Area Forecast Discussion
Issued by NWS Jackson, KY

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FXUS63 KJKL 311900

Area Forecast Discussion
National Weather Service Jackson KY
300 PM EDT TUE MAY 31 2016

.SHORT TERM...(This evening through Wednesday night)
Issued at 300 PM EDT TUE MAY 31 2016

A few showers and thunderstorms have developed in the higher
terrain in VA, NC and TN this afternoon. These have remained
nearly stationary, but there is still an outside chance of a small
shower or thunderstorm developing in KY somewhere near the TN or
VA border late this afternoon. Will make any needed adjustments to
the hourly NDFD if radar and/or satellite trends indicate the need
to add a small chance near TN and VA for a few hours late this

Another quiet night weather wise is in store for the region
tonight. Fog was mainly confined to the river valleys last night,
and for tonight the forecast will follow the same idea. For
Wednesday low level flow becomes more southwesterly, with a
gradual increase in low level moisture. While convection today has
remained to our south and east, based on latest trends and model
data will introduce a small chance for showers and thunderstorms
near TN and VA for Wednesday afternoon. Chances will gradually
increase Wednesday night as a front approaches from the northwest.

Temperatures will remain summer like with lows tonight and
Wednesday night in the 60s and highs on Wednesday in the mid to
upper 80s.

.LONG TERM...(Wednesday night through Monday)
Issued at 355 AM EDT TUE MAY 31 2016

The models are in good agreement aloft with the broader scale
pattern for the extended portion of the forecast, but shorter wave
details will have a large impact on the weather specifics through
the weekend. It is these details that lead to lower than normal
confidence in the sensible wx during at least the first part of the
extended. For the longwave pattern, the models all have southeast
ridging weakening in the face of a broad trough sliding east through
Texas and into the lower Mississippi Valley for the weekend. The
northern stream contributes to the end of the southeast ridge with a
decent trough dropping into the Upper Midwest and Great Lakes on
Saturday in fairly good model agreement. This trough will settle
deeper into the Ohio Valley Sunday into Monday with the ECMWF
shallower and more progressive than the GFS, at this time. Will
favor a general blend through the bulk of the extended, but also
give a nod toward the latest 00z ECMWF solution for the SFC pattern
into the weekend when the models are most different across our area.

Sensible weather will feature moisture return and an approaching
front returning PoPs to the forecast for Thursday with the best
chances that afternoon and into the night. Any storms could be
strong on Thursday given the instability so will continue the
mention of a gusty wind threat in the HWO. Friday is where the
model frontal differences come into play with the GFS taking its
boundary south through East Kentucky by afternoon while the ECMWF
is, for at least the second run in a row, lingering its front
through the CWA, or just to the northwest into Saturday. It actually
doesn`t push its front to the south of eastern Kentucky until midday
Sunday with upper support from the trough moving into the Great
Lakes. Meanwhile, the GFS allows a wave to takes its front back into
the area on Saturday before clearing out in tandem with the ECMWF on
Sunday. So, the issue is how much of a lull will we see in
convective activity from Friday afternoon through Saturday
afternoon. Currently am playing a little break, but confidence in
that is low given the disagreement from the ECMWF. Regardless, with
the fairly high moisture content associated with the front and
potential for training cells will continue to highlight flood
concerns for Thursday into Friday in the HWO. The rest of the
forecast will feature a solid cool down Sunday into Monday when the
trough induced front brings a true change in air mass along with
drier conditions, into our area.

Adjusted the grids from the CR initialization mainly to tweak some
low temperatures for terrain distinctions on Thursday and Monday
mornings. Also, nudged the PoPs to a certain extent more toward the
latest ECMWF going more pessimistic with respect to the front
clearing the area.


.AVIATION...(For the 18Z TAFS through 18Z Wednesday afternoon)

VFR conditions will prevail through this TAF forecast period, with
only a few cumulus clouds this afternoon and again Wednesday
afternoon. Isolated showers and thunderstorms have developed over
the mountains south and east of KY, but these are expected to
remain over VA, NC and TN this afternoon. Fog was mainly confined
to the river valleys this morning, with no fog at JKL, SME or LOZ
and only brief periods of MVFR fog at SJS (less than 1 hour) and
SYM (less than 2 hours). As such have left fog out of the TAFs
for now, but still expect fog in the river valleys late tonight
and early Wednesday.


.JKL Watches/Warnings/Advisories...


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