Scientific Forecaster Discussion
fxus61 krlx 170232
Area forecast discussion
National Weather Service Charleston WV
932 PM EST Sat Dec 16 2017
high pressure tonight. Weak system with chance of showers Sunday
afternoon/evening. Cold fronts cross Tuesday.
Near term /through Sunday/...
as of 930 PM Saturday...
Setting up to be a difficult forecast for the overnight lows
tonight. Have seen some areas decouple already and drop into the
20s, while other sites, especially on hills, are still in the
upper 30s to lower 40s.
As of 1220 PM Saturday...
A high pressure system will provide dry weather and light winds
tonight. However, some cirrus in advance of the next system will
be moving into the region. Think that enough good radiation
conditions will exist to go on the cooler side of MOS guidance
Flattening wave aloft moves over the area Sunday afternoon and
evening. While some showers are expected, most of the moisture
will be used trying to wet the lower levels of the atmosphere.
Therefore, precipitation amounts will remain on the lighter
Short term /Sunday night through Tuesday night/...
as of 250 PM Saturday...
Dampening S/W trof quickly exits to the east Sunday evening.
However, an abundance of low level moisture will linger along
with some weak isentropic lift in warm air advection. This was handled with
light rain and drizzle in the wx grids. There is some concern
for perhaps some freezing drizzle or light freezing rain in the
higher elevations, however confidence is not particularly high
at this point for any mention in the severe weather potential statement. All of this will try
to linger for the first half of Monday along and north of the
i64 corridor as warm air advection strengthens to our southwest. This may setup
a significant temp gradient across the area with low
stratus/drizzle across the north and some sunshine across
extreme southern counties. I have undercut guidance for highs
Monday quite a bit across the north as a result. The warm air advection
eventually wins out by Monday evening.
Long term /Wednesday through Saturday/...
as of 255 PM Saturday...
A southern system will scoot by mainly to the south Wednesday
and Thursday, though enough of a spread for some low pops across
the mountains. Attention then turns to the weekend where there
remains considerable spread on the synoptic pattern evolution
across the eastern conus, as a battle looms between building
warmth across the southern states and advancing cold air from
Aviation /02z Sunday through Thursday/...
as of 625 PM Saturday...
Increasing cloud cover expected through the period, with the
atmosphere saturating from the top down. Thus, ceilings will
gradually lower as low pressure aloft moves towards the region
from the southwest. Winds expected to stay below 10kts through
Forecast confidence and alternate scenarios through 00z Monday...
Forecast confidence: high.
Alternate scenarios: none.
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 00 01 02 03 04 05 06 07 08 09 10 11
EST 1hrly 19 20 21 22 23 00 01 02 03 04 05 06
crw consistency h h h h h h h h h h h M
heights consistency h h h h h h h h h h h M
bkw consistency h h h h h h h h h h h M
ekn consistency h h h h h h h h h h h M
pkb consistency h h h h h h h h h h h M
ckb consistency h h h h h h h h h h h M
After 00z Monday...
IFR in light rain and stratus at times Sunday night through