Area Forecast Discussion
Issued by NWS Charleston, WV-- Remove Highlighting --
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FXUS61 KRLX 221756
Area Forecast Discussion
National Weather Service Charleston WV
1256 PM EST Sun Jan 22 2017
Unseasonably warm through early next week with numerous rain
showers, as an upper low rotates through the area. Progressively
colder mid and late week with passage of a cold front.
.NEAR TERM /THROUGH TONIGHT/...
As of 1010 AM Sunday...
Made some minor changes to PoP based on current Radar and Meso
Model trends. Started the onset a little earlier across SW
Virginia, but made a tighter gradient across the northern edge
of the precip with chance PoP coming into Charleston at around
17Z. Will continue to monitor precip trends and update as needed
through the day. Have decided to leave high temperatures as is
for now since WAA should occur through the day.
As of 6 AM Sunday...
No significant changes made.
As of 320 AM Sunday...
Our weather will be dominated by upper disturbances rotating
around an approaching upper low from the west. With a deep and
moist southerly flow prevailing, temperatures will continue to
be well above normal for this time of year. Models have one
weakening disturbance lifting northward through the area today,
with a weakening band of rain showers. QPF amounts will be light
and greatest over the south. A stronger disturbance lifts north
over the area tonight, but this disturbance will tend to wrap
westward around the main approaching upper low. There will
likely be a brief break in the rain between these two systems,
but have tended to broadly cover higher pops given timing
uncertainty. Models also show a relative dry slot working into
the area tonight, but uncertainty again supports a general
coverage and continuation of the rain showers overnight, with
perhaps a bit of a rain shadow just west of the mountains given
a low level southeasterly flow. Instability is such that while
there may be a rumble of thunder with the second disturbance
tonight, not enough confidence to insert thunder in forecast.
Greatest QPF this period looks to be along and west of the Ohio
River and northeast Kentucky, as the wraparound band of rain
trains somewhat. However, not yet seeing a headline for any
flood watch, but will continue to highlight possibility in the
hazardous weather outlook.
.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 215 AM Sunday...
Heaviest band of rain should be departing to the north entering
the start of the short term, with models suggesting a lull/dry
slot for a short period of time in its wake. If nothing else,
this would be a lesser coverage period of the rain, but will
still carry the higher POPs given the abundant moisture and
myriad of vort maxes rotating through the 500mb flow. As the
parent upper level low exits to the northeast, there will be a
transition to more of a modest northwest flow scenario with some
upslope type precipitation. Cold advection will be modest,
however, and the chances for snow will be limited to the
northeast mountains. While the forecast snow amounts have been
upped slightly, not anticipating any issues with mountain snow
.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 215 AM Sunday...
Despite the lack of significant cold air on this side of the
northern hemisphere, a building ridge aloft out west will result
in a broad scale trough regime to set up for our area, changing
the storm track to more clipper systems in the coming days with
quick upper trough reinforcements of lower 500mb heights. Trend
will be colder with northwest flow patterns in the low levels
after a brief warm up mid week, and have extended chances for
snow showers into the weekend.
.AVIATION /18Z SUNDAY THROUGH FRIDAY/...
-- Changed Discussion --As of 1250 PM Sunday...
A busy forecast period with strong closed low pushing south and
east of the region. There will be several rounds rain rotating
northwest across the area as the low passes. For the most of
this afternoon conditions should remain mostly VFR with the
exception of BKW where SE flow has kept the moisture trapped
against the mountains. First weak wave out ahead of the
approaching system is spreading light rain into Southern West
Virginia, but conditions should not dip below VFR with this
first round, with the exception at CRW where MVFR conditions
could briefly occur.
More widespread rain overspreads the area from south to north
tonight, with conditions lowering to MVFR and possibly IFR in
heavier rain showers. Winds will also pick up, but should not be
much of an impact other than in the mountains.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z MONDAY...
FORECAST CONFIDENCE: Low to Medium
ALTERNATE SCENARIOS: Timing and location of southeast upslope
clouds today and tonight could vary at BKW. Conditions could
fluctuate continuously with rain bands from system overnight and
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.
UTC 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05
EST 1HRLY 13 14 15 16 17 18 19 20 21 22 23 00
CRW CONSISTENCY H M M M M M M M M H H L
HTS CONSISTENCY H M M H M M M M M M M L
BKW CONSISTENCY L M H H H H H M M M H L
EKN CONSISTENCY H H L L M H H H H H H M
PKB CONSISTENCY H H H H H H H M H M M L
CKB CONSISTENCY H H H H H H H M H H H L
AFTER 18Z MONDAY...
IFR in rain and fog possible Monday.
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