Scientific Forecaster Discussion
fxus61 krlx 200003
Area forecast discussion
National Weather Service Charleston WV
703 PM EST Tue Nov 19 2019
high pressure Wednesday into Thursday. Next storm system Friday
and Saturday with rain and possibly some brief snow. Cooler
over the weekend.
Near term /through Wednesday/...
as of 600 PM Tuesday...
The forecast still remains on track and only touched up on sky
condition by using the latest model guidance for a fresh update
through the rest of this period.
As of 1235 PM Tuesday...
Messy vorticity advecting east in the mid level flow this
afternoon will be overtaken by a primary vorticity lobe this
evening. This main area of vorticity advection combined with a
weak low level boundary should result in minimal chances of some
patchy drizzle or light rain early this evening (primarily
across far S/SW WV and SW va). Overnight, some modest upslope
flow along the mountains should lead to additional areas of
light rain/drizzle/fog. Light freezing drizzle may occur in the
highest elevations, resulting in a few patches of light glaze
on area roadways. However, impacts are currently expected to be
During the day Wednesday, mid/upper level troughing shifts east
with ridging then building into the area. Some clearing should
occur in the afternoon, but it will likely take awhile for
skies to clear out during the day.
Lows tonight should be similar to this morning's values as
renewed cloud cover should prevent temps from falling too much.
Although a light northwest flow late in the night could help nudge
temps a little lower. Highs on Wed will also be similar to
today's and dependent on how much clearing ends up occurring.
Short term /Wednesday night through Friday night/...
as of 138 PM Tuesday...
Mid/upper level ridging prevails Wednesday night and gradually
flattens during the day Thursday. A couple of potent vort maxes
in the 500 mb flow should advect east across the area during the
day Thursday. However, moisture availability will be greatly
limited and for now have opted to keep Thursday rather dry (and
pleasantly milder). Moisture then comes pouring back into the
region by late Thursday night and Friday. Guidance suites want
to stall a surface front near the County Warning Area on Friday, resulting in a
rather wet day (potentially). Ultimate placement in the surface
boundary will determine how wet or dry the day actually
Long term /Saturday through Tuesday/...
as of 145 PM Tuesday...
Most guidance suites want to develop an area of low pressure
late this week across the lower MS River Valley and ride it NE
along the aforementioned surface front. This should result in
another round of rain for Friday night into Saturday as the area
low pressure moves near the region. Depending on how far
south/east the boundary is located early Saturday morning, the
precip could start off as light snow before switching over to
all rain. Cold air advection should then kick in during the
afternoon which much cooler conditions expected over the
weekend. High pressure then prevails for early next work week.
Aviation /00z Wednesday through Sunday/...
as of 650 PM Tuesday...
Currently MVFR or better prevails with possible periods of IFR
in the northeast mountains near ckb/ekn. Some low stratus
fractus (700-1000ft) may impede some terminals, however am
confident that cigs will not go IFR in The Lowlands. Cigs are
forecast to lift overnight to mostly VFR (except for the
northeast mts.) With light flow in the boundary layer. For the
morning, high pressure builds in behind the trough through the
period. For the afternoon, expect mostly MVFR or better as lower
clouds try and make a comeback. Also, there will be low level
moisture left behind plaguing the mountains with lower cigs near
IFR with isolated rain/drizzle (possible freezing drizzle/snow
in the highest elevations) through the afternoon. Winds will
pick back up late afternoon (5-10kt) out of the northwest
courtesy of ridging at the surface and low pressure to the east.
Forecast confidence and alternate scenarios through 00z Thursday...
Forecast confidence: medium.
Alternate scenarios: MVFR cloud deck may become more widespread
overnight than what is currently anticipated.
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 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 Thursday...
IFR possible Friday and Friday night in rain.