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Area forecast discussion 
National Weather Service Charleston WV
631 PM EST Wednesday Feb 10 2016

Synopsis...
deep upper level trough lifts out of the area by Thursday for a
lull in the snow showers. Snow showers pick up again Friday
afternoon into Saturday as another Arctic front plows through the
area giving even colder weather.

&&

Near term /through Thursday/...
530 PM update...just minor changes made to temperatures based on
current observation and trends. Forecast remains on track and no other
changes are needed at this time.

Previous discussion...
deep upper trough and cyclonic flow of deeper wrap around
moisture finally shift east tonight and Thursday.
Thus...improving conditions from west to east will occur. Looks
like most of the accumulating snow in the low lands...outside of a
few lingering afternoon and early evening snow showers...will
taper off to flurries early this evening. Will limit additional
accumulations of snow tonight to the mountains and its western
upslope counties...ranging from 1 to 3 inches....especially in the
higher elevations. Anticipate expiring the Winter Weather
Advisory for the low lands and southwest Virginia at 6 PM this
evening. On Thursday...any lingering snow showers in the northern
mountains will end by early afternoon...with just light additional
accumulations. Even some sunshine will return to the west half of
the area by Thursday afternoon. Arctic high pressure will continue
though...with rather frigid temperatures tonight and very cold
temperatures continuing Thursday...very much below normal. Gusty
west winds tonight on the higher elevations of the northern
mountains will continue a Wind Chill Advisory there for tonight.
Otherwise...no changes to headlines.

&&

Short term /Thursday night through Saturday night/...
brief period of high pressure succumbs to an Arctic front on
Friday night. This front will bring a return to the omnipresent
snow showers that we have experienced most of this week. With
these showers expect another 2 to 4 inches depending on shower
placement and timing. Mountain locations are once again the
favored areas due to the topography enhancement.

Temperatures plummet in the wake of the front...in what likely
will be a widespread sub-zero fahrenheit event with wind chills
approaching -30 f in the mountains.

&&

Long term /Sunday through Wednesday/...
light upslope snow showers will continue through early Saturday
night in the northwesterly upslope flow...with little to no
additional accumulations expected. Some gradual clearing expected
Saturday night...as high pressure starts to build into the region.
This with Arctic air mass in place...850mb air -23c...will result in
rather cold temperatures...particularly with snowfall on the
ground...and especially in mountain valleys. Have kept low
temperatures on Sunday in the single digits to below zero. This will
likely result in wind chill advisories Saturday night/Sunday
morning...mainly across northern West Virginia and the mountainous
counties.

Focus then shifts to next week. There is a lot of uncertainty in
this period between the models...although the models themselves
appear to have a good run to run consistency. GFS indicating a
clipper system moving into the Ohio Valley Sunday night through
Monday night/early Tuesday...with light snow showers area wide...and
a Gulf low moving east along the coast...and staying well east of
the area...eventually becoming a Nor'easter. European model (ecmwf) however indicates
a stronger southern stream solution...with low moving northeast out
of the Gulf region into the Appalachians. This would result in more
of a wintry mix scenario to start early next week...eventually
transitioning to snow on the back side of the low as it moves into
New England. For now...in coordination with other offices...did a
general broad brush of probability of precipitation in the extended...with periods of a
rain/snow mix at times across much of The Lowlands.

&&

Aviation /00z Wednesday through Monday/...
snow showers are decreasing in coverage this evening and will
eventually just taper off to flurries from west to east into
early Thursday morning. VFR conditions are already working into
the Ohio Valley this evening and heights looks like they will remain
VFR for the period. All other locations will see MVFR conditions
overnight...eventually improving to VFR from west to east through
tomorrow.

Some heavier snow showers with MVFR to brief periods of IFR
conditions should continue in mountains. Gusty west winds will
also continue along ridge tops with diminishing winds elsewhere.
By tomorrow afternoon the upper level trough will be out of the
region and even mountain locations should return to VFR.

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

Forecast confidence...medium

Alternate scenarios: ending of snow showers and flurries...along
with improving conditions...may be slower or possibly even a bit
faster than forecast.

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
EST 1hrly 17 18 19 20 21 22 23 00 01 02 03 04
crw consistency M M M M M M M M M M M M
heights consistency M M M M M M M M M h h h
bkw consistency M M M M M M M M M M M M
ekn consistency M M M M M M M M M M M M
pkb consistency M M M M M M M M M h h h
ckb consistency M M M M M M M M M M M M

After 00z Friday...
our next system arrives on Friday and IFR conditions in snow
showers will be possible again Friday night through Saturday
night...especially in the mountains.

&&

Rlx watches/warnings/advisories...
WV...Winter Weather Advisory until 6 am EST Thursday for wvz037>040.
Winter Weather Advisory until 6 PM EST Thursday for wvz046-047.
Wind Chill Advisory from midnight tonight to 10 am EST
Thursday for wvz046-047.
Ohio...none.
Kentucky...none.
Virginia...none.

&&

$$
Synopsis...arj/jmv/sl
near term...jmv/mpk
short term...jw
long term...sl
aviation...mpk

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