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fxus61 krlx 232326 
afdrlx

Area forecast discussion
National Weather Service Charleston WV
726 PM EDT Wed Oct 23 2019

Synopsis...
high pressure through Thursday night yielding dry conditions
and seasonable temperatures. A system will begin to affect the
area Saturday with increasing rain through the day into Sunday.

&&

Near term /through Thursday/...
as of 720 PM Wednesday...

Blended locally produced co-op MOS into lows tonight, which
resulted in a bit cooler forecast for sheltered valleys. This
seems like the right trend with dew points currently in the 20s
and low 30s. Opted to expand frost advisory west another tier
or two of counties.

As of 130 PM Wednesday...

With clear skies and valley winds expected to become light
tonight in portions of West Virginia and southwestern Virginia,
expect frost to form. Will issue a frost advisory for valleys in
these areas. Note that due to previous freezing temperatures,
the growing season has ended already in much of the West
Virginia mountains, so no frost advisory in those areas.

A high pressure system will slide eastward as a weak and dry
cold front approaches from the northwest. This front will stall
over central Ohio Thursday, providing only some clouds in Ohio
and northwestern West Virginia.

&&

Short term /Thursday night through Saturday night/...
as of 240 PM Wednesday...

During this period a southern stream trough will inch towards
the area along with southwesterly strong flow advecting
moisture as well. With clouds advecting in, temperatures will
not get that optimal radiational cooling for frost, however
frost potential will remain in the far northeastern mountains.
This trough will promote chances of showers as early as Friday
afternoon mainly confined to the southern edge of the County Warning Area.
Models are now in very strong agreement on starting time for the
rain around late Saturday morning spreading from south to
north. Saturday afternoon is when the models come into even better
agreement and most are in line with having rain accumulations
spread areawide around 1 to 1.5 inches total, for that reason
left in likely rain into Sunday. Another surface low and upper
level trough is expected to form to the far northwest which
will help push our system out quicker sometime around Sunday
morning.

Accepted temperatures from guidance as they will hover around
seasonable for this period.

&&

Long term /Sunday through Wednesday/...
as of 240 PM Wednesday...

High pressure will set in during this period, however an active
weather pattern will exist regionwide with a very broad
elongated trough from Canada associated with an upper level
closed expected to move through the area. This feature may spawn
a few surface lows during the beginning of the work week into
Wednesday which has potential to increase rain chances and cause
much, much cooler temperatures. Models are too far in
disagreement therefore went with central guidance and left in
chance pops through the rest of this period.

Accepted temperatures from guidance although these will most
likely have to be tweaked later on as models come into better
agreement.

&&

Aviation /00z Thursday through Monday/...
as of 720 PM Wednesday...

VFR conditions expected through the forecast period with just
some passing high clouds across the west and north. Generally
calm winds tonight will become light out of the south to
southwest Thursday afternoon.

Forecast confidence and alternate scenarios through 00z Friday...

Forecast confidence: high.

Alternate scenarios: none.

Experimental table of flight category objectively shows consistency
of weather forecast office 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 22 23 00 01 02 03 04 05 06 07 08 09
EDT 1hrly 18 19 20 21 22 23 00 01 02 03 04 05
crw consistency h h h h h h h h h h h h
heights consistency h h h h h h h h h h h h
bkw consistency h h h h h h h h h h h h
ekn consistency h h h h h h h h h h h h
pkb consistency h h h h h h h h h h h h
ckb consistency h h h h h h h h h h h h

After 00z Friday...
morning valley fog possible Friday particularly in deeper
mountain valleys.

&&

Rlx watches/warnings/advisories...
WV...frost advisory from midnight tonight to 9 am EDT Thursday for
wvz005>011-013>020-024>034-039-040.
Ohio...none.
Kentucky...frost advisory from midnight tonight to 9 am EDT Thursday for
kyz105.
Virginia...frost advisory from midnight tonight to 9 am EDT Thursday for
vaz003-004.

&&

$$
Synopsis...rpy/arj

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