from its original source
region. Continue to keep the tafs dry at this time. Winds will
become gusty from the south given a tightening pressure gradient
and some momentum Transfer of stronger winds aloft. Gusts
should be in the 25 knot to 30 knot range during peak heating.

A better chance of showers and thunderstorms is expected
Thursday night as showers/storms develop ahead of a cold front,
pushing east through the area overnight.

Outlook...MVFR ceilings and visibilities likely late Thursday
into Friday evening. Thunderstorms likely Thursday night. MVFR
to IFR ceilings likely Friday night into Saturday.


Iln watches/warnings/advisories...



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