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Area forecast discussion 
National Weather Service Charleston WV
1004 am EDT Thursday Sep 18 2014

Synopsis...
high pressure...centered to our north...moving off northeast coast
Friday. Cold front around late Sunday into Sunday night..

&&

Near term /through tonight/...
update...
no changes this morning to the forecast. Awaiting the dissolution
of the fog once again in the central West Virginia lowland
valleys.

Previous discussion...
low stratus and areas of dense fog will gradually lift around 14z
at most places. High pressure centered to our north will provide
mostly sunny skies by middle to late morning into the afternoon
hours. Temperatures will be couple of degrees warmer than
yesterdays reaching near normal temperatures for this time of the
year. Dry conditions will prevail through the period.

&&

Short term /Friday through Sunday/...
quiet pattern will continue in the short term. Broad upper troughing
over the northeast Continental U.S. Friday will gradually break down with zonal
flow Saturday as another upper trough moves eastward across the
upper Midwest into the Great Lakes. No major changes from previous forecast
with latest data. Surface high pressure centered to the north at the
outset of the period continues to shift eastward off the New England
coast by 00z Sat with resultant bl winds setting up out of the
southeast. Low level moisture will bank up against the eastern mountains
and have continued a slight chance of showers in that general area
as such...again which previous forecast had a good handle on. Latest nam12
moisture profiles hint at some potential for convective showers
further west over the central WV lowlands but at this
point...moisture availability at around the 850mb-800mb level may be
somewhat overdone as well as the Colorado-located instability. Thus for
now...left the forecast dry for all of The Lowlands. Maximum temperatures
generally upper 70s lowlands still look good.

Dry weather under mostly sunny/clear to partly cloudy skies will
continue Friday night and Saturday with less low level moisture
available. Only change of any real significance was to ramp up
temperatures on Saturday by a good 3-5 degrees for much of The Lowlands.
Temperatures at 925mb prognosticated around 20c-22c should result in low 80s for
many locations...a trend which is also bearing out in latest MOS
guidance. Temperatures will be slightly warmer Sat night versus Friday night
with south/southwest winds and increasing clouds with an approaching
cold front moving into the lower Great Lakes region by 12z sun.

&&

Long term /Sunday night through Wednesday/...
used wpc thinking with some minor tweaks. Cold front will push
southeast of the mountains Sunday night with high pressure taking
control by Monday afternoon. The high should be in control through
the remainder of the period...resulting in dry and seasonably cool
temperatures.

Wpc temperatures looked good and were generally used.

&&

Aviation /14z Thursday through Monday/...
areas of IFR low stratus and radiation fog will gradually
dissipate by 13-14z lifting to a low cloud deck until middle to late
morning.

VFR conditions will prevail today and most part of tonight.
Another night of radiation fog and low stratus can be expected
although conditions could develop a bit later than compared with
last night.

The NAM model show a weak middle level disturbance crossing around
18-21z. With lingering low level moisture...expect some middle cloud
formations Thursday afternoon and evening. So another cloud versus
fog issue overnight Thursday. Could not even completely rule out a
few patches of light rain 06z to 12z in the south or mountain with
weaker middle level disturbances and the turning of southeast flow
late Thursday.

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

Forecast confidence: high.

Alternate scenarios: clouds may linger longer than expected today.

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 14 15 16 17 18 19 20 21 22 23 00 01
EDT 1hrly 10 11 12 13 14 15 16 17 18 19 20 21
crw consistency M M h h h h h h h h h h
heights consistency M 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 h h h h h h h h h h
pkb consistency M h h h h h h h h h h h
ckb consistency M h h h h h h h h h h h

After 12z Friday...
IFR River Valley fog expected early Friday.

&&

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

&&

$$
Synopsis...arj/50
near term...arj/26
short term...50
long term...jsh
aviation...jsh

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