790
FXUS61 KRLX 260746
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
346 AM EDT Sat Jul 26 2025

.SYNOPSIS...
High pressure continues a stretch of hot and humid weather with
the chance for mainly afternoon and evening showers and storms
with localized downpours. A cold front arrives late next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 315 AM Saturday...Corrected for web output artifacts

The latest satellite and surface observations show a very moist
and unstable airmass already in place across the forecast area.
Early morning temperatures are hovering in the low to mid 70sF
with dew points in the low 70sF. The synoptic feature of note
is a robust 596 dm h5 ridge centered over the southeastern
states.

This setup will promote strong subsidence and compressional
heating, leading to a hot and humid day. Highs are forecast to
reach the low to mid 90sF for much of the lowlands, with 80sF
in the higher terrain. Even after lowering dew points a bit from
central guidance, the combination of these temperatures with
dew points in the low to mid 70sF will yield peak heat indices
between 100F and 105F. Confidence in widespread heat indices
exceeding 100F is high, and Heat Advisories have been issued
for much of the lowlands. Lows and dew points in the lower to
mid 70s will provide little relief overnight tonight.

Convection today will be isolated and diurnally driven. The
strong mid-level cap associated with the ridge will inhibit
widespread thunderstorm development. However, with MLCAPE values
climbing to 2500  3000J/kg and PWAT values of 1.75 to 2.0
inches, any storm that can break the cap will be capable of
producing localized damaging wind gusts via wet microbursts and
torrential rainfall.

The Storm and Weather Prediction Centers have Marginal Risks for
Severe Thunderstorms and Excessive Rainfall, respectively, for
northern portions of the forecast area today, where CAPE and
h85 theta e values are forecast to be greatest, and there is
nominal 0-6 and 0-8 km bulk shear of 20 kts. Overall, however,
this weak deep-layer shear will keep storm organization, and the
sever threat, low.

While convection is most likely during the afternoon and early
evening hours, rich low to mid level moisture will allow adequate
instability based just above the surface tonight, keeping
showers and thunderstorms possible then as well.

&&

.SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/...
As of 315 AM Saturday...

The mid/upper-level ridge over the southeast retrogrades
westward to the lower and mid Mississippi Valley and southern
plains this period. With this ridge actually extending down to
h85, flow from there up veers to northwest over the forecast
area.

A weak mid-level short wave trough moving southeast across the
area Sunday increases the likelihood for mainly afternoon and
evening showers and thunderstorms. Ridging becomes more
dominate in this flow regime on Monday, but possible
perturbations in the mid level flow, and the ongoing orographic
lift and mesoscale boundaries could still trigger mainly
afternoon and evening showers and thunderstorms.

The thunderstorm threat remains similar to today. The
thermodynamic environment will be just as, if not more,
explosive. Any storm that fires will pose a threat for localized
damaging winds and flash flooding, especially on Sunday, when
the Storm Prediction center carries a Marginal Risk for Severe
Thunderstorms across northeast portions of the area. The threat
at least becomes more isolated on Monday.

The absence of a surface front leaves temperatures and dew
points at warm and humid levels, although increased cloud and
showers and thunderstorm coverage lowers afternoon highs a bit
on Sunday. However, highs climb back a bit on Monday, and the
high humidity keeps peak afternoon heat indices up around heat
advisory criteria on Sunday and especially on Monday. Lows and
dew points in the lower to mid 70sF will provide little relief
at night.

By Monday night, the global models begin to show the first
signs of the upstream trough digging into the Northern Plains,
which signals the beginning of the end of the ridge`s dominance.

&&

.LONG TERM /TUESDAY THROUGH FRIDAY/...
As of 315 AM Saturday...

Tuesday will be another very hot and humid day, with highs
in the lower to mid 90sF, with heat indices in the lower
100sF.

The main focus of the long term is the significant pattern
change arriving mid to late week. Both the GFS and ECMWF, along
with their respective ensembles (GEFS/EPS), show strong
agreement in a deep upper-level trough digging into the eastern
U.S. This will drive a cold front toward the region. Timing
differences exist, but the general solution is for the front to
approach the middle Ohio Valley on Wednesday, and then cross
the central Appalachians on Thursday.

Ahead of the front on Wednesday, increasing large-scale ascent
and low-level moisture convergence will lead to a higher
coverage of showers and thunderstorms. With increasing deep-
layer shear, some storms could become organized, likely
enhancing the severe weather threat. Confidence in Severe
Thunderstorms is MEDIUM for Wednesday and Thursday. All modes of
severe weather could be possible depending on the precise
timing of the front.

The slow movement of the front combined with the deep tropical
moisture (high PWATs) will also increase the threat for
excessive rainfall. Confidence in Excessive Rainfall is MEDIUM
for the Wednesday-Thursday timeframe.

The front is expected to clear the entire area by Friday
morning. Behind it, a much cooler and drier Canadian airmass
will advect into the region on refreshing northerly winds.

The heat wave may peak ahead of the front on Wednesday, with
in the mid to upper 90sF, with heat indices in the lower to mid
100sF. The front, or at least increased cloud and shower and
thunderstorm coverage, will suppress highs on Thursday. Nights
will remain warm and sultry through mid week.

High temperatures on Friday and next Saturday will be
noticeably lower, falling into the low to mid 80sF, with 70sF
over the higher terrain. Dew points and low temperatures will
drop into the 50sF and 60sF, providing significant relief.
Confidence in the heat wave breaking by late next week is HIGH.
The primary uncertainty is the exact timing of the frontal
passage (Wednesday night vs. Thursday), but the overall pattern
change is a high-confidence forecast.

&&

.AVIATION /08Z SATURDAY THROUGH WEDNESDAY/...
As of 315 AM Saturday...

Thunderstorms across the north Friday afternoon were encouraging
fog formation there, although visibilities were fluctuating,
with no fog at all so far at CKB, the fog forecast through
daybreak there is highly uncertain. While CRW did not get any
rain, calm and clear conditions may still allow valley fog to
get to the terminal, so MVFR conditions were kept in for a few
hours leading up to sunrise.

Unlike on Friday, thunderstorms this afternoon and evening are
possible just about anywhere, but coverage is again forecast to
be isolated to scattered. LIFR in heavy rain, frequent lightning
and gusty winds are possible with any thunderstorm today. The
thunderstorms will again complicate the fog forecast for
tonight, especially given the chance for storms themselves will
not entirely vanish, given the very moist and unstable airmass
in place.

Surface flow will generally be light and variable to southwest,
except gusty and erratic in and near thunderstorms. Light west
to northwest flow aloft early this morning will become light
southwest by this afternoon, and then remain that way through
tonight.

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Timing and extent of restrictions in fog
early this morning and overnight tonight may vary. Amendments
may be needed for direct impacts from thunderstorms this
afternoon and evening.

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 07/26/25
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    H    M    M    M    L    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    M    M    H    H
EKN CONSISTENCY  H    L    L    M    M    M    L    H    H    H    H    H
PKB CONSISTENCY  M    L    L    M    M    M    M    H    H    M    M    H
CKB CONSISTENCY  L    L    L    M    L    M    L    H    H    M    M    H

AFTER 06Z SUNDAY...
IFR conditions possible in showers and thunderstorms again Sunday
afternoon and evening, which in turn could lead to IFR fog
overnight Saturday night into early Sunday morning, and
overnight Sunday night into early Monday morning.

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for WVZ005>011-013>020-026>031.
OH...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for OHZ066-067-075-076-083>087.
KY...Heat Advisory from 11 AM this morning to 8 PM EDT this evening
     for KYZ101>103-105.
VA...None.

&&

$$

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