Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Charleston WV
1235 am EST Sat Dec 20 2014
persistent clouds through tonight. A weak disturbance passes south
Saturday. Dry Sunday. System may clip mountains Monday.
Near term /through today/...
915 PM update...made some minor tweaks to temperatures based on current
models and soundings continued to Show Low level moisture
persisting into the evening hours along with the stratocu. Some
drying...eroding clouds and clearing skies taking place especially
along our southern border zones and into the Greenbrier valley.
This clearing won't last long as satellite pics showing high to
middle clouds increasing from the SW. These clouds will continue to
increase from the SW overnight as weak low pressure system tracks
to our south. Some moisture from this system will brush the
extreme southern areas of the County Warning Area towards daybreak. Temperatures are expected to
drop below freezing overnight and a brief period of light snow is
possible before mixing with and changing to rain towards the late
morning hours Saturday. This system quickly exits and any
precipitation will quickly end by Saturday afternoon. Temperatures are a blend
of current grids and guidance.
Short term /tonight through Monday night/...
a wave leaving a slight chance of rain still possible in the
southwest portions of West Virginia late Sunday afternoon and evening. By
Monday morning...high pressure will dominate leaving dry weather and
clearing skies. The high will push east overnight Monday as another
system skirts our eastern and southern West Virginia counties. This
will introduce another chance of rain...with some light snow
possible around the Monday morning commute times. With fairly warm
ground and a quick warm up as the sun rises...little to no
accumulation is expected.
High temperatures will be on the rise Sunday and Monday...eventually
reaching into the 50s for The Lowlands.
Long term /Tuesday through Friday/...
active weather pattern continues in the long term period. Still a
chance for some light precipitation Monday night/ Tuesday as low
pressure moves northeast along the coast. Expecting precipitation to
mostly be in the form of rain...except across the mountains there
-sn or a -rasn will be observed. At this point...impacts for this
event look minimal.
Focus then shifts to an upper low across the Midwest...with surface
low pressure and associated cold front Tuesday night into Wednesday.
Out ahead of the front...moisture and temperatures will be on the
increase...with precipitable water values prognosticated to rise over an inch...and
temperatures expected to be warm enough everywhere for precipitation
to initially fall as rain. This will change however on
Wednesday...as a cold front moves through the area Tuesday
night/early Wednesday...with temperatures falling behind the front
on Wednesday...gradually changing any lingering precipitation to
snow County Warning Area wide. In addition to the snow...winds will pick up along
and Post frontal passage. Also...a rumble of thunder cant be ruled
out during this period with the frontal passage.
This remains a tricky system to forecast in terms of overall
impacts...as ground temperatures may at least initially remain warm
enough...particularly across lowlands...to limit snowfall
accumulations. Have however decided to go ahead and highlight the
storm in the severe weather potential statement...since it will affect the area Christmas evening into
Christmas. Speaking of Christmas day...area will be under the
influence of the upper low for at least the first part of the
day...with periods of -shsn.
Aviation /06z Saturday through Wednesday/...
stratus deck should gradually lift northwestward overnight...but may
remain in Ohio today. A low pressure system moving well south of the
region will provide some clouds today and possibly some
precipitation...mainly in Virginia and southeastern WV. Some MVFR cloud
restrictions are also possible in Virginia and southeastern WV. As the
system moves away...the stratus deck is expected to build back
southeastward over much of the area Saturday night.
Forecast confidence and alternate scenarios through 06z Sunday...
Forecast confidence: low on the timing and placement of the stratus
Alternate scenarios: timing of the stratus deck moving northwestward
could change considerably. Timing of the stratus deck returning
Saturday night could vary.
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.
Date Sat 12/20/14
UTC 1hrly 06 07 08 09 10 11 12 13 14 15 16 17
EST 1hrly 01 02 03 04 05 06 07 08 09 10 11 12
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 l h h h h h h h M M 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 06z Sunday...
IFR possible in mountains Sunday night Monday with a wintry mix.
IFR possible in rain changing to snow Tuesday night into Wednesday.