Area Forecast Discussion
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FXUS61 KILN 291928
Area Forecast Discussion
National Weather Service Wilmington OH
328 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/...
Pesky stratus deck near and south of the Ohio River is expected
to mix out by late afternoon or early evening. Otherwise,
as high pressure moves to the east overnight, a warm front will
approach the region from the southwest. Clouds will increase
from the mid and high levels, then the lower levels late. There
could be enough moist ascent for a few showers to develop ahead
of the warm frontal boundary. 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 H5 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 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 TN 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 /19Z WEDNESDAY THROUGH MONDAY/...
Stratus near and south of the Ohio River this afternoon will
continue to lift and eventually mix out through 00Z. Some
lingering MVFR ceilings will continue at KCVG/KLUK/KILN until
full mixing is complete.
For tonight, a warm front will move northeast toward our region.
We should see an increase in mid and high level clouds at first.
Then as warm, moist advection continues, clouds may lower into
MVFR late. Some showers will also be possible ahead of the
front, but coverage appears low at this time to not mention yet
as a VCSH.
For Thursday, a vigorous upper level low will rotate northeast
from the southern Plains to the middle Mississippi River Valley.
As this occurs, warm front will continue to move from south to
north through the forecast area. Again, a few showers will be
possible as this occurs. By afternoon, it is unclear per high
resolution models how much shower/thunderstorm activity will
encroach our west given weakening trend as the precipitation
propagates from its original source region. So, have kept 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.