Area Forecast Discussion
Issued by NWS Charleston, WV

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147
FXUS61 KRLX 032101
AFDRLX

Area Forecast Discussion
National Weather Service Charleston WV
401 PM EST Sat Dec 3 2016

.SYNOPSIS...
Weak upper trough Sunday into Sunday night. Low pressure Monday
night Tuesday. Briefly milder in its wake mid week, then much
colder late week.

&&

.NEAR TERM /THROUGH SUNDAY/...
As of 145 PM Saturday...

As expected the stratus has held firm today as cirrus overspreads
the area ahead of the next system. Even though some of this
stratus will lift as the low level flow turns more SE, this will
keep temps from dropping much tonight so another day of going
above guidance for lows.

A southern stream system will approach Sunday in the form of a
surface wave with induced isentropic lift overspread the TN Valley
into SW VA. Given how dry the low levels are, this will fall as
virga initially before reaching the ground around sunrise. Thermal
profiles suggest some wet snow may fall on the highest ridges in
SW VA early Sunday morning but with little if any accumulation.
Most of the lift will slide into VA as the day progresses with a
S/W trof tracking thru the OH Valley. This combined with some
downsloping SE flow should leave much of the area dry as the
shadow and dry air keep any precip as virga until late in the day.
Across the mountains, in particular Pocahontas County, light
precip will fall as a mixture with all snow on the ridges. Temps
on Sunday should manage to warm well into the 40s across the
Lowlands with 30s in the mountains.

&&

.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 345 PM Saturday...

Weak high pressure fills the void behind the Sunday/Sunday night
system as the flow aloft turns southwesterly in advance of the
next fast moving upper level low. In the cyclogenesis over the
lower Mississippi Valley, a warm front/baroclinic zone sets up
across the Tennessee Valley, bringing rain Monday night and
Tuesday. The system strength will likely peak as it moves into the
lower Ohio Valley, and then begin to fill as it continues
northeastward. Overall, going to be about a one half to one inch
type event, with the frontal boundary lingering from the mountains
back into the lower Mississippi Valley.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 345 PM Saturday...

Strong cold front arrives Thursday with an amplification to the
synoptic scale pattern and a sharpening of the low level
temperature gradient. Thunder potential is on the lower side right
now, but will need to watch this as the event approaches. Likely
to see some wind, and a cold airmass at -16C at 850mb will advect
into the middle Ohio Valley and central Appalachians. Upslope snow
likely to follow through the weekend.

&&

.AVIATION /21Z SATURDAY THROUGH THURSDAY/...
As of 200 PM Saturday...

Widespread MVFR cigs mainly across the mountains of WV, and north
central WV through the late afternoon. Otherwise, a general
improvement to low VFR much of the area this evening, although
MVFR cigs may continue to linger across parts of the higher
terrain including at site KEKN.

A system approaches from the SW on Sunday with cigs gradually
lowering into MVFR across KBKW. Light rain will try to overspread
the area but dry air in the low levels will keep much of this
across SW VA and the E Slopes, where a light wintry mix is
expected, especially in the high terrain where IFR conditions will
develop.

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Timing of category changes in clouds may
vary this evening.

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
EST 1HRLY       13   14   15   16   17   18   19   20   21   22   23   00
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  M    H    H    H    H    H    H    H    H    H    H    M
EKN CONSISTENCY  M    M    M    M    M    M    M    M    M    M    M    L
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
CKB CONSISTENCY  M    M    M    H    M    M    M    M    H    H    H    M

AFTER 18Z SUNDAY...
IFR possible in rain and snow, particularly in the mountains
Sunday night into Monday. Additional IFR possible in rain and snow
towards mid week.

&&

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

&&

$$
SYNOPSIS...30/26
NEAR TERM...30
SHORT TERM...26
LONG TERM...26
AVIATION...30



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