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Area forecast discussion 
National Weather Service Charleston WV
316 am EDT Tuesday Aug 4 2015

Synopsis...
a cold front crosses this morning. High pressure crosses Tuesday
afternoon into Wednesday. A low pressure system crosses Thursday
and Thursday night.

&&

Near term /through tonight/...
cold front still northwest of the area early this morning will cross the
area this morning...mainly during the daylight morning hours.
Convection may refire S this afternoon depending upon the
progress of the front...but not sure about convection nam12 is
hinting at tonight S.

Otherwise morning stratocu will mix out by midday or early
afternoon. River Valley fog is possible tonight...but may be
limited across large portions of the middle Ohio Valley and
central WV...where the rain did not hit.

Blended in the mav and only some met for highs today...thought
the met was too high. Blended in bias corrected versions of the
met and mav for lows tonight which shows a slightly tighter
temperature gradient in the baroclinic zone north of the front.

&&

Short term /Wednesday through Thursday night/...
models continue to differ with the handling of the system in the
Thursday/Friday time frame. Period will start out dry...and
slightly cooler...as high pressure builds in from the north.
However...this will change by Wednesday evening...as warm frontal
boundary will lift north across the region...as low pressure moves
east towards the area. Good southwesterly flow will develop across
the area as the frontal boundary lifts north...aiding moisture
transport to the region. Precipitable water values are prognosticated to rise to around
1.6 to 1.7. Heavy rain will be a possibility during the
period...but with recent dry weather...and the fact we are in full
Summer foliage...at this point...not overly concerned about water
issues. However...this will be a good soaker of a rain...with over
an inch possibly up to 2 inches of quantitative precipitation forecast not out of the question by
Friday morning.

&&

Long term /Friday through Monday/...
next system move from the Mississippi Valley and into our region
Thursday through Friday timeframe. Warm front over the region will
lift northward as center of low and its trailing cold front is
forecast to move across Thursday night and exit Friday night.
Moisture feed is good with this storm and introduced likely probability of precipitation
across the County Warning Area by Thursday evening for showers and thunderstorms.

High pressure builds in behind the low and cold front drying US
out for the weekend with slightly cooler temperatures.

Another system affects the area late Monday with temperatures
warming a tad.

&&

Aviation /07z Tuesday through Saturday/...
line of showers and strong thunderstorms over northestern WV well S of a
cold front...were moving east-northeastward...the tail end of the line already
NE of ekn. Stronger thunderstorms are not likely to directly
effect ekn early this morning unless the line back builds more
than expected. Otherwise another cluster of showers and
thunderstorms was dissipating over the tug Fork and southern Coal
fields.

The cold front will cross the area today...reaching the Ohio
River by dawn...central WV by middle morning before crossing the
mountains by early this afternoon. Some MVFR stratocu and mist
may briefly lower to IFR around and just after dawn.

Scattered convection will fire up over the southern mountains this
afternoon as the front crosses that area. This may extend back
intothe tug Fork area depending upon the progress of the front
down there. VFR conditions coded at the six taf sites this
afternoon as convection will be too widely scattered to code...and
actually S of all sites but bkw.

Fog may start to form by 06z tonight as weak high pressure builds
into the area.

Light SW surface flow early this morning will become light northwest behind
the front today...and then light and variable to calm tonight.
Moderate west flow aloft early this morning will become light today
and remain light west Tuesday nt.

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

Forecast confidence: medium.

Alternate scenarios: development and extent of lower ceilings near
the front...may vary from forecast and be dependent on new
development of showers early this morning. This may also affect
extent of lower stratocu and mist this morning.

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 Tuesday 08/04/15
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 M M M M M M l M M M M M
heights consistency M M M M M M l M M M M h
bkw consistency M M M M M M M M M M M M
ekn consistency M M M M M M l M M M M h
pkb consistency M M h h h h M M h h h h
ckb consistency M M M M M M M M M h h h

After 06z Wednesday...
IFR possible Thursday and Thursday night in showers and
thunderstorms.

&&

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

&&

$$
Synopsis...js/arj/trm
near term...trm
short term...sl
long term...js/26
aviation...trm

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