Area Forecast Discussion
Issued by NWS Charleston, WV-- Remove Highlighting --
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FXUS61 KRLX 230837
Area Forecast Discussion
National Weather Service Charleston WV
337 AM EST Mon Jan 23 2017
Stacked surface/upper low passes to the east today and tonight.
Progressively colder mid and late week with passage of a cold
.NEAR TERM /THROUGH TONIGHT/...
As of 235 AM Monday...
No major changes to the evolution and track of the stacked upper
level and surface low, but challenges remain with the QPF. The
RAP and especially the HRRR are still on the aggressive side,
giving more than an inch and a half in places, but will keep it
on the lower end of the models with about an inch to an inch and
a quarter through today. Rain shadow in place west of the
mountains currently due to the easterly component to the low
level flow, but eventual saturation will occur.
As the lows pass to the east, low level flow will back to the
northwest, transitioning the event to more of a northwest flow
scenario complete with a low level thermal trough. Cold air
advection is not much of a driver here, but dynamic cooling from
the proximity of the upper low brings highest ridge temperatures
below freezing, and subject to a change over to snow later this
evening and tonight. Accumulations will be 1 to 3 inches, but
look like they will be primarily above 3500ft. Greenbrier and
Tygart River valleys will likely remain as rain, or a rain snow
Still no headlines for water issues, but isolated pockets of
minor problems may occur due to persistence of rain and multi
.SHORT TERM /TUESDAY THROUGH WEDNESDAY NIGHT/...
As of 300 AM Monday...
Tuesday will see the shower activity wind down fairly quickly
from west to east as the strong low pressure system moves away.
Dynamic cooling will also wane as the system moves away, so
that lingering high elevation snow showers in the northern
mountains will change to rain showers before ending. Little
additional snow accumulation expected there. High pressure will
return Tuesday night with dry weather and near seasonable low
temperatures. The pattern will change beginning Wednesday as
northwesterly flow aloft drives a cold front southeastward into
our area later Wednesday and Wednesday night. A good warmup
again into the 60s Wednesday ahead of this cold front. Scattered
rain showers will spread southeast across most of the area
Wednesday night behind the cold front, with rain showers
changing to snow showers in the northern mountains, but with
.LONG TERM /THURSDAY THROUGH SUNDAY/...
As of 305 AM Monday...
For this period, established northwest flow aloft will bring a
series of upper disturbances and cold fronts, with progressively
colder air invading the area. These will bring scattered
showers for the later half of the week and into the weekend, but
with no storm systems expected, precip amounts will generally
be on the light side. Temperatures will cool to at or slightly
below normal by Friday. The scattered low elevation rain
showers, and high elevation snow showers, on Thursday will
change to mostly all snow showers Thursday night and continue
into the weekend. In general, little snow accumulation is
expected in the low lands, while some snow accumulations in the
mountains are likely.
.AVIATION /08Z MONDAY THROUGH FRIDAY/...
As of 1220 AM Monday...
Overall, deteriorating aviation conditions expected through the
TAF period as a strong upper level and surface low brings
copious rain to the central Appalachians and middle Ohio Valley.
Wind flows in the lower levels will keep the ceilings from
lowering too quickly across the lowlands, but saturation of
these lower levels will eventually bring conditions down to low
end MVFR to IFR. However, increasing winds will keep them in
check at the same time. A lot of moving parts to this forecast,
so some lower confidence is involved here. EKN will also hold
off the IFR with downsloping easterly winds.
LAMP guidance is the most pessimistic with the forecast, but the
pattern/timing is good, so tempered this with a blend of the MET
and MAV for ceilings and visibilities.
Heavier rain may need IFR TEMPOs.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z TUESDAY...
FORECAST CONFIDENCE: Low to Medium
ALTERNATE SCENARIOS: Conditions could fluctuate continuously
with rain bands from system overnight and tomorrow. Timing of
MVFR/IFR onset may vary slightly.
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 MON 01/23/17
UTC 1HRLY 08 09 10 11 12 13 14 15 16 17 18 19
EST 1HRLY 03 04 05 06 07 08 09 10 11 12 13 14
CRW CONSISTENCY H M M H M L M L M L L L
HTS CONSISTENCY H H H H H H M M M L L L
BKW CONSISTENCY M M M L L M M M M L L L
EKN CONSISTENCY H L H M M L M H H L L L
PKB CONSISTENCY L L H M M M H M L L L L
CKB CONSISTENCY L L L M M M M M H L L L
AFTER 06Z TUESDAY...
No widespread IFR weather is expected.