654
FXUS61 KRLX 200635
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
235 AM EDT Fri Sep 20 2024

.SYNOPSIS...
A few showers and storms may develop along the mountains this
afternoon, but otherwise mostly dry and warm under high
pressure. A weak system passes through over the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 235 AM Friday...

Surface high pressure slides slightly eastward today, but
retaining enough influence over the forecast area that will
yield mostly dry weather through the period. Early morning
microphysics satellite imagery shows river valley fog underway
along the higher terrain and is expected to spread further down
into the lowlands before dawn.

Any fog development this morning will gradually erode after
sunrise and give way to afternoon cumulus, especially along the
mountains. Additional growth along the higher terrain may foster
isolated showers and storms during peak heating hours.

Otherwise, above seasonable temperatures prevail across the
Central Appalachians today, with a few areas within the Tri-
State area and along the I-64 corridor reaching the low 90s. A
slight dip in dew points during the afternoon will bring
relative humidity values down into the 30 percent range across
the lower elevations. Light surface flow will be present
throughout the day, but dry fuels may attempt to stimulate fire
weather concerns in areas that have not received measurable
precipitation in quite some time.

A cold front marching into the Ohio Valley late tonight will
stem from a weakening disturbance north of the United States
border. Latest model runs depict a delay in showers entering the
forecast area within the valid forecast period, so opted to
trend back POPs overnight. Otherwise, another decent signal for
mountain fog seems plausible for late tonight into early
Saturday morning.

&&

.SHORT TERM /SATURDAY THROUGH SATURDAY NIGHT/...
As of 1207 PM Thursday...

The pattern to start this weekend will feature a weakening upper-
level low across northern New England, a ridge over the Ohio Valley,
and another low pressure system developing in the Rockies.
Saturday should be dry for the most part, but there is a small
chance of a few afternoon pop- up showers over the West Virginia
higher elevations with weak shortwave energy passing through
the ridge. We only give this a 20-30% chance of occurring. The
summer- like heat will be back in full force with highs expected
to reach the lower 90s across the lowlands. The more
comfortable spots will be in the higher mountain ridges, where
afternoon temperatures will be in the 70s-80s.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 1208 PM Thursday...

A warm front will pass through the area Sunday into Monday as the
aforementioned low pressure system, which developed over the Rockies
Saturday, tracks eastward. Models are generally dry over our area
for Sunday, with rain chances returning Monday as a stronger mid-
level wave of energy from the aforementioned low approaches
from the northwest. Rain chances will continue into Tuesday as
a cold front approaches from the west. Models begin to diverge
from Wednesday onward, but we opted to forecast near central
guidance, which suggests at least some chances of rain
Wednesday and Thursday next week. After starting the week
unseasonably hot across the lowlands, temperatures may trend a
few degrees below average for mid-to-late week with a potential
upper- level low somewhere over the East. Plenty of uncertainty
in the long-term forecast, so our confidence remains low.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
As of 140 AM Friday...

Nighttime satellite imagery at the time of writing exposed river
valley fog taking shape across the higher terrain of West
Virginia. This trend is expected to ooze down into the lowlands
as the overnight period progresses, impacting most TAF sites
outside of BKW. IFR/LIFR were included at most airfields for
early Friday morning, then branching out into VFR once more
after daybreak. Little to no obstructions are expected during
the day Friday, but a few afternoon showers/storms may sprout
along the mountains. There is another decent signal for fog late
tonight into Saturday morning that will be mentioned in more
detail with future issuances. Winds remain light and variable
today.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z SATURDAY...

FORECAST CONFIDENCE: Low this morning within fog; becoming High
after daybreak.

ALTERNATE SCENARIOS: Timing and extent of dense fog 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.

DATE                              FRI 09/20/24
UTC 1HRLY       06   07   08   09   10   11   12   13   14   15   16   17
EDT 1HRLY       02   03   04   05   06   07   08   09   10   11   12   13
CRW CONSISTENCY  H    L    L    M    M    M    M    L    H    H    H    H
HTS CONSISTENCY  H    H    L    L    L    L    L    H    H    H    H    H
BKW CONSISTENCY  H    H    L    L    L    L    H    H    H    H    H    H
EKN CONSISTENCY  L    L    L    M    M    M    M    L    H    H    H    H
PKB CONSISTENCY  H    H    L    M    M    M    M    L    H    H    H    H
CKB CONSISTENCY  H    H    L    M    L    L    L    H    H    H    H    H

AFTER 06Z SATURDAY...
IFR conditions possible Saturday and Sunday morning along the
higher terrain from river valley fog.

&&

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

&&

$$

SYNOPSIS...JRM/MEK
NEAR TERM...MEK
SHORT TERM...JMC
LONG TERM...JMC
AVIATION...MEK