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 221905
AFDRLX

Area Forecast Discussion
National Weather Service Charleston WV
303 PM EDT Tue Aug 22 2017

.SYNOPSIS...
Strong cold front with strong to possibly severe storms into
tonight. Cooler and drier high pressure into the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 3 PM Tuesday...

A rather classic set up for severe weather presents itself this
afternoon and evening. A strong cold front extended from
southeast MI to southern IL early this afternoon. In an axis
ahead of it, surface dew points into the lower 70s, CAPE of 1500
to 2000 J/kg and 45 to 50 kts of deep layer bulk shear provide
ample potential for severe weather for late August, especially
given prime heating time.

Already approaching the Ohio River as of early afternoon, the
severe threat continues through the evening hours, well out
ahead of the advancing cold front. The severe threat will end
prior to the frontal passage on loss of heating and of some
dynamics. The front itself reaches the Ohio River around
midnight, and then crosses the remainder of the forecast area by
dawn Wednesday. After low clouds and some fog to start, drier
northwest flow will bring cooler and less humid weather
Wednesday.

Temperatures looked to be on track given the latest guidance
and weather pattern, notwithstanding wet bulb cooling, which led
to a somewhat lower than guidance forecast for early tonight.

&&

.SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/...
As of 230 PM Tuesday...

High pressure builds into the region Wednesday night for drier
weather. Looking to overall be a dry period, with warm sunny
days, and foggy mornings under high pressure. A shortwave trough
will affect the area on Thursday, which could create a few light
showers or sprinkles, but overall, main threat for this appears
to be low, and to our north. It will however, bring in an
additional shot of cooler air.

Overall, will be nice weather, with the much cooler and less
humid conditions, and sunny weather.

&&

.LONG TERM /SATURDAY THROUGH TUESDAY/...
As of 230 PM Tuesday...

Most of the extended period will remain dry, although there will
be a slight chance to chance for showers and thunderstorms,
mainly across the higher terrain, possibly drifting westward
into the lowlands. Expecting a slight increase in temperatures
from the short term.

&&

.AVIATION /19Z TUESDAY THROUGH SUNDAY/...
As of 3 PM Tuesday...

A strong cold front moves across the area late this afternoon
and tonight, well preceded by a line of strong to severe
thunderstorms.

After the VFR warm sector start, timing on line of TSTMS has
not changed much. After reaching the Ohio River near 19Z, it is
expected to arrive at CKB-CRW line around 23Z and into the
mountains 01Z-02Z. Conditions can lower to IFR at times in
heavy rain, with very strong gusty west winds possible.

Low level moisture will follow the front overnight, mainly on
IFR stratus, but some fog is also possible. Dry low level
northwest flow will allow this moisture to mix out quickly
Wednesday morning.

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Main line of storms with cold front
could arrive a bit earlier than forecast. MVFR to IFR conditions
in low level moisture overnight tonight into Wednesday morning
could vary.

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       15   16   17   18   19   20   21   22   23   00   01   02
EDT 1HRLY       11   12   13   14   15   16   17   18   19   20   21   22
CRW CONSISTENCY  H    H    H    H    H    M    M    M    H    H    H    H
HTS CONSISTENCY  H    H    M    M    M    M    M    M    H    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    M    M    H
EKN CONSISTENCY  H    H    H    M    M    M    M    M    H    H    H    H
PKB CONSISTENCY  H    H    M    M    M    H    H    H    H    H    H    H
CKB CONSISTENCY  H    H    M    M    M    M    M    H    H    H    H    H

AFTER 18Z WEDNESDAY...
River valley fog possible each morning through the weekend.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...None.
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.