National Weather Service National Headquarters

• Home
• Site Map
• News
• Organization
• Search for: NWS All NOAA 

-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 271034
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
634 AM EDT Thu Jun 27 2019

.SYNOPSIS...
Weak high pressure remains today, but a hotter and more humid
day lends to a slight chance of storms. Somewhat higher chances
for afternoon and evening storms return Friday into next week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 630 AM Thursday...

No changes made to the forecast at this time; satellite shows
widespread river valley fog across southern and interior West
Virginia, southwest VA, and in some portions of the Tristate of
KY/WV/OH.

As of 315 AM Thursday...

Same general weather set up today as yesterday, with weak high
pressure centered over southern Appalachia. Temperatures reach
upwards of 90 for portions of the Ohio Valley and western
lowlands with muggy dew points near 70. The caveat to high
pressure today is that with warmth and moisture continuing to
trend upward, corresponding with increased ridging into the
Plains, instability grows, paving the way for scattered
convection in spite of weak shear and dynamic fields. A
disturbance in the NW flow separating us from the growing ridge
offers a bit of surface convergence in the Ohio Valley, which
would serve as the focus for any convection this afternoon and
evening, along with the elevated heat source of the mountains to
some extent.

Weak winds through the column don`t leave much in the way of storm
motion or organization, strong instability in the neighborhood of
3000 J/kg MLCAPE will lead to explosive development, and PWAT around
1.5" will lead to at least localized heavy downpours where low level
convergence is maximized. Overall, expecting isolated to scattered,
slow-moving, short-lived convection. While wind profiles don`t
support significant hail growth, heavy rain and DCAPE exceeding
1000 J/kg supports at least isolated gusty winds under cells.

Tonight, enough moisture may pool near the weak wave over the
Ohio Valley to create some low-level stratus, otherwise
expecting another humid night with at least patchy fog except
where low- level clouds form.

&&

.SHORT TERM /FRIDAY THROUGH SATURDAY NIGHT/...
As of 249 AM Thursday...

Little change to previous forecast reasoning. Height fields are
prog to be the highest on Friday with a hot, humid, and stagnant
air type of day. Heat indices may briefly flirt with advisory
levels in the immediate downtown urban areas, but most areas in
general should remain below Heat Advisory thresholds. If temps
warm enough, then isolated diurnally driven afternoon/early
evening convection may occur.

Height fields lower slightly on Saturday and moisture depth in
the atmospheric column is prog to be slightly greater. Thus,
slightly higher convective coverage may occur in the afternoon,
especially in near the mountains...with hot and humid conditions
prevailing again across the region.

&&

.LONG TERM /SUNDAY THROUGH WEDNESDAY/...
As of 257 AM Thursday...

CWA becomes located on the northern edge of mid level ridging
for much of the Long Term period with several vort maxes
advecting across/near the region during this time frame.
Combination of these disturbances and daily high heat/humidity
should result in convective chances nearly every afternoon and
evening.

&&

.AVIATION /12Z THURSDAY THROUGH MONDAY/...
As of 640 AM Thursday...

A couple leftover fog restrictions this morning will lift in
the coming hour or so, yielding to prevailing VFR conditions
through today. Light and variable winds this morning will
increase to 5-10 kts from the west southwest by the afternoon,
more westerly at BKW. There is a slight chance for storms this
afternoon mainly in the Ohio Valley including HTS/PKB, and to a
lesser extent EKN with mountain-based storms possible. At this
time only have it included for the Ohio Valley.

Tonight, winds go light and variable by 00Z and calm shortly after
sunset. Look for another night of river valley fog perhaps impacting
TAF sites should it be deep enough; guidance also hints at the
development of low-level stratus across the Ohio Valley. At any
rate, another night of restrictions is possible.

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

FORECAST CONFIDENCE: High for VFR prevailing during the day
Thursday. Medium for restrictions tonight.

ALTERNATE SCENARIOS: Timing and duration of fog/low stratus
tonight may vary. A non-zero threat for storms exists at every
site, and storms would produce brief drops in visibility and
gusty winds.

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       10   11   12   13   14   15   16   17   18   19   20   21
EDT 1HRLY       06   07   08   09   10   11   12   13   14   15   16   17
CRW CONSISTENCY  L    M    L    L    H    H    H    H    H    H    H    H
HTS CONSISTENCY  M    M    L    L    H    H    H    H    H    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    H
EKN CONSISTENCY  M    M    L    M    H    H    H    H    H    H    H    H
PKB CONSISTENCY  L    M    L    M    H    H    H    H    H    H    H    H
CKB CONSISTENCY  L    L    L    H    H    H    H    H    H    H    H    H

AFTER 12Z FRIDAY...
IFR possible in afternoon and evening storms Friday into the
next week.

&&

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

&&

$$
SYNOPSIS...RH/MC
NEAR TERM...MC
SHORT TERM...RH
LONG TERM...RH
AVIATION...MC