Scientific Forecaster Discussion

Return to Local Conditions & Forecast

Without Abbreviations
With Abbreviations

Area forecast discussion 
National Weather Service Charleston WV
150 am EDT Wednesday Jul 27 2016

Synopsis...
a weak east to west frontal boundary will dissolve over the area
overnight and Wednesday. An upper level system will tap copious
moisture to likely produce heavy rainfall Thursday into Friday.

&&

Near term /through today/...
sent a quick update to remove all pops through at least 12z. Also
adjusted hourly temperatures to match recent obs and model
tendencies. Patchy dense fog expected to develop overnight at most
sites. Low visibilities and ceilings are possible over areas that
received rainfall and along river valleys.

&&

Short term /tonight through Friday night/...
active weather to start the short term period...with warm and humid
conditions to persist. Stalled frontal boundary across northern
zones will lift north of the area during the day Thursday as upper
shortwave trough approaches from the west. Strong llj developing
across the region...will aid in moisture transport...with pw values
rising to over 2 inches Thursday. Wave of low pressure moving north
through the region Thursday and Thursday night...will help to
enhance precipitation...with showers and thunderstorms...with heavy
downpours expected. In addition...could see strong to severe storms
during the afternoon and evening hours on Thursday...with the
potential for stronger winds aloft to be brought down to the
surface. Will place the mention of possible water headlines for the
Thursday/Thursday night time frame. Still difficult to pinpoint any
area of heaviest precipitation/greatest threat...so will highlight
entire cwa in the hwo for now.

Additional showers and thunderstorms expected for later in the day
Friday and Friday night as an upper shortwave trough crosses the
area.

&&

Long term /Saturday through Tuesday/...
weather looks to remain unsettled for the first part of the extended
period as additional disturbances move through the region. Drier
weather possible early to mid next week as upper ridging strengthens
across the region.

&&

Aviation /06z Wednesday through Sunday/...
tricky forecast overnight. With antecedent pcpn, near calm flow
and areas of clearing you can expect IFR/LIFR in dense fog right?
Well, some mid to upper clouds are evident on satellite images
moving east to affect pkb, ckb, and perhaps ekn later on. The rest
of sites could fog to LIFR ceilings. Visibilities could fluctuate
between IFR and MVFR at times. Coded IFR/LIFR conditions at most
sites except bkw which keep IFR conditions.

Surface flow will be light and variable except for strong gusts
in thunderstorms Wednesday afternoon. Flow aloft will continue
light west.

Confidence and alternate scenarios...

Forecast confidence and alternate scenarios through 06z Thursday...

Forecast confidence: medium.

Alternate scenarios: timing of fog formation and intensity may
vary overnight. A shower or thunderstorm could directly affect any
taf site Wednesday afternoon.

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 Wednesday 07/27/16
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 M h h h h
heights consistency l l l l l l l M h h h h
bkw consistency h h h h M M M h h h h h
ekn consistency l l l l l l l M h h h h
pkb consistency l l l l l l l M h h h h
ckb consistency l l l l l l l M h h h h

After 06z Thursday...
brief IFR conditions possible in thunderstorms every afternoon
and evening. Early morning IFR fog possible into mid week
depending, in part, on occurrence of showers or thunderstorms the
previous afternoon or night.

&&

Rlx watches/warnings/advisories...
WV...none.
Ohio...none.
Kentucky...none.
Virginia...none.

&&

$$
Synopsis...trm/jmv/sl
near term...arj/trm/jmv
short term...sl
long term...sl
aviation...arj

National Weather Service Glossary of Abbreviations