Area Forecast Discussion
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FXUS61 KRLX 110313
Area Forecast Discussion
National Weather Service Charleston WV
1013 PM EST Sat Dec 10 2016
A low pressure system crosses Sunday night and Monday. A cold
front crosses toward midweek bringing another arctic blast and
ushering in a more unsettled pattern through next weekend.
.NEAR TERM /THROUGH SUNDAY/...
As of 1010 PM Saturday..
Used the latest runs of the HRRR and RAP to give the POPs, QPF,
and snow grids some TLC along the far northern tier of the CWA
beginning tonight through 18Z Sunday. The changes do not amount to
all that much, and max out the totals to around 1.5 inches, but
for only a very small area up in far northern Perry County.
As of 200 PM Saturday...
Clouds will be increasing tonight as mid and high level moisture
advect into the area ahead of the next system. WAA will be
increasing over the upper Ohio Valley on low level SW flow. Some
good isentropic lift will develop as well, which will allow snow
to overspread portions of the upper Ohio Valley. It still appears
most of this will fall just north of the RLX CWA, perhaps clipping
Perry/Morgan over to Clarksburg/Elkins later tonight. The
consensus in the hi res models though keeps all of precip north
of the CWA with the GFS/ECMWF showing QPF over the aforementioned
areas. Given the amount of low level dry air in place...tend to
favor keeping the precip north of the area but will leave a tight
gradient of POPs across our northern fringe counties for some
wiggle room. The best chance for any accumulations would across
Perry/Morgan where a tenth or two is possible.
This all pushes north Sunday morning with mainly a dry forecast
for the daylight hours in broad SW flow aloft/SE flow at the
surface. Expect some sunshine in the afternoon across SW VA and a
good portion of WV. This along with downsloping should allow temps
to approach 50 in the typical banana belt areas along US 119/I 79
.SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/...
As of 250 PM Saturday...
The period starts with another front knocking on our doorstep.
Continuing WAA will push H85 temps to near +10C ahead of this
system, so predominantly a rain event for most areas. There will be
a small window for brief frozen precip in/near the mountains from
late Sunday evening into the pre-dawn hours Monday before too much
warm air moves in aloft. Forecast soundings show low level
thermal profiles favoring brief SN along the taller ridges with ZR
possible in mountain valleys. While a light glaze of ice is
possible, the changeover to rain should occur relatively quickly
Monday morning with all rain across the area before dawn.
Temperatures will remain cool but relatively mild compared to the
previous several days and rain should end west-to-east late
Monday into Tuesday with sfc high pressure building back in.
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 250 PM Saturday...
Confidence remains low concerning overall pattern evolution for the
long term. Regardless of spatial and temporal discontinuities in
model guidance, it does appear that another arctic airmass will
filter in by mid week. Multiple rounds of precipitation are also
possible through the period with any waves embedded in the larger
.AVIATION /03Z SUNDAY THROUGH THURSDAY/...
As of 630 PM Saturday...
For the area terminals, forecast is VFR ceilings and visibilities with
winds turning southerly less than 10kts.
Off the surface, low level flow to increase steadily through the
Warm front will develop north of the terminals with light snow
overspreading the region. Again, this will fall north of the PKB-
CKB-EKN line, and will end up in warm advection warm sector flow
through the period. Rain will move in from the west northwest
towards the end of the period, but will lie just beyond the
temporal scope of the TAFs.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z MONDAY...
FORECAST CONFIDENCE: Medium SE OH/N WV. High elsewhere.
ALTERNATE SCENARIOS: Light snow tonight may sneak into northern
TAF sites which would bring MVFR into play.
EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY
OF WFO 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 SUN 12/11/16
UTC 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14
EST 1HRLY 22 23 00 01 02 03 04 05 06 07 08 09
CRW CONSISTENCY H H H H H H H H H H H M
HTS 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 possible in rain developing Sunday night.