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-- Discussion containing changed information from previous version are highlighted. --
892
FXUS61 KRLX 271946
AFDRLX

Area Forecast Discussion
National Weather Service Charleston WV
346 PM EDT TUE SEP 27 2016

.SYNOPSIS...
A large upper level low drops into the area Wednesday and
Wednesday night, and then swirls about the area Thursday through
Saturday, before pulling away Sunday.

&&

.NEAR TERM /THROUGH WEDNESDAY/...
As of 1121 AM Tuesday...

A broad and strong upper to mid level low pressure system will
move south over the OH Valley and WV tonight into Wednesday night
and Thursday. This low will bring some forcing, but with dry
atmosphere, showers or storms will stay in the light side. The low
will rotate overhead through the end of the week.

A new air mass is in place with dewpoints in the mid 40s, slowly
increasing into the 50s late Wednesday. Patchy river valley fog
will likely develop over the preferred sites, EKN and CRW
overnight.

Used the super blend and all blend for temperature through the
period.

&&

.SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/...
-- Changed Discussion --
As of 330 PM Tuesday...

As has been advertised over the past few days...our weather will
be dictated by an anomalous deep upper low dropping south from
the Great Lakes. This upper low gradually becomes cutoff by Friday
over KY. Rounds of shra and even tsra can be expected thru the
period...enhanced by diurnally driven instability amid steep low
level lapse rates. Timing these spokes of energy is challenging
but enough model agreement for some detail in the POP grids
exists. It appears greatest chances for precip will be across the
northern half of the CWA and concentrated in the Thursday and
Friday time frame. All in all a much welcomed pattern that should
give many some beneficial rain.

Temps thru the period will run several degrees below average for
day time highs...which is quite the reversal over the last several
weeks. In fact...some areas in NE KY and W WV may struggle to
reach the 60 degree mark Thursday and Friday given the proximity
to the significant cold pool and expected shra.
-- End Changed Discussion --

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
-- Changed Discussion --
As of 330 PM Tuesday...

The pesky upper low will gradually track north over the
weekend...with less of an influence on the sensible weather as the
days progress. This will result in a dry pattern taking hold again
with temperatures moderating to normal and eventually above
normal.
-- End Changed Discussion --

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
As of 130 PM Tuesday...

Satellite and radar image show clear skies across the entire area.
A deep low pressure system over the Great Lakes region, will move
south over the OH Valley and WV tonight. Expect mostly clear skies
tonight. With radiational cooling, IFR/LIFR river valley fog will
develop most likely at EKN, CRW, and HTS. Any dense fog should
dissipate by 13-14Z.

Widespread VFR conditions expected Wednesday. However, vorticity
maxes around the low`s center could bring some forcing and chances
for showers or storms Wednesday night into Thursday.


FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY...

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Development and extent of any fog overnight
may vary from forecast.

EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO FORECAST TO AVAILABLE MODEL INFORMATION:
H = HIGH:   TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.
M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS.
L = LOW:    TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL.

UTC 1HRLY       18   19   20   21   22   23   00   01   02   03   04   05
EDT 1HRLY       14   15   16   17   18   19   20   21   22   23   00   01
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
EKN CONSISTENCY  H    H    H    H    H    H    H    H    H    M    M    L
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M

AFTER 18Z WEDNESDAY...
Morning valley fog possible through Friday morning.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...None.
OH...None.
KY...None.
VA...None.

&&

$$
SYNOPSIS...ARJ/30
NEAR TERM...ARJ
SHORT TERM...30
LONG TERM...MPK/30
AVIATION...ARJ