321
FXUS61 KRLX 200517
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
117 AM EDT Mon May 20 2024

.SYNOPSIS...
A high pressure system will provide hot and dry weather into
midweek. A cold front brings showers and thunderstorms late
Wednesday and Thursday. Cooler Thursday and Friday.

&&

.NEAR TERM /THROUGH TODAY/...
As of 1050 PM Sunday...

Trended overnight temperatures generally a degree or two cooler
given afternoon mixing with drier air aloft, which has allowed
temperatures to quickly tumble this evening amid clear skies and
very light SFC-H850 flow. River valley fog develops throughout
the night, along with a bit of stratus along the eastern slopes
of portions of the mountains. The rest of the forecast remains
on track.

As of 750 PM Sunday...

Made minor modifications to cloud cover through Monday to
represent the latest trends, but otherwise, the forecast remains
on track. Diurnally driven Cu field has quickly dissipated
across much of the region, with portions of the mountains being
the one exception. Lingering surface convergence courtesy of
anabatic flow could squeeze out a highly isolated light shower
across the northeast mountains over the next hour or so, but
most, if not all areas will remain dry, as katabatic flow begins
in ernest after sunset and ends any chance of precipitation.

As of 215 PM Sunday...

Mid-upper level high pressure provides mainly dry weather with
morning valley fog and afternoon cumulus amid above normal
temperatures, which will reach at least the mid 80s across the
lowlands this afternoon where they have not already, and then
the upper 80s across the lowlands Monday afternoon. There will
be somewhat of a ridge/valley split on lows tonight, lower 60s
hilltops and upper 50s valleys, and 50s in the mountains.

A weak surface trough along the mountains, along with the
elevated heat source effect, was providing enough focus for a
more stout cumulus field, with some of the cumulus convection
vigorous enough for a shower or even a thunderstorm. With
precipitable water values under an inch, water issues are not
anticipated. Mid-upper level ridging and less of a surface
trough, if any, should keep Monday free of showers and
thunderstorms altogether.

&&

.SHORT TERM /TONIGHT THROUGH WEDNESDAY NIGHT/...
As of 216 PM Sunday...

Drier, and increasingly warmer weather is in store for Tuesday, as
high pressure surface and aloft continues to build into the region.
Can`t completely rule out an isolated shower or storm developing
during peak heating hours Tuesday, provided something can break
through the cap, but overall, expect much of Tuesday to remain dry.
With the building ridge across the area, some locations could even
top out around 90 by Tuesday, which according to the nws heat risk
map, sensitive individuals could be affected, even though this is
below criteria for an advisory.

Low pressure will move northeast into Canada Tuesday into Wednesday,
eventually sweeping a cold front across the area on Thursday.
Showers and storms will develop out ahead of the front Wednesday
afternoon and evening, with the possibility of some storms becoming
strong to severe, mainly across parts of SE Ohio and perhaps into NE
KY, with a damaging wind threat.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 1230 PM Sunday...

Frontal boundary will move through the region Thursday, potentially
stalling out just to our south early Friday, as surface high
pressure briefly builds in across the north. Most of the CWA will
remain dry on Friday, however, isolated showers and storms will
continue to be possible across the south in particular, closer to
the front.  Active weather will return over the weekend, with the
approach of another system from the west.

&&

.AVIATION /06Z MONDAY THROUGH FRIDAY/...
As of 100 AM Monday...

VFR conditions outside of patchy river valley fog that is
likely to develop this morning as most locations across the area
have already decoupled. Restrictions will likely occur at
CKB/CRW/EKN/PKB and these restrictions will vary, but IFR/LIFR
is the most likely category, particularly for the most sheltered
valleys (i.e CRW/EKN).

Overall, fog coverage and density will be less expansive and
intense than it was last night. Any fog that develops will
lift/dissipate between ~11-1230Z this morning, with the
sheltered valleys holding it to the latter end of the range.

Widespread VFR expected today once fog lifts. Skies will be
speckled with CU fields this afternoon due to diurnal heating.
There is a chance for an isolated shower or thunderstorm across
the mountains this afternoon, but all sites in this region
look to remain out of the probability at this time.

Surface flow will remain calm through the morning. Light and
variable surface flow is expected at all sites today.

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

FORECAST CONFIDENCE: High

ALTERNATE SCENARIOS: Timing, coverage, and intensity of fog
formation tonight could vary from the 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                                             MON 05/20/24
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    M    M    M    M    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    H    M    L    H    H    H
BKW CONSISTENCY  H    H    H    H    H    H    L    L    L    H    H    H
EKN CONSISTENCY  H    H    H    L    L    M    M    M    M    M    H    H
PKB CONSISTENCY  H    H    H    H    H    H    H    M    M    H    H    H
CKB CONSISTENCY  H    H    H    H    H    L    L    L    M    H    H    H

AFTER 06Z TUESDAY...
IFR conditions possible with river valley fog or low stratus
Tuesday morning, then again with showers and thunderstorms late
Wednesday and Thursday with a cold FROPA.

&&

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

&&

$$

SYNOPSIS...TRM/SL/GW
NEAR TERM...TRM/GW
SHORT TERM...SL
LONG TERM...SL
AVIATION...LTC