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Area forecast discussion 
National Weather Service Charleston WV
840 PM EDT Tuesday may 5 2015

Synopsis...
frontal boundary remains north of the area. Middle and upper ridge
holds in place with weak steering flow. Above normal temperatures
and mainly dry conditions prevail.

&&

Near term /through Wednesday/...
830 PM update...

No significant changes needed with the evening update.

Previous discussion below...
weak synoptic flow under middle and upper ridge...with not many
features to grasp/clutch and run with.

Narrow Cape to around 25 thousand feet developing in afternoon warm
temperatures. Will expand area of 20 probability of precipitation for convective cells
into early evening in lowlands...with chance probability of precipitation over mountain
counties. Did add some thicker fog in the mountain valleys 06z to
12z Wednesday in the central WV mountain counties...including Elkins.

With very weak steering flow on Wednesday...still favoring the
mountain counties for afternoon shower or storm. Kept maximum
temperature at or above MOS guidance.

Most forecast soundings show enough moisture lingering at 4 to 6
thousand feet above ground level that clouds could form through the late night into early
morning...making minimum temperature tougher.

Weak low level convergence may develop along the eastern slopes
Wednesday...so continue with the higher chance probability of precipitation there. The 700
mb ridge center to our east tries to give a weak east flow into SW Virginia...so
have chance probability of precipitation extending SW to our Virginia counties.

&&

Short term /Wednesday night through Friday night/...
no major changes were necessary to the short term forecast. Upper
ridge holds across eastern U.S. With increasingly
moist...warm...and unstable atmosphere. Expecting periods of
showers and thunderstorms during peak heating in the short term
period...especially across the mountainous counties. Some moisture
from cyclone along the eastern Seaboard may move spread into our
County Warning Area on Friday...leading to increased cloud cover and chances for
showers/thunderstorms.

&&

Long term /Saturday through Tuesday/...
as with the short term period...no significant changes were needed
to the long term period. Moisture from low along the coast...and
slowly approaching cold front will lead to increased chances for
showers and thunderstorms Sunday through early next week...with
the cold front prognosticated to push east through the area on Tuesday.
Somewhat cooler...and less humid air expected behind the front for
middle week.

&&

Aviation /01z Wednesday through Sunday/...
weak synoptic flow under middle and upper ridge...with not many
features to grasp/clutch and run with.

Have some thicker fog in the mountain valleys 06z to 12z
Wednesday in the central WV mountain counties...this includes ekn.

Patches of clouds at 4 to 6 thousand feet above ground level could linger through the
night...with ceilings at 3 to 6 thousand feet broken developing after 15z in
diurnal heating.

Forecast confidence and alternate scenarios through 00z Thursday...

Forecast confidence: medium.

Alternate scenarios: patches of clouds could linger longer and cause
less fog formation than forecast in mountain valleys.

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 05/06/15
UTC 1hrly 00 01 02 03 04 05 06 07 08 09 10 11
EDT 1hrly 20 21 22 23 00 01 02 03 04 05 06 07
crw consistency h h h h h h h h h h M M
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 l l l l l l
pkb consistency h h h h h h h h h h h h
ckb consistency h h h h h h M M M M M M

After 00z Thursday...
no widespread IFR conditions expected.

&&

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

&&

$$
Synopsis...ktb/sl
near term...ktb/30
short term...sl
long term...sl
aviation...ktb/30

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