Area Forecast Discussion
Issued by NWS Charleston, WV

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
000
FXUS61 KRLX 181131
AFDRLX

Area Forecast Discussion
National Weather Service Charleston WV
631 AM EST Thu Jan 18 2018

.SYNOPSIS...
With high pressure passing south of the area, a southwest flow
will bring milder air today through the weekend, with a warm
front passing Saturday. A cold front crosses late Monday.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 630 AM Thursday...

Delayed clearing in the mountains until the low level moisture
mixes out and the upslope component of flow diminishes later
this morning.

As of 350 AM Thursday...

Arctic air mass, represented by high pressure over the
southeastern states, modifies as that high drifts slowly
eastward during the near term period, and beyond. In the
meantime, a southwest flow of milder air had already become
established over the forecast area, with rising temperatures
over the hill and ridgetops early this morning.

The stratocu in and near the mountains will be eradicated this
morning, as the moisture mixes out, and the westerly flow there
backs, diminishing the upslope component. The remainder of the
forecast is dry with a mainly clear sky, with a dry column,
even as upper level ridging gives way to a short wave trough
passing by to the north of the area tonight.

Temperatures do rise slowly today overtop the snow cover and
beneath a low inversion, with wind chills rising above the -10F
advisory threshold by 10 AM. Leaned on the lower side of
guidance, with highs just making it above freezing across the
southern lowlands this afternoon. It will be noticeably less
cold compared with one of the coldest days of the winter
Wednesday.

Lows tonight close to the MET, except lower in the valleys, but
not quite as low as the MAV. The persistent pressure gradient
will make for only somewhat of a ridge / valley split tonight,
as even the valleys are not likely to stay decoupled through the
night. Lows generally in the teens, compared with the widepsread
single digits of early this morning, reflect the ongoing
retreat of the arctic air.

&&

.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
As of 350 AM Thursday...

Warm and mostly dry during the short term period with high pressure
in control. A warm frontal boundary associated with low pressure
moving northeast out of the Plains will lift north across the area
late Saturday night into Sunday, with light showers forming as it
does so.

&&

.LONG TERM /MONDAY THROUGH WEDNESDAY/...
As of 350 AM Thursday...

Cold front associated with aforementioned low will sweep across the
forecast area on Monday, with rain developing area wide. Good
moisture fetch associated with system, with PW values progged to
rise to around an inch, will result in decent rain totals, with qpf
values around 0.75 inches or more area wide. Any lingering
precipitation will change over to light rain and snow showers Monday
night, continuing into Tuesday, with light accumulations possible.
Wednesday looks to be dry with more seasonal temperatures.

&&

.AVIATION /11Z THURSDAY THROUGH MONDAY/...
As of 630 AM Thursday...

MVFR to IFR stratocu in the mountains will mix out later this
morning, and the last of the snow flakes will go with it.
Otherwise arctic high pressure passing south of the area will
then bring VFR weather, a with mainly clear sky.

Light southwest surface flow, west to northwest on the ridges,
will strengthen and become a bit gusty today, before becoming
light again tonight. Flow aloft will be moderate northwest into
tonight, and then become moderate west overnight.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...

FORECAST CONFIDENCE: Medium to high.

ALTERNATE SCENARIOS: Timing of MVFR/IFR stratocu dissipation may
vary this morning. Wind directions and gusts will fluctuate
this afternoon.

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.

DATE               THU 01/18/18
UTC 1HRLY       10   11   12   13   14   15   16   17   18   19   20   21
EST 1HRLY       05   06   07   08   09   10   11   12   13   14   15   16
CRW CONSISTENCY  M    M    M    H    H    H    H    H    H    H    M    M
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    M    M
BKW CONSISTENCY  M    H    M    H    H    H    H    H    H    H    M    M
EKN CONSISTENCY  L    L    L    H    H    H    H    H    H    H    M    M
PKB CONSISTENCY  H    H    L    H    H    H    H    H    H    H    M    M
CKB CONSISTENCY  M    M    M    M    H    H    H    H    H    H    M    M

AFTER 12Z FRIDAY...
None.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Wind Chill Advisory until 9 AM EST this morning for WVZ520-
     522>526.
OH...None.
KY...None.
VA...None.

&&

$$
SYNOPSIS...TRM/SL
NEAR TERM...TRM
SHORT TERM...SL
LONG TERM...SL
AVIATION...TRM



USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.