Area Forecast Discussion
Issued by NWS Charleston, WV

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895
FXUS61 KRLX 091130
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
730 AM EDT Thu Oct 9 2025

.SYNOPSIS...
A large high drifts by north of the region today through Friday.
This will lead to clear sky, and mountain valley frost tonight.
Coastal low forms and moves up the coast this weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 730 AM Thursday...

GOES-R nighttime microphysics imagery shows that river valley
fog has become confined mainly to valleys in and near the
mountains, and an update to the SPS largely reflected this.
Meanwhile, there was frost in at least a few locations in and
near the northern mountains this morning.

As of 310 AM Thursday...

GOES-R nighttime microphysics imagery evinces river valley fog
across southern portions of the area, and on up the mountains.
Issued an SPS earlier to cover this. Expect the fog to persist
through daybreak before burning off.

The frost advisory appears to be on track, as guidance suggests
low level flow diminishing early this morning with surface high
pressure ridging down the mountains.

The high will drift by to the north of the area this period,
providing dry weather with nary a cloud. Dry advection will
result in lower afternoon dew points and relative humidity
percentages compared with Wednesday, the latter in the 30s.
However, surface flow will be light.

Ridging extending south from the high, although anchored to the
mountains, will be farther east tonight compared with this
morning on account of the high moving east. This will allow for
slightly stronger low level flow, with less fog.

After the chilly start, the coldest of the season so far,
temperatures top out a bit below normal today, in the mid to
upper 60s across the lowlands and mid 50s to mid 60s in the
mountains. Tonight will eclipse this morning as the coldest of
the season so far, save perhaps for hilltops in the southern
cold fields. However, with the slightly increased low level
flow, expect only a few of the notoriously coldest mountain
valley locations to experience a freeze, and, in collaboration
with neighbors, opted to hold with the Freeze Watch in our side
of the mountains for now.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY/...
As of 400 AM Thursday...

The surface high will continue its eastward progression, moving
off the northeast coast by Saturday. This will allow a
southerly return flow to establish and strengthen across the
region. Aloft, the upper trough will lift out, replaced by a
ridge on Friday. However, that ridge gives way to a small
mid/upper-level low dropping south through the Great Lakes on
Saturday. Meanwhile, a weak, broad southern stream short wave
trough along the southeast coast generates surface cyclogenesis
off the southeast coast Saturday.

Dry weather will continue, with a modest warming trend. Lowland
highs will return to the lower 70s for Friday, and then reach
the mid 70s for Saturday. Friday night will see a corresponding
moderation in temperatures, and the frost threat will be
significantly diminished, with lows in the northern mountain
valleys in the upper 30s.

&&

.LONG TERM /SATURDAY NIGHT THROUGH WEDNESDAY/...
As of 400 AM Thursday...

The long-term period continues to feature a complex but
interesting synoptic setup. Saturday night through Sunday
night, the mid/upper-level low dropping south out of the Great
Lakes phases with the southern stream short wave trough,
resulting in rapid intensification of the coastal low that
forms Saturday, and its tracking up the east coast. By Monday, a
rather intense, stacked low pressure system may be centered
right along or just off the middle Atlantic seaboard.

While precipitation directly associated with the coast storm
may not directly impact the forecast areas, showers from the
upper-level low dropping south out of the Great Lakes are
possible across northern/eastern portions of the area Saturday
night through Sunday night.

The coastal low fills and drifts offshore Monday night through
the middle of next week, and ridging surface and aloft becomes
reestablished over the forecast area, providing dry weather,
with near seasonable and steady temperatures. A Rex block shown
to slow the coastal system down early next week in earlier
model runs is not really shown to set up now.

Later next week, models indicate another mid/upper-level low
dropping south out of eastern Canada and through the eastern
Great Lakes, re-invigorating the coastal low. While all this
happens offshore, the ECMWF has this occurring much close to
the coast, just enough to bear watching for the mountains later
next week.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
As of 730 AM Thursday...

GOES-R nighttime microphysics imagery shows that river valley
fog had become confined mainly to valleys in and near the
mountains early this morning. The dense fog at EKN should be
gone by 14Z, and the intermittently dense fog at BKW should be
gone by 13Z. Mist is still possible at other sites during the
first hour or so of the forecast.

Otherwise high pressure will provide VFR conditions, with nary
a cumulus cloud this afternoon. Drier air coming in today, and
slightly increased low level flow, should limit fog formation
tonight, compared with early this morning. Have coded VLIFR
dense fog formation later at EKN compared with early this
morning, 08-09Z, with none coded elsewhere. However, patchy low
stratocumulus may sneak into BKW before dawn Friday.

Light northeast surface flow today will veer to light east to
southeast tonight and become a bit gusty at BKW. Light north to
northeast flow aloft will gradually veer to east, southeast and
then south this period.

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

FORECAST CONFIDENCE: Medium to high.

ALTERNATE SCENARIOS: Burning off of fog early this morning may
vary a bit. Occurrence and timing of fog formation at EKN
overnight tonight may vary, and it is not out of the question
there is fog at another site or two overnight tonight.

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       11   12   13   14   15   16   17   18   19   20   21   22
EDT 1HRLY       07   08   09   10   11   12   13   14   15   16   17   18
CRW CONSISTENCY  L    L    M    H    H    H    H    H    H    H    H    H
HTS CONSISTENCY  M    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  L    L    L    L    H    H    H    H    H    H    H    H
PKB CONSISTENCY  M    H    H    H    H    H    H    H    H    H    H    H
CKB CONSISTENCY  M    H    H    H    H    H    H    H    H    H    H    H

AFTER 12Z FRIDAY...
At least patchy IFR valley fog is possible each morning.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Frost Advisory until 9 AM EDT this morning for WVZ039-040-
     518>526.
     Freeze Watch from late tonight through Friday morning for
     WVZ523>526.
OH...None.
KY...None.
VA...None.

&&

$$

SYNOPSIS...TRM
NEAR TERM...TRM
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...TRM