Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Charleston WV
635 am EDT Wednesday may 6 2015
frontal boundary remains north of the area. Middle and upper ridge
holds in place with weak steering flow. Above normal temperatures
and mainly dry conditions prevail.
Near term /through tonight/...
6 am update. A bit more early morning River Valley fog...
otherwise no changes.
very little change to the synoptic pattern...the front remaining
far enough to the north with no direct effect on our weather.
Upper/surface ridge with weak flow holds over the area through
tonight...with thermal and moisture profiles not much different
from yesterday. Thus...the only real changes in the forecast from
yesterday would be rather minor. One change would be a slightly
better chance for a late afternoon and evening shower or storm in
the mountains. This is due to a bit more low level
convergence...as surface high pressure ridging down the Middle
Atlantic States turns the low level flow to a more easterly
direction later in the afternoon. Showers should dissipate in the
evening with loss of heating. Still not enough moisture and
instability to confidently mention showers in the low
lands...except against the western slopes where the convection may
try to propagate off the mountains. Temperatures this afternoon
will be a degree or two warmer than yesterday...as sunshine
continues to modify the airmass. Tonight looks to be rather
tranquil and warm again...similar to last night.
Short term /Thursday through Friday night/...
upper ridge holds across the region through the forecast period.
Lingering moisture along with some moisture from a low pressure
system off the Carolinas will try to make it over the over the
mountains late Thursday and Friday. This will enhance the chance for
showers and thunderstorms during the peak heating of the day on both
days...especially in the mountain zones. Temperatures stay warm
Long term /Saturday through Tuesday/...
as with the short term period...no significant changes were needed
to the long term period. Moisture from low along the coast...and
slowly approaching cold front will lead to increased chances for
showers and thunderstorms Sunday through early next week...with
the cold front prognosticated to push east through the area on Tuesday.
Somewhat cooler...and less humid air expected behind the front for
Aviation /12z Wednesday through Sunday/...
12z Wednesday through 12z Thursday...
weak synoptic flow under middle and upper ridge...with not many
features to grasp/clutch and run with.
Until 16z. Patchy IFR/LIFR River Valley fog...mainly at ekn...ckb
and pkb until 13z. Otherwise...mainly scattered middle clouds.
After 16z...thanks to a bit more low level convergence in the
mountains this afternoon...expect scattered showers and possibly a
thunderstorm...mainly after 18z. Dry elsewhere. Prevailing VFR...
scattered clouds around 7000 feet above ground level low lands. Scattered-broken 4000-7000 feet
above ground level in the mountains...briefly lower in a few showers.
After 01z...generally scattered middle clouds...occasionally broken in
mountains...then MVFR/IFR River Valley fog forming major terminals
Winds will be mainly northwesterly 4 to 8 miles per hour this afternoon...
Forecast confidence and alternate scenarios through 12z Thursday...
Forecast confidence: medium.
Alternate scenarios: depending on clouds...and rain from
today...there may be more River Valley fog than forecast tonight.
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 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1hrly 07 08 09 10 11 12 13 14 15 16 17 18
crw consistency h h h h h h h h h h h h
heights consistency M M 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 l l l h h h h h h h h h
pkb consistency l h h h h h h h h h h h
ckb consistency l M h h h h h h h h h h
After 12z Thursday...
no widespread IFR conditions expected.