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Area forecast discussion 
National Weather Service Jackson Kentucky
419 am EST Sat Feb 13 2016

Short term...(today through sunday)
issued at 419 am EST Sat Feb 13 2016

Final band of more consistent light snow/flurries currently pushing
through eastern Kentucky this morning should bring the end to any
additional dustings in term of accumulation. Additional sparse
bands...sourcing from Lake Michigan...will push through the Ohio
River valley and into the higher terrain this morning. However...
increasing subsidence on the southwestern periphery of an upper low
pushing through western Quebec should keep these bands from
producing more than flurries/very light snow showers. Brisk
northwest winds will decrease to 5-10 miles per hour this morning with gusts
becoming less frequent through the day as surface ridging approaches
the Ohio Valley. Before this...wind chills this morning will drop to
near or below zero across a good portion of the region. Continued
cold air advection ahead of this Stout ~1040 mb ridge will make
for a raw day across east Kentucky...with high temperatures only
climbing into the middle teens to low 20s.

Aforementioned surface ridge moving overhead this evening and early
tonight will lead to a calm and crisp night as temperatures fall
into the single digits to low teens. A few valleys near the Virginia
state line and in closer proximity to the cold dome of the ridge may
very well drop below zero by Sunday morning. Backing upper
flow...ahead of a shortwave trough propagating through the Midwest
toward the Ohio Valley...along with veering surface winds in wake
of the departing ridge will usher in warmer air aloft later
tonight into Sunday. This will help draw a stream of Gulf moisture
north ahead of this upper disturbance. Top-down moistening will
lead to increasing high-middle cloud cover from Sunday morning
through the day...before low clouds and another period of snow
commence Sunday afternoon. The Bluegrass region and points south
will see this move in during the early-middle afternoon timeframe
before locales off to the east begin to see snow by late
afternoon. Prior to sunset...snowfall will approach one inch from
Mount Sterling to Flemingsburg with generally a dusting to half an inch
elsewhere. Temperatures Sunday afternoon should be able to warm
into the middle 20s north to low 30s south...likely helping to keep
treated roadways manageable through the afternoon.

Long term...(sunday night through friday)
issued at 419 am EST Sat Feb 13 2016

The period will begin with a approaching upper level wave and
isentropic lift potential for Sunday night into Monday. Confidence
continues to increase that this will start...as all snow across
the region based on time heights and forecast soundings. Given the
increased confidence but still later period will go with Special Weather Statement in
coordination with surrounding offices. Think headlines are
certainly possible if trends continue with later model runs.
Overall right now looking at 2-4 inches within the period from
Sunday into early Monday. Models do suggest potential for a
deformation zone...however location uncertainties still exist and
this would have major implications of snow amounts. After this
models remain all over the place run to run...will say a good
portion of the latest model suite has trended in tracking a
surface low across the Tennessee Valley Monday afternoon. This would
appear to spell a bit more in the way of potential mixing to all
rain on Monday afternoon for most of the region...with even some
of the forecast soundings loosing ice. Right now will lean away
from the cooler 00z NAM...given it seems to be the outlier in
relations to it/S progressive nature. After this low swings NE of
the region and cold air will advect in on the backside...this will
lead to yet another change over back to snow Monday night. Right
now keeping the ratios lower here and better quantitative precipitation forecast lines along our
Virginia border. Therefore right now thinking lighter accumulations for
that period...however confidence remains quite low.

That system will exit to the NE...while another wave rides the
coat tails and is poised to bring another surface low southeast across
the region. Once again models are in a fair amount of disagreement
on timing and placement of this system...pop wise leaned toward
the model blend. Does look like enough warm air will be in place
to lead to a change over to all rain Tuesday and back to snow
Tuesday night. However timing and location will play a critical
role in precipitation types for this system. High pressure will progress
across the Ohio Valley and into the middle Atlantic by the end of the
period. This will bring return flow and coupled with rising
heights will lead to moderating temperatures. Matter of fact blends would
suggest temperatures on Friday may be able to climb into the lower 60s in
some spots.

&&

Aviation...(for the 06z tafs through 06z Saturday night)
issued at 102 am EST Sat Feb 13 2016

Northwest winds of near 10-15 knots with gusts approaching 20
knots continue tonight with strong cold air advection in place.
This is creating some light to moderate snow bands...with up to a
tenth or two possible at kjkl/ksjs early tonight before tapering
off. Occasional MVFR ceilings will gradually improve to VFR for
all sites by early morning as northwest winds decrease to 5-10
knots.

&&

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

$$

Short term...Guseman
long term...dj
aviation...Guseman

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