Scientific Forecaster Discussion
Area forecast discussion
National Weather Service Charleston WV
603 am EDT Monday Aug 31 2015
fairly humid weak ahead...but with upper ridge and lack of
organized surface features only isolated to scattered
showers/storms expected with diurnal trend.
Near term /through tonight/...
models show an 500 mb short wave evident in vorticity charts over
western NC...eastern Kentucky and southwest Virginia moving north northeast
today. This system is producing extensive upper to middle level
clouds across the region. Radar images show areas of light rain
showers moving across the Appalachians from east to west. Went
with low chance probability of precipitation over the mountains and western slopes through
Another middle level disturbance is evident over the Ohio Valley.
Models indicate that this system will remain stationary there. It
is still uncertain if this system will impact the local weather.
Drier weather conditions are expected tonight with rainfall
activity decreasing and exiting the Easter mountains.
For temperatures...went with the super blend...generally in the
middle 80s lowlands ranging to the middle 70s highest elevations. Lows
are expected to in the middle 60s due to moisture available and
Short term /Tuesday through Thursday night/...
in between systems with a very summerlike weather pattern this
period with a weak upper ridge dominating the area. Even with a
moist atmosphere in place...the upper ridge and lack of any
surface boundaries will tend to suppress organized convection.
Convection will be scattered at best...associated with diurnal
heating...especially over the mountains where an elevated heat
source is present. However...most areas will likely remain dry
this period. Temperatures and humidities will be on the
increase...with highs reaching near 90 degrees by Wednesday.
Long term /Friday through Sunday/...
with a weak steering flow and no fronts in our vicinity...the long
term will continue the Summer time pattern...despite the approach
of the Labor Day weekend.
Will type to have mostly a diurnal shower/storm possibility with
20/30 probability of precipitation most days. Of course...as we get closer...there will
probably be a day...where we can enhance or decrease those probability of precipitation.
A better chance of southeast flow Saturday...so slightly higher probability of precipitation
over the mountain counties compared to further west..for Saturday
Figuring a relatively dry ground...will try to have maximum
temperatures at or above GFS MOS guidance in The Lowlands.
Aviation /10z Monday through Friday/...
upper level wave moving will continue to move north from
northeast Kentucky and southwest Virginia into WV today. Satellite images and
surface observation show broken to overcast 12kft ceilings across most sites.
Areas of clearing could spread from west to east for VFR
conditions to prevail today.
An isolated shower possible along the eastern mountains and
across the extreme southern WV...rainfall should be very light.
Flow will remain light and variable or calm at most sites.
Better chances for showers or storms exist along the eastern
mountains during the afternoon hours. However...VFR conditions
River Valley fog expected overnight tonight under clear skies and
Forecast confidence and alternate scenarios through 06z Tuesday...
Forecast confidence: medium.
Alternate scenarios: River Valley fog may form tonight if breaks
in clouds develop. Any shower could produce MVFR conditions if
moves through a taf site.
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 Monday 08/31/15
UTC 1hrly 09 10 11 12 13 14 15 16 17 18 19 20
EDT 1hrly 05 06 07 08 09 10 11 12 13 14 15 16
crw consistency l l M 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 M M M 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 06z Tuesday...
spotty IFR possible in dense valley fog during early mornings...mainly
in WV and highly dependent on cloud cover.