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Area forecast discussion 
National Weather Service Jackson Kentucky
339 am EDT Wednesday Sep 3 2014

Short term...(today through thursday)
issued at 339 am EDT Wednesday Sep 3 2014

The cold front which moved into the Ohio Valley and set off
thunderstorms on Tuesday is becoming ill defined. A moist surface air
mass remained in place over the jkl forecast area...with drier air
near our northern border. As residual clouds from precipitation slowly dry
up...fog and low clouds were trying to develop...and this should be
the case through sunrise. During the day...fog and low clouds will
slowly dissipate...and models show the drier air making a slight
southward advance into the northern part of the forecast area. This
should keep the northern part of the forecast area dry today.
Meanwhile...areas to the south exhibit forecast soundings with
sufficient destabilization for more showers. Weak lapse rates from
600-750mb may limit thunder potential...but not rule it out. Any
precipitation will die out this evening with loss of heating. Low level flow
will carry moisture back north on Thursday...and allow a potential
of convective precipitation anywhere except perhaps the northern tip of the
forecast area. Middle level lapse rates do not look quite as
formidable on Thursday...so thunder could be more prevalent than
today. The westerlies aloft will be retreating northward through the
period...so with features aloft becoming amorphous...little
organization of convection is anticipated.

Long term...(thursday night through tuesday)
issued at 339 am EDT Wednesday Sep 3 2014

A pattern change is coming...but not before one more potentially
heavy rain event. The start of the period will feature high pressure
firmly in control across the eastern US. This will yield another
mild night Thursday night and warm day on Friday. Enough moisture
will linger along The Spine of the Appalachians to yield a few
showers or thunderstorms during the afternoon. However...its looking
less widespread than it did yesterday and will feature more hit and
miss activity. However...a strong middle level shortwave will push a
sharp cold front southward into the Ohio River valley late Friday
night and Saturday. This will yield a period of very unsettled
weather as we will have forcing aloft supporting widespread showers
and storms. Much like the past few precipitation events...precipitable water values
again climb to around 1.9 during the day Saturday. This suggest the
potential for locally heavy rain again. With the forward progress of
the front slowing down over time...potential may exist for a few
training thunderstorms...leading to a flash flood threat.
Fortunately...this time around...shear is much weaker and really no
threat of severe weather.

The front will slowly inch southward Saturday night into Sunday with
a few showers possibly lingering across the south into Sunday
morning. However...by Sunday afternoon...front should be far enough
south to go with a dry forecast. Much cooler and drier air will
filter south in the wake of this front. This will bring a more
fall-like air mass into eastern Kentucky. Overnight lows are expected
to take a step back into the 50s with highs only in the 70s on
Sunday. High pressure will remain firmly in control through the
remainder of the period. Some moisture may creep back into the
southeast on Monday...but should be nothing more than a few
afternoon showers. Same could be said about Tuesday and
Wednesday...but flow turns more southerly...and downsloping flow may
keep showers more at Bay...so have left any showers out of these
periods.

&&

Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 151 am EDT Wednesday Sep 3 2014

Conditions varied widely at taf issuance from vlifr to VFR. As
middle/high clouds decrease during the night...will expect fog and low
clouds to become more extensive...with most places settling to IFR or
worse by dawn. Slow improvement is forecast during the day on
Wednesday...with VFR finally returning during the afternoon.
Scattered showers should also develop in the afternoon...mainly near
and south of a line from Somerset to Pikeville.

&&

Jkl watches/warnings/advisories...
none.
&&

$$

Short term...hal
long term...kas
aviation...hal

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