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fxus61 krlx 231524 

Area forecast discussion
National Weather Service Charleston WV
1024 am EST Thu Feb 23 2017

unseasonably warm today and Friday. A strong cold front crosses
pre-dawn Saturday morning, followed by cooler weather for the
weekend. A couple systems next week with precipitation chances.


Near term /through tonight/...
as of 1020 am Thursday...

Forecast on track as isolated showers move across area
associated with a weak upper level short wave trough today.

As of 230 am Thursday...

In the warm sector today with areas of morning fog. Column
humidities still have maxima meaning clouds should linger
through a good portion of the day. May even see a scattered
sprinkle or shower.

A little instability this afternoon may result in some cumulus
build up, but largely should avoid any thunder.

Clouds on the decrease tonight as drier air moves overhead as
the warm front moves well to the north.


Short term /Friday through Sunday/...
as of 310 am Thursday...

Main weather maker for the short term is a strong cold front
Friday night into Saturday. Ahead of this front, expecting
good warm air advection, with even little downsloping component by mid
afternoon as winds turn south-southeast. Mav and met running above most
other guidance, but with the extra help of the downsloping opted
to trend this way as well. Have decent chance to break at least
daily records...and possibly even some month of February

Still some timing differences between models, with European model (ecmwf) and
GFS fairly close with front crossing County Warning Area from 06z-12z Saturday.
NAM is about 3 hours slower. All models show the bulk of the
precip occurring along and behind the front, so kept a dry
forecast Friday, with pops ramping up quickly around midnight.

Around 500-700 j/kg cape with this system -- which is decent
for overnight hours in February. And with the dynamic lift from
the cold front, expecting thunderstorms overnight. Good shear
expected during the same time frame. NAM showing 40kts bulk
shear near the highest instability axis, but increasing to
60+kts just behind the best instability. This combination should
be enough to create some threat of strong to severe
thunderstorms. Best chance of strong to severe storms will be
across the mid Ohio River valley, as convection moves in from
the west...with a weakening trend as things move east across WV.

Precipitation gradually tapers off Saturday and Saturday night.
Cold enough air filtering in by late Saturday to see some snow
flakes mixing in before precip ends. Brief high pressure
expected Sunday.


Long term /Sunday night through Wednesday/...
as of 320 am Thursday...

High pressure will be drifting away to the east Sunday night
with attention turning to a potential southern stream system for
Monday. European model (ecmwf) not very excited about this, but the GFS brings a
surface wave up the Ohio River valley. Opted for chance pops
with this, hoping for better model consistency as we get closer.
A surface low comes out of The Rockies midweek, bringing
another chance of precip. Have likely pops on Wednesday as a
cold front moves through.


Aviation /16z Thursday through Monday/...
as of 610 am Thursday...

Improving conditions today as morning fog and low stratus burn
and mix out as warm front wanders further north. Stratus hovers
around the VFR/MVFR line today, but opted to keep tafs closer to

Forecast confidence and alternate scenarios through 18z Friday...

Forecast confidence: medium

Alternate scenarios: MVFR may be the better choice for low
stratus today.

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 15 16 17 18 19 20 21 22 23 00 01 02
EST 1hrly 10 11 12 13 14 15 16 17 18 19 20 21
crw consistency h h M l h h h h h h h M
heights consistency M M M h M h h h h h h M
bkw consistency l M M h h h h h h h h M
ekn consistency l l M M M M h h h h h M
pkb consistency M h M h M h M M h h h M
ckb consistency h h M M M M M M h h h M

After 18z Friday...
no widespread IFR conditions are expected at this time.


Rlx watches/warnings/advisories...



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