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Area forecast discussion 
National Weather Service Charleston WV
630 am EDT Tuesday may 5 2015

Synopsis...
frontal boundary remains north of the area. Upper ridge holds in
place. Above normal and mainly dry conditions prevail.

&&

Near term /through tonight/...
6 am update. Trimmed back probability of precipitation/thunder potential a little on
northern convection this morning...per radar/hi res model trends.

Previous discussion...
500 mb heights rise slowly this period...but so does the moisture.
While a frontal boundary stays to our north with little direct
effect from it in terms of convection...an upper disturbance will
squeeze through the building heights and move east across
central/southern Ohio and far northern West Virginia this morning.
This upper disturbance...in combination with increased moisture in
the warm sector and a leftover outflow boundary over southern Ohio
from previous convection...will likely initiate pre dawn convection.
The convection will then move across mainly the far northern
portions of our area early to middle morning with the disturbance. Will
go with high chance to likely probability of precipitation over portions of southeast Ohio
early...tapering to lower chance probability of precipitation over northern West
Virginia...as we get past the favored diurnal time for early morning
convection. Most of this convection north will be over around middle
morning. Convection thereafter with be mostly diurnally driven. The
most likely area for afternoon convection will be in the mountains
where elevated instability will be most favorable for the
convection. Otherwise...with no focusing mechanism...most of the low
lands will remain dry for this afternoon. Temperatures will be a
degree or two warmer today with a warmer start to the day...in the
lower to a few middle 80s. I

For tonight...almost like a Summer scenario. Any left over
convection will dissipate this evening with loss of heating. This
will leave a tranquil...but rather moist and quite mild night...
with mins near 60 degrees.

&&

Short term /Wednesday through Friday/...
very few changes to the short term forecast this evening with little
movement to the synoptic pattern. Upper ridge still in control...and
surface high pressure becomes a touch more dominant.
Therefore...best forcing will be from the elevated heat sources in
The Highlands of the eastern County Warning Area while the bulk of the County Warning Area remains
dry. Dewpoints will creep into the low 60s...so this will raise the
lower limit on the overnight minimum temperatures through the
period...while the increased surface drying will lead to a slow
upward trend in the afternoon highs. It is not going too far to call
this a heat wave relative to the time of year...with temperatures
that will be in the 10-15 degree above normal territory.

&&

Long term /Friday night through Monday/...
only minor adjustments made to long term period by blending in wpc
guidance. Upper ridge remains in control. Cannot rule out some
convection firing on the eastern side of the ridge...over the WV
mountains each afternoon. Cold front approaching late in the
period...which may move through Monday night or Tuesday.

&&

Aviation /12z Tuesday through Saturday/...
12z Tuesday through 12z Wednesday...
through 00z. An upper disturbance will cross the northern portion of
the area through 13z...with scattered showers and possibly a
thunderstorm. Thereafter...with east to west frontal system to our
north...any convection will be diurnal and mainly in the mountains
and far north. Given all this...any showers will mostly be high
based. So expect VFR at or above 4500 feet above ground level to prevail through the
period...except briefly lower in a few heavier showers in the
mountains.

After 00z...showers rapidly dissipate with loss of
heating...with scattered-broken clouds 7000-10000 feet above ground level.

Forecast confidence and alternate scenarios through 12z Wednesday...

Forecast confidence: high.

Alternate scenarios: if and where it rains...these may be fog
formation tonight.

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.

UTC 1hrly 11 12 13 14 15 16 17 18 19 20 21 22
EDT 1hrly 07 08 09 10 11 12 13 14 15 16 17 18
crw consistency h h h 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 h h h 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 12z Wednesday...
no widespread IFR conditions expected.

&&

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

&&

$$
Synopsis...jmv/26
near term...jmv
short term...26
long term...mz
aviation...jmv

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