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-- Discussion containing changed information from previous version are highlighted. --
000
FXUS61 KRLX 281745
AFDRLX

Area Forecast Discussion
National Weather Service Charleston WV
145 PM EDT Sun May 28 2017

.SYNOPSIS...
Showers and thunderstorms today in warm sector. Cold front late
tonight, with gradual drying into Monday. Cold fronts cross
Tuesday and Wednesday. Unsettled again next weekend.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 1000 AM Sunday...

No changes this morning.

As of 315 AM Sunday...

Another unsettled day is expected across the region. Frontal
boundary, initially stalled out across CWA, is lifting back north
this morning, as low pressure moves into the Great Lakes region.
Expecting isold showers and thunderstorms this morning, particularly
across the north as boundary lifts across the area. Showers and
thunderstorms will become more widespread during the afternoon and
evening hours during peak heating, and once again, some storms could
become severe with hail and damaging wind the primary concerns, but
overall, not expecting quite the level of threat as occurred
Saturday, as dynamics and instability not projected to be as strong.
SPC has the northern 2/3 of the CWA in a slight risk, with southern
counties in a marginal. There is also quite a bit of uncertainty as
to whether or not flash flooding will be a major concern today, but
for now, have opted to keep the watch in place, and will allow
future shifts evaluate whether to drop the watch early.

Cold front will move into the region late tonight through early
Monday, with gradually drier trends towards morning behind the
front.

&&

.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
As of 530 AM Sunday...

Upper level low drifts from Lake Superior to near James Bay,
Canada, this period, establishing a long wave trough position
over the eastern United States. This allows a series of cold
fronts to drive progressively drier, cooler and more stable air
into the area so that, by Thursday morning, high pressure sits
over the area with clear, calm conditions and valley fog.

The last of the showers with the initial cold crossing first
thing Monday morning, mainly in the mountains, will be gone by
midday, save for perhaps southwest Virginia, where there may be
a brief opportunity for an early afternoon thunderstorm.

The next cold front approaches Tuesday morning and slowly
crosses Tuesday. This will limit the chance for radiative
cooling and fog Monday night, as clouds and the gradient flow
increase, along with the slight chance for showers in the
middle Ohio Valley and northern WV. The front crosses slowly
enough to allow the chance for afternoon thunderstorms Tuesday,
but limited moisture and instability should limit thunderstorm
strength and intensity, even with sufficient shear.

The same should hold, even to a greater degree, for afternoon
thunderstorms with yet another cold front crossing Wednesday.

High pressure following the Wednesday cold front builds in late,
so the chance for showers goes well into Wednesday night, with
very late clearing toward dawn Thursday.

No changes to central guidance temperatures, which trend slowly
downward through the period, except cooler still in the valleys
at the last minute Thursday morning.

&&

.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 530 AM Sunday...

Another upper level low, dumbelling around the first near James
Bay, Canada early on, sails southeastward, and then eastward
across south central and then southeast Canada this period,
maintaining the long wave trough position in the east.

The period starts dry, with a warming trend ahead of a surface
system associated with the upper level low. That system is
progged to bring showers and thunderstorms back into the area on
Friday. Models diverge in details after that, but generally
concur on another upper level low or short wave trough keeping
the baroclinic zone in or near the area, with another surface
wave crossing. This keeps the weather unsettled again next
weekend.

Central guidance temperatures excepted, which show highs
remaining near normal and lows inching above normal, although
the MEX is higher on highs, getting into the lower to mid 80s in
the lowlands, Friday and Saturday.

&&

.AVIATION /17Z SUNDAY THROUGH THURSDAY/...
As of 130 PM Sunday...

More convection expected today, with the greatest coverage over
the eastern two thirds of the area. Formation occurring over the
southern mountains which could affect the BKW area over the next
couple of hours. As typical, TSRA can bring IFR visibilities to
the terminals.

Add TSRA to the northern terminals tonight with frontal
passage.

Ceilings to IFR late tonight in the wake of the frontal passage,
slowly improving Monday.

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY...

FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Timing and development of convection this
afternoon may vary from forecast. Development of IFR or worse
conditions late tonight somewhat uncertain.

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       15   16   17   18   19   20   21   22   23   00   01   02
EDT 1HRLY       11   12   13   14   15   16   17   18   19   20   21   22
CRW CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
HTS CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M
BKW CONSISTENCY  M    H    H    H    H    H    H    H    H    H    H    M
EKN CONSISTENCY  M    M    H    H    H    H    H    H    H    H    H    M
PKB CONSISTENCY  M    M    H    H    H    H    H    H    H    H    H    M
CKB CONSISTENCY  H    H    H    H    H    H    H    H    H    H    H    M

AFTER 18Z MONDAY...
IFR possible in isolated TSRA Tuesday and Wednesday..

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Flash Flood Watch through Monday morning for WVZ005>008-
     013>020-024>034-039-040-515>526.
OH...None.
KY...Flash Flood Watch through Monday morning for KYZ102-103-105.
VA...Flash Flood Watch through Monday morning for VAZ003-004.

&&

$$
SYNOPSIS...TRM/SL
NEAR TERM...SL/26
SHORT TERM...TRM
LONG TERM...TRM
AVIATION...26