Area forecast discussion
National Weather Service Charleston WV
156 am EDT Thursday Jun 20 2013
Synopsis...
high pressure and weak flow. Ridge aloft keeps mostly dry conditions
through the weekend. However...mountain convection possible Thursday
afternoon.
&&
Near term /through today/...
forecast looks representative of expected conditions. No updates
needed at this time...
Previous discussion below...
As mentioned in the aviation discussion from earlier this Wednesday
evening...was a bit faster forming the fog in the wet counties from
ckb down through crw into SW Virginia. Patches of clouds on weak east flow
may delay fog a bit in Pocahontas County.
This weak Summer wind pattern may allow for some thermals to break
through the middle level cap late Thursday over the mountainous
counties...then drift about in the evening. Will not adjust pop up
a bit yet...will have graveyard shift look at all the 00z guidance.
But was thinking in that direction currently.
No major temperature changes.
&&
Short term /tonight through Saturday/...
weak flow at all levels as we remain under control of Bermuda high
pressure to the west and very weak ridging aloft. Middle and upper
levels very dry as well...and all factors lead to a low pop
environment with above normal temperatures. Throw in some afternoon
probability of precipitation based on elevation primarily and also ability to reach the
convective temperature...but most locations should remain capped at
700mb...and thus dry as well. Showers that do form will collapse
quickly with little support in all aspects.
In the end...not a lot of changes to the previous forecast.
&&
Long term /Saturday night through Wednesday/...
surface high pressure will remain centered across the southeast
states...with a ridge extending north into West Virginia.
Southerly winds will result in dew points increasing to the upper
60s and lower 70s. As a result...isolated to scattered showers and
thunderstorm will be a possibility...mainly during the afternoon and
evening hours.
An upper level trough and an associated cold front will approach from
the west late in the period...resulting in better chances for
showers and storms. The best chance of getting wet will continue to
be during the afternoon and evening hours.
Expect daytime temperatures to generally be 5 or more degrees
above normal during the period.
&&
Aviation /06z Thursday through Monday/...
expect IFR River Valley fog and over areas that received rainfall
during the past couple of days mainly central and southern WV
overnight. The most probable sites impacted will be
crw...ekn...and bkw.
Low stratus could result across the western slopes overnight to
dissipate by sunrise. Mostly clear skies expected through at least
17z. Low level cumulus could develop with afternoon heating and
available low level moisture. However...conditions will prevail
VFR for the rest of Thursday.
Calm flow and clear skies could result in another foggy night
Thursday night into Friday morning.
The weak southeast flow could form some slow moving and mainly isolated
cells 18z Thursday to 00z Friday including the kbkw vicinity.
Confidence and alternate scenarios through 06z Wednesday...
Forecast confidence...medium.
Forecast confidence and alternate scenarios through 06z Friday...
Forecast confidence: timing of density and duration of reduced visible
and/or low stratus after 06z Thursday may 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 Thursday 06/20/13
UTC 1hrly 06 07 08 09 10 11 12 13 14 15 16 17
EDT 1hrly 02 03 04 05 06 07 08 09 10 11 12 13
crw consistency l l l l l l l l M h h h
heights consistency h h M l l l l M h h h h
bkw consistency h h h h h h h h h h h h
ekn consistency l l l l l l l l M h h h
pkb consistency h h M l l l l M h h h h
ckb consistency M l l l l l l M h h h h
After 06z Friday...
IFR/LIFR in nocturnal fog less widespread...but still possible 06z
to 12z Friday.
&&
Rlx watches/warnings/advisories...
WV...none.
Ohio...none.
Kentucky...none.
Virginia...none.
&&
$$
Synopsis...jmv/26
near term...ktb/arj
short term...26
long term...jsh
aviation...arj
