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000
FXUS61 KRLX 060244
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
1044 PM EDT Thu Aug 5 2021

.SYNOPSIS...
Slow moving convection today amid building high pressure.
Gradual warming trend continues into early next week with
isolated to scattered afternoon showers and thunderstorms.

&&

.NEAR TERM /THROUGH FRIDAY/...
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As of 1042 PM Thursday...

With calm winds across the area and mainly clear skies, valley
fog is expected to develop over the next few hours across parts
of the region. Overall coverage of fog overnight should be less
than last night, especially since most areas did not receive
any measurable precipitation earlier today due to the very isolated
nature of the activity. While recent satellite imagery shows
that high clouds are approaching the area ahead of a upper
trough to the west, this shouldn`t have too much of an impact on
overall fog development since it should be able to develop
before any thicker cloud cover moves in towards Friday morning.

As of 629 PM Thursday...

Convection has mostly tapered off across the region, but some
isolated activity remains for now across southeast OH and over
the mountains. This activity should continue to diminish as
instability decreases and the upper trough aloft departs
further to the east. Other than some minor tweaks to PoPs based
on latest radar trends, the forecast remains on track.

As of 220 PM Thursday...

Diurnally driven pulse showers and storms have blossomed across
areas east of the Ohio River this afternoon. Weakening upper
level flow aloft in response to a departing trough will
deplete the movement of convection today, but should generally
propagate north/northeastward before diminishing with the loss
of daytime heating. Lingering moisture will prompt river valley
fog Friday morning.

The departure of the trough will allow for a mid to upper level
ridge axis and its adjoining building heights to spread drier
conditions overhead overnight into Friday. Increasing moisture
return via southwesterly low level flow will promote increased
cloudiness as the day wears on Friday. This low level flow
regime will also advertise slightly warmer afternoon highs on
Friday, with some areas in the lowlands sneaking up near 90
degrees.
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&&

.SHORT TERM /FRIDAY NIGHT THROUGH SATURDAY NIGHT/...
As of 230 PM Thursday...

Shortwave swings across the region Friday night into Saturday.
Instability is not terribly high during the day Saturday with
negligible shear but scattered showers and thunderstorms are a
good bet, diminishing quickly Saturday evening as the shortwave
pushes to our east. Temperatures on Saturday will be heavily
dependent on cloud cover and precip coverage, but highs in the
mid 80s are forecast for the lower elevations.

&&

.LONG TERM /SUNDAY THROUGH THURSDAY/...
As of 230 PM Thursday...

Models develop upper level ridging over the region early next
week signaling a return to typical summer-time heat and
humidity. Highs each day through the period should be in the
upper 80s to lower 90s in the lower elevations, with dewpoints
rising again toward the uncomfortable 70 degree level. Theres
not much to force convection besides daytime heating and
topography so PoPs will be nil or low early in the week. Towards
midweek, models diverge quite a bit, but in general point to a
more active regime with upper level troughing setting up over
our region or just to our west. This results in higher chances
for showers/storms Tuesday through Thursday, especially during
the afternoon and evening hours.

&&

.AVIATION /03Z FRIDAY THROUGH TUESDAY/...
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As of 720 PM Thursday...

VFR conditions will be in place area-wide this evening, but
flight conditions are expected to deteriorate overnight as
valley fog develops. If valley fog develops in close enough
proximity to any terminals, then a prolonged period of IFR/LIFR
conditions will be possible overnight. Any fog that does
develop should dissipate around 12Z-13Z Friday and VFR
conditions will then prevail Friday afternoon and evening as
high pressure will be in control. In addition, surface winds
will be out of the SW on Friday, mainly around 5 kts throughout
the day.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SATURDAY...

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Timing, duration, and coverage of fog
overnight 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 08/06/21
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    L    L    L    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    H    M    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  H    H    H    H    L    M    L    L    L    L    M    H
PKB CONSISTENCY  H    H    H    H    H    H    H    H    M    H    H    H
CKB CONSISTENCY  H    H    H    H    H    L    M    M    H    H    H    H

AFTER 00Z SATURDAY...
IFR restrictions may be possible Saturday morning.
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&&

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

&&

$$
SYNOPSIS...ABE/MEK
NEAR TERM...RG/MEK
SHORT TERM...ABE
LONG TERM...ABE
AVIATION...RG