024
FXUS61 KRLX 210538
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
138 AM EDT Sat Sep 21 2024

.SYNOPSIS...
Mostly dry and warm under high pressure. A weak system passes
through over the weekend, and may trigger a few showers over and
near the mountains on Saturday.

&&

.NEAR TERM /THROUGH TODAY/...
As of 900 PM Friday...

No major changes were made to the overnight forecast as things
appear to be largely on track. Still expect some river valley
fog to develop, but outside of the high valleys, there`s some
uncertainty on the extent of the fog, so the day shift`s fog
forecast was left as-is.


As of 120 PM Friday...

Mostly dry conditions expected tonight as a surface high pressure
slides east of the Appalachians. Patchy dense fog will be
possible once again, along the most protected river valleys. Any
fog will quickly dissipate by 9 AM Saturday morning.

A weak shortwave, evident at H700, will push a cold front Saturday
morning with isolated light showers, as shown by a few of the
deterministic models. Therefore, added low PoPs for the onset of
precipitation Saturday morning across SE OH, spreading east
across WV through the afternoon. Then, aided by afternoon
heating, showers and thunderstorms should develop across the
area into the evening hours. Moderate instability with CAPE
reaching 1,800 J/kg and PWATs +2 standard deviation from the
mean suggest storms may produce localized heavy downpours. In
addition, dry air in the mid levels may allow for strong
downburst capable to produce damaging winds. SPC has most of the
area under general thunder, and a marginal risk for severe
thunderstorms across the northeast mountains for Saturday.

Tonight`s lows will range from the low to mid 60s lowlands, into the
mid 50s northeast mountains. Highs on Saturday will reach the lower
90s across the lowlands, ranging into the lower 70s northeast
mountains.

&&

.SHORT TERM /TONIGHT THROUGH SUNDAY NIGHT/...
As of 952 AM Friday...

An upper-level ridge will briefly move over the area Sunday with the
return of dry, hot, and sunny weather areawide. Increased fire
danger will return Sunday afternoon, especially in the lowlands,
with afternoon minimum RH values expected to range from 30-40%
across the central and northern WV lowlands and portions of
southeast OH. High temperatures will reach the lower 90s across much
of the lowlands during the afternoon. Rain chances will slowly
increase from west to east Sunday night as 500-mb heights lower and
the next low pressure system approaches. The best chance of showers
Sunday night into Monday morning will be across southeast Ohio.

&&

.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 952 AM Friday...

A wave of low pressure will track into the Great Lakes Monday with a
trailing cold front moving into the Ohio Valley. This will bring
more moisture into the area with afternoon minimum RH only expected
to drop to 50-60% across the WV lowlands and southeast OH. This
should mitigate the fire threat. In addition, shower chances will
return, with the greatest chances across northern WV and southeast
OH.

The rest of the week looks unsettled with chances of rain just about
each day as waves of mid-level vorticity flow along the approaching
trough. Given our drought situation, this is good news. Another
cutoff upper-level low is expected to develop by the middle of next
week, over the midwest or the Great Lakes, with not much movement
expected through the end of next week. This should bring daily
chances of showers for our region. Confidence is still low at this
time, but there is potential for some beneficial rainfall.

&&

.AVIATION /06Z SATURDAY THROUGH WEDNESDAY/...
As of 140 AM Saturday...

Pockets of FEW to SCT mid-level clouds will mitigate river
valley fog from seeping away from the mountains overnight.
Therefore, continue to portray a similar tale to the previous
forecast with only EKN having the potential for IFR vsbys
through early Saturday morning.

A weak cold front passes through the area on Saturday, bringing
a broken deck of clouds and the chance for mountain
showers/storms in the afternoon. Airfields should remain VFR
during this timeframe, but VCSH/VCTS was included for sites
close to forecast POPs for this afternoon and evening.

In the wake of the front, better potential for fog to ooze down
into the lowlands will transpire. This will be especially true
for areas that receive rain.

Calm winds overnight will shift out of the west/northwest for
the second half of the day Saturday in response to FROPA.

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Timing and extent of 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                                             SAT 09/21/24
UTC 1HRLY       03   04   05   06   07   08   09   10   11   12   13   14
EDT 1HRLY       23   00   01   02   03   04   05   06   07   08   09   10
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  H    H    H    L    L    M    M    M    M    M    M    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H

AFTER 06Z SUNDAY...
IFR conditions possible Sunday morning with river valley fog in
some of the higher valleys around the area.

&&

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

&&

$$

SYNOPSIS...FK/ARJ/JMC
NEAR TERM...FK/ARJ
SHORT TERM...JMC
LONG TERM...JMC
AVIATION...MEK