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Area forecast discussion 
National Weather Service Jackson Kentucky
353 am EDT Wednesday Jul 30 2014

Short term...(today through thursday)
issued at 345 am EDT Wednesday Jul 30 2014

The latest surface map features high pressure oriented from the
northern plains down across the Mississippi Valley. Unseasonably cool
air is entrenched across the Ohio and Tennessee valleys...with
the deeper valleys of eastern Kentucky currently reporting in the low
50s. Aloft...cyclonic flow continues across the northeastern Continental U.S....
stemming from a deep upper level low rotating near Hudson Bay.

A short wave trough currently moving south along the western Great
Lakes will move through the Ohio Valley today...allowing for a threat
of a few showers across northeastern Kentucky. Will maintain some
isolated probability of precipitation as we heat up more at the surface today...while cooler
middle-level temperatures remain in place. Highs will top out in the middle
to upper 70s for most locations.

Another cool night is expected tonight...with the deeper valleys
likely dropping down into the low 50s once again. Ridges will be a
bit milder...winding up in the upper 50s to around 60.

Thursday will feature milder temperatures...with highs topping out in
the low 80s. A passing short wave trough along the Tennessee Valley
will threaten far southeastern Kentucky with some isolated
convection...however most of this looks to stay on the Tennessee
side...and will stick with dry weather for now.

Long term...(thursday night through tuesday)
issued at 345 am EDT Wednesday Jul 30 2014

Little has changed from previous forecast. Amplified troughing
pattern will continue to be blocked across the eastern Continental U.S....with
strong ridging sitting over the SW Continental U.S. And off the Atlantic
Seaboard. By Friday...eastern Kentucky will find itself on the leeward side
of the trough...putting much of the appalachian region in SW flow in
the middle and upper levels. Though temperatures will remain below
normal...this flow of warmer air from the south will pull temperatures back
up slightly from previous days...into the upper 70s and low 80s
through the weekend. It will also cause a slight increase in the
humidity levels as well.

As for the precipitation concerns...the blocking pattern will keep a cold
front nearly stationary along the Gulf and eastern Seaboard. addition to the moisture advection from the deep SW-to-NE
flow...will make this region prime for ongoing showers and
thunderstorms through early next week. Expect these showers and
thunderstorms to be predominately diurnally driven...with isolated
to scattered convection pulling into Kentucky to some extent each
day...mainly in the afternoon and evening. Used the latest nam12 and
gfs40 soundings to determine the likelihood of thunder each
is reflected in the weather forecast.

Then by the beginning of next week...the strong upper level ridge
off the New England coast will begin sinking southward. This will
work to increase heights across the eastern Continental U.S. a
result...dampen the amount of instability across the region.
Although a few diurnally driven showers are possible Monday along
the Tennessee and Virginia border...coverage will be quite isolated. Precipitation
chances should then fade all together from the forecast by Monday
night. On the flip side...increasing heights also will directly
correlate to increasing temperatures. Expect more seasonable middle to upper
80s by Tuesday for highs.


Aviation...(for the 06z tafs through 06z Wednesday night)
issued at 218 am EDT Wednesday Jul 30 2014

VFR conditions will gradually give way to some MVFR fog...although
expect that any IFR or worse fog to be constricted to the deeper
river valleys. The fog will burn off by around 13z...with scattered
stratocu in the 4 to 6k feet above ground level range developing during the day.
Any isolated shower activity looks to stay north of the taf sites.
Winds will be out of the west and northwest through the
period...generally around 5 kts or less.


Jkl watches/warnings/advisories...



Short term...geogerian
long term...jmw

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