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000
FXUS61 KRLX 230713
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
313 AM EDT Fri Aug 23 2019

.SYNOPSIS...
Cold front finally exits to the south today. High pressure with
dry, cooler weather for the weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 235 AM Friday...

In the midst of strengthening lower level 900-800mb
frontogenesis, so expect the coverage of showers to increase
through sunrise this morning. A weak wave of surface low
pressure is keeping the forward motion of the cold front to a
minimum but should see the front clear our portion of the
mountains after 15Z. The POPs continue in the wake of the front,
however, due to a 500mb axis embedded in the very broad
cyclonic flow over the Great Lakes. Much drier air at the
surface, lower, and mid levels moves in with this wholesale
airmass change once the wave aloft passes and high pressure
builds over the Great Lakes. Lower dewpoints tonight allow for
lows to drop back into a more comfortable range after a few days
of heat across the region.

&&

.SHORT TERM /SATURDAY THROUGH MONDAY/...
As of 313 PM Friday...

Mainly dry conditions are expected on Saturday due to the influence
of an expansive surface high centered in Quebec. However, can`t
completely rule out a few isolated showers/storms Saturday afternoon
in extreme southeastern zones where better quality moisture and
instability is expected (dewpoints in the low/mid 60s and CAPE
around 1,000 J/kg). The greatest chance of any precipitation will be
in southwest VA where low chance PoPs are in place. Elsewhere, the
atmosphere will be very dry with surface dewpoints in the mid/upper
50s, yielding PWATs between a half inch to an inch. With high
temperatures forecast to reach the upper 70s/low 80s, fantastic
weather is expected with comfortable humidity levels.

As the aforementioned high pressure shifts east towards the Canadian
maritimes on Sunday, return flow will give temperatures a boost of a
few degrees. This should translate to highs in the low 80s across
the lowlands on Sunday afternoon, just a degree or two below normal
for this time of the year. Upper ridge axis across the Great Lakes
should provide for a mainly dry forecast once again, but some low
PoPs are included across southern areas as a cut-off low rotates
east of the area in the Mid-Atlantic region. Regardless, with little
to no instability expected and subsidence in place, most of the
region should be dry.

By Monday, upper ridge axis continues to push to the east and a
shortwave trough will move across the Midwest. This leading
shortwave trough will eventually become absorbed by a larger scale
trough emerging from the northern Plains late in the short term
period. However, the leading shortwave trough may get close enough
to our region on Monday afternoon to bring an increase in PoPs from
west to east through the day, as the GFS suggests. The ECMWF,
however, is slower with the arrival of the leading trough and thus,
holds off on most of the precip towards mainly the long term period.
For now, went with a consenus blend of models which does support
slight/chance PoPs across the region Monday afternoon into the
evening.

&&

.LONG TERM /MONDAY NIGHT THROUGH THURSDAY/...
As of 313 PM Friday...

By Monday night, the aforementioned main trough axis will extend
from the Canadian Prairies southeastward into the Ohio Valley,
pushing a cold front through our region on Tuesday. This will bring
widespread showers and thunderstorms throughout the area on Tuesday.
With models projecting PWATs around 1.50-1.75 inches, heavy
downpours will be possible. There also will be some modest shear,
with models at this distance suggesting around 30 kts in the 0-6 km
layer. However, instability will be in question given the abundant
cloud cover that is expected.

Precipitation will end from west to east throughout the day on
Wednesday, with high pressure building in across the Ohio Valley.
This feature should then be in control through the remainder of the
week, keeping conditions mainly dry and seasonal through the end of
the long term period.

&&

.AVIATION /07Z FRIDAY THROUGH TUESDAY/...
As of 140 AM Friday...

Expecting shower development to be on the increase over the next
6 hours, and limit the activity to only showers without thunder.
The visibilities should not get worse than MVFR in shower
activity, but do expect a gradual lowering of the ceilings to
MVFR or possible IFR through 14Z. Not all terminals will see the
IFR ceilings.

Cold front sinks southward, and areas north of the boundary
will dry out in the lower levels Friday. EKN/BKW/mountains are
the last locations to return to VFR prevailing conditions.

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

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Timing of ceilings lowering could vary.
Brief IFR visibilities possible in heavy rain.

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 08/23/19
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    H    H    M    M    M    M    H    M    H    H
HTS CONSISTENCY  H    M    L    L    M    M    L    H    L    L    H    H
BKW CONSISTENCY  H    H    H    H    M    L    L    M    H    H    H    H
EKN CONSISTENCY  H    M    L    L    M    M    M    M    H    L    H    M
PKB CONSISTENCY  H    H    H    H    M    L    H    H    H    H    H    H
CKB CONSISTENCY  H    H    H    H    H    H    M    H    M    H    H    H

AFTER 06Z SATURDAY...
IFR fog possible early Saturday morning.

&&

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

&&

$$
SYNOPSIS...26/RG
NEAR TERM...26
SHORT TERM...RG
LONG TERM...RG
AVIATION...26