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Area forecast discussion 
National Weather Service Jackson Kentucky
345 PM EDT Tuesday Sep 2 2014

Short term...(this evening through Wednesday night)
issued at 343 PM EDT Tuesday Sep 2 2014

A line of thunderstorms with heavy rains has formed along an old
outflow boundary across the middle section of eastern Kentucky. Some of
the storms have become near severe and expect some severe storm
warnings to be issued during the next few hours. The main threat
will be wind gusts. Another concern is that with unidirectional flow
and high precipitable water...flooding concerns will be a real issue
this afternoon and evening...mainly in the southern half of eastern
Kentucky and especially along the old outflow boundary. Expect the
front to push the precipitation south of the area by Wednesday
morning. In general...the hrrr and rap have not been doing too well
with this system so far. Wednesday figures to be a little more
comfortable as the humidity will be a little lower.

Long term...(thursday through tuesday)
issued at 301 PM EDT Tuesday Sep 2 2014

The models begin the extended period in pretty good agreement once
again...with a ridge of high pressure...both aloft and at the
surface...centered over the eastern Gulf of Mexico...along with a
well defined trough of low pressure aloft taking shape over the
northern plains. The models have the ridge steadily breaking down
to begin the period...with showers and storms popping up beneath it
across the Tennessee Valley down to the Gulf and across portions of
the southeastern Continental U.S.. as the trough evolves and
will eject out of the plains Wednesday and Thursday...and push
across the Great Lakes and Ohio Valley regions. The cold front
trailing from this upper low will end up being our weather maker for
the upcoming weekend. The front is expected to interact with
moisture coming off the Gulf of Mexico on southwesterly winds. The
front will have a difficult time moving the
ridge digs in a bit just off the southeast coast and flow aloft
becomes more zonal. There will be a good chance of rain Friday
morning through Sunday lift and moisture along the
sluggish front set off repeated rounds of showers and storms. The
rain should finally move out of the area Sunday the
front finally moves out of the area.

Temperatures to begin the period look to be above normal...with
highs topping out around in the middle to upper 80s Thursday and
Friday. Once the front stalls across the area and precipitation
becomes more widespread...temperatures will likely maximum out below
normal values Saturday through Monday. The positioning of the front
over the weekend will allow for some cooler and drier air to filter
into the area. Highs on Saturday should be just below
the bulk of cool air should still be trapped north of the Ohio
River. On Sunday...however...once winds have shifted to the
north...temperatures will be quite cool...with readings peaking in
the middle to upper 70s for most locations. The northerly flow will
only allow for a small warm up on highs that day will
likely only top out in the upper 70s and lower 80s.


Aviation...(for the 18z tafs through 18z Wednesday afternoon)
issued at 156 PM EDT Tuesday Sep 2 2014

Eastern Kentucky is primed for thunderstorms as moist and unstable
conditions are prevalent across the area. There is an old outflow
boundary bisecting the area which we are watching as a Focal Point
for convective initiation and there is also a front which is moving
toward the area from the northwest with lots of prefrontal convection
out ahead of it. Mainly VFR conditions are expected at the taf sites
this afternoon and evening except for in the vicinity of the
thunderstorms and rain showers. Put some tempo conditions in the taf
as the best estimate as to when thunderstorms are most likely affect
them. Expect some vlifr to form at the taf stations as well as the
valleys later this evening as the convection moves off to the south
and east.


Jkl watches/warnings/advisories...


Short term...jj
long term...Arkansas

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