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000
FXUS61 KRLX 220700
AFDRLX

Area Forecast Discussion
National Weather Service Charleston WV
300 AM EDT Sat Sep 22 2018

.SYNOPSIS...
A cold front will stall to the south of the area on Saturday.
This front should lift north as a warm front on Monday night.
Another cold front moves in mid- week.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 210 AM Saturday...

Cold frontal boundary at 06Z appears to be just to the east of
the Ohio River, with continued shower activity out ahead of the
front this evening. Front will continue to sag south across the
CWA today, possibly briefly stalling out across extreme
southern/eastern zones, before continuing south of the CWA by
late this afternoon or evening. Overall, should be somewhat dry
across much of the CWA today, with best chances for any
precipitation across extreme southern/eastern zones closer to
the front.

Behind the front, lower dew points will filter into the region,
particularly north of the Ohio River, where dew points in the
50s are already starting to filter in.

Models disagree a bit tonight on the timing of the return and
placement of precipitation late tonight and early Sunday as a
wave moves into the region. Latest run of the NAM has not only
delayed onset, but coverage and amounts also, and blend of
models tends to favor this, with greater precipitation coverage
and amounts expected during the day Sunday.

&&

.SHORT TERM /SUNDAY THROUGH TUESDAY/...
As of 300 AM Saturday...

Stationary front will be located to our south at the beginning
of the period with a surface ridge extending from eastern Canada
southward across Pennsylvania into the Carolinas. A ne-sw
oriented inverted trough will be in place across the forecast
area.

Models suggest that unsettled weather is anticipated early in
the period. However, the inverted trough is expected to weaken
with time resulting in southeasterly downslope winds and
decreasing precipitation chances Monday night.

A cold front and upper level shortwave will begin to approach
the region on Tuesday resulting in precipitation chances once
again increasing from the west.

Latest temperature guidance suggest that clouds and
precipitation early in the period will result in cool daytime
temperatures. With southerly flow developing ahead of the front,
daytime temperatures on Tuesday should be above normal.

&&

.LONG TERM /TUESDAY NIGHT THROUGH FRIDAY/...
As of 300 AM Saturday...

The cold front is then expected to push southeast across the
area on Wednesday and Wednesday night with another front
pushing through on Friday.

Expect most, if not all, of the region will see showers and
thunderstorms ahead of the initial front. In addition, PWAT
values should approach 2 inches suggesting any of the showers
and storms could become capable of producing very heavy rain.
Will have to monitor the region for possible water issues.

Scattered showers are also possible ahead of the second cold
front. Long range models suggest there may be enough instability
for thunderstorms to develop on Thursday and Friday. However,
have backed off on thunderstorm chances as the airmass should be
quite cool.

Temperatures should be near normal through the period.

&&

.AVIATION /07Z SATURDAY THROUGH WEDNESDAY/...
As of 120 AM Saturday...

A cold front, and associated showers will continue to sag south
throughout the night. Brief MVFR conditions are possible with
any passing shower. Otherwise, still looking at the possibility
of local MVFR and isolated IFR stratus and fog late tonight,
particularly after 09Z. Mountainous locations are most likely to
see these conditions.  Some gradual improvement to MVFR/VFR
after 14-18Z.

Saturday, showers and thunderstorms possible
again, mainly across southern West Virginia and southwest VA,
with brief MVFR/IFR conditions.

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

FORECAST CONFIDENCE: Medium

ALTERNATE SCENARIOS: Low MVFR to IFR ceilings overnight tonight
may vary, and may linger longer than currently 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.


AFTER 06Z SUNDAY...
IFR at times in showers and thunderstorms in the central
Appalachians Saturday evening through Sunday night, and then in
the middle Ohio Valley and central Appalachians into the early
part of the next work week.

&&

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

&&

$$
SYNOPSIS...JSH/SL
NEAR TERM...SL
SHORT TERM...JSH
LONG TERM...JSH
AVIATION...SL