Area Forecast Discussion
Issued by NWS Charleston, WV-- Remove Highlighting --
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FXUS61 KRLX 241118
Area Forecast Discussion
National Weather Service Charleston WV
618 AM EST Tue Jan 24 2017
Low level moisture slow to exit with weak high pressure moving
in. Progressively colder mid and late week with passage of a
cold front and lingering northwest flow.
.NEAR TERM /THROUGH TONIGHT/...
As of 605 AM Tuesday...
Made some adjustments to some higher POPs along the line of
convergence slowly pushing eastward this morning. Coverage of
showers is not great, but expect this to continue for the next 3
hours or so before exiting.
As of 210 AM Tuesday...
Upper level trough aloft will continue its exit, with ridging
taking over later tonight.
Low level moisture connection will gradually erode after 15Z
this morning while warm air advection off the surface also
eliminates the thermal trough over the northeast mountains. The
result in the sensible weather will be low level cloud cover
that will be stubborn to dissipate, ending snow in the highest
ridges of the northeast mountains, and ending drizzle later this
Warm sector will return to the area going into the middle of the
.SHORT TERM /WEDNESDAY THROUGH THURSDAY/...
As of 335 AM Tuesday...
A pattern change to colder and somewhat unsettled weather begins
this period. After a warm and breezy Wednesday with high
temperatures around 60 degrees, the first in a series of cold
fronts will move across the area Wednesday night. Models show a
wave of low pressure will ride up the front and bring rain
showers Wednesday night. The front exits by Thursday morning,
and as colder air rushes in, rain showers will first change to
snow showers in the higher elevations. Cold advection and
moisture in northwest flow Thursday will bring scattered
showers, with snow levels lowering during day. Look for highs
Thursday in the 30s with brisk northwest wind.
.LONG TERM /THURSDAY NIGHT THROUGH MONDAY/...
As of 345 AM Tuesday...
Theme of the long term is northwest flow, with reinforcing cold
fronts, driving on and off snow showers through the weekend.
Models showing several upper level disturbances to occasionally
enhance the snow shower activity, especially in the mountains
with upslope flow. Confidence in timing any individual
disturbance is fairly low at this point, so basically maintain a
chance of snow showers during this period. No big storms or
extreme cold is expected this period, but some snow
accumulations are likely, especially in the mountains. By
Monday, models indicate a strong clipper type system with a
modest warm up and more organized precipitation.
.AVIATION /12Z TUESDAY THROUGH SATURDAY/...
As of 1225 AM Tuesday...
IFR/MVFR ceilings will be slow to improve with low level
moisture camped out over the area, and reluctant to exit. Still
getting patchy shower activity across the lowlands which will
continue for another 3 hours or so, and mountain precipitation
as well which contains light wet snow at times. Some IFR may
remain in place until the 16-18Z time frame this afternoon.
Guidance numbers are very aggressive on the restriction side,
but this is not unusual given the atmospheric set up and low
level moisture combined with northwest flow.
VFR eventually comes into play on the back end of the forecast.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z WEDNESDAY...
FORECAST CONFIDENCE: Medium.
ALTERNATE SCENARIOS: Ceilings may bounce on either side of the
1kft threshold for a few hours this morning.
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 TUE 01/24/17
UTC 1HRLY 10 11 12 13 14 15 16 17 18 19 20 21
EST 1HRLY 05 06 07 08 09 10 11 12 13 14 15 16
CRW CONSISTENCY M M M M M H M M M M L L
HTS CONSISTENCY H H H H M M M M M M L M
BKW CONSISTENCY H H H H H M M H H H M M
EKN CONSISTENCY M M M M L L M M M M M M
PKB CONSISTENCY L L M H M M M M M M L L
CKB CONSISTENCY H L M M M L M M M M L L
AFTER 12Z WEDNESDAY...
Intermittent IFR possible in snow showers Thursday night and