Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Charleston WV
422 am EDT sun Jul 31 2016
an upper level trough crosses West Virginia today, followed by a
weaker one tonight. Drier with upper level ridging into midweek.
Near term /through tonight/...
very warm and muggy air remains in place. A weak upper level short
wave trough, already bringing patchy cloud and an isolated shower
here and there early this morning, will bring about the chance for
showers and thunderstorms today, mainly east of the Ohio River. The
timing of the short wave suggests an early uptick and downturn in
convection today, with a minimal if any chance tonight.
Mid level clouds are less likely to inhibit or interrupt valley fog
Temperatures close to previous forecast, latest guidance and
Short term /Monday through Wednesday night/...
looks like a fairly quiet short term period. Have some low end pops
Monday in the lingering low level moisture behind a departing
surface front. Upper ridging should provide a dry forecast Monday
night through Tuesday night. Upper level shortwave trough crests the
ridge and heads our way Wednesday into Wednesday night. Kept pops
pretty low -- mainly slight chance -- with fairly limited moisture.
Used a consensus and European model (ecmwf) MOS blend for temperatures, which
resulted in only minor changes to previous forecast. High and lows
running near to just above normal through the period.
Long term /Thursday through Saturday/...
models have a disturbance pushing southeast into Thursday. There may
be other weak disturbances that the models are not picking up yet.
So could also be some storms during the overnight periods.
A cold front will approach from the northwest late Friday before
pushing into the area on Saturday. Wpc indicates the front should
push across the area late Saturday. This feature should result in
higher chances of showers and storms for Friday and Saturday.
Currently have high chance pops for Saturday. However would not be
surprised to see likely pops in the forecast as the time
Wpc temperatures look good and were generally used.
Aviation /08z Sunday through Thursday/...
patchy middeck overnight is again keeping lower stratus and fog
variable but all sites except bkw are likely to have IFR
conditions at some point before dawn.
The patchy middeck is associated with a weak upper level short
wave trough, which will also bring scattered showers and
thunderstorms to southwest Virginia, southern WV and the WV
mountians early Sunday morning into midday. However, there is the
slight chance for a shower or thunderstorm anywhere at anytime
Patchy fog may start to form again toward 06z Monday.
Light southwest flow continues surface and aloft.
Confidence and alternate scenarios...
Forecast confidence and alternate scenarios through 06z Monday...
Forecast confidence: medium
Alternate scenarios: timing of fog and low cloud formation overnight
into Sunday morning depends upon higher clouds and precipitation.
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 sun 07/31/16
UTC 1hrly 08 09 10 11 12 13 14 15 16 17 18 19
EDT 1hrly 04 05 06 07 08 09 10 11 12 13 14 15
crw consistency l l l l l M M h h h h h
heights consistency M l l l l M M M h h h h
bkw consistency h h M M M h h h h h h h
ekn consistency l l l l l l M h h h h h
pkb consistency l l l l l M M h h h h h
ckb consistency M M l l l M h h h h h h
After 06z Monday...
IFR conditions possible in fog during the overnight into the
morning hours each day.