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000 
FXUS61 KRLX 151122
AFDRLX

AREA FORECAST DISCUSSION
National Weather Service Charleston WV
622 AM EST Sun Dec 15 2019

.SYNOPSIS...
Mountain snow continuing through early Sunday. Another system 
approaches tonight into Monday with a wintry mix transitioning
to a heavy rain and flooding threat.

&&

.NEAR TERM /THROUGH TONIGHT/...
As of 335 AM Sunday...

Active weather continues in the near term period. Any lingering 
precipitation across the higher terrain will gradually taper off 
later this morning or early afternoon, as flow backs and becomes 
less favorable. Brief break in the precipitation in store for much 
of the day then, but by this evening, precipitation will increase in 
coverage again, as a low pressure system develops and approaches the 
area from the southwest. Strengthening llj across Ohio Valley area 
will aid in moisture transport and lift across the area overnight. 
Precipitation across much of the northern half of the CWA should 
generally start out as snow, but transition to a period of freezing 
rain and sleet as the morning progresses, as warmer air aloft takes 
hold, before transitioning to all rain by mid to late morning. 
Overall, accumulations will be light, and technically below advisory 
criteria for many zones, but with potential impacts due to the 
wintry mix, have elected to issue a winter weather advisory for late 
tonight through at least Monday morning across aforementioned
areas.

&&

.SHORT TERM /MONDAY THROUGH TUESDAY NIGHT/...
As of 351 AM Sunday...

     THREAT FOR FLOODING MONDAY AND MONDAY NIGHT IS INCREASING...

Aforementioned wintry mess will be ongoing Monday morning across
the far northern CWA. As the low level thermal profile warms,
all precip across our northern areas **should** change over to
all rain by roughly mid/late morning. However, some guidance
suites have been trying to trend a bit more southward with the 
overall storm system. If this southward trend continues, then a
wintry mix (especially sleet) could prevail longer across the 
current Winter Weather Advisory area. For areas farther south, 
a cold rain is expected Monday morning as H85 temps warm to 
around 8C, resulting in massive melting of any wintry precip 
before it reaches the ground.

After surface temps warm enough to minimalize any wintry precip,
attention then turns to the potential for flooding. Periods of
rain, heavy at times, are likely to occur Monday into Monday
evening. The placement of the heaviest rainfall will greatly
depend on how far north/south the warm/quasi-stationary front
moves during the day. As of this morning, the heaviest rainfall
is expected to occur across SE OH, far NE KY, and the northern
and western halves of WV. These areas are expected to receive
one to three inches of rainfall, which will likely lead to some
high water impacts at times. The threat for heavier rainfall 
should gradually diminish Monday night as the parent sfc low 
moves across, and then away from, our area. Cold air advection 
will then develop on Tuesday with temps likely falling some 
throughout the day. Precip will end Tuesday from west to east, 
with a brief period of snow possible on the tail end of the 
precip (although accumulations are currently expected to be 
rather minimal). Much colder conditions are then expected 
Tuesday night as surface high pressure builds into the area.

&&

.LONG TERM /WEDNESDAY THROUGH SATURDAY/...
As of 415 AM Sunday...

Quiet end to the work week expected as high pressure moves eastward 
across the area. Wednesday's temperatures are projected to be chilly 
with highs in the 30s (20s for the mountains) and lows in the teens 
and 20s; however, temperatures in the following days should warm as 
we approach the end of the week. Although clouds will clear during 
the day Wednesday, they are expected to build in once more Thursday 
night and remain through the end of the long term period as low 
pressure begins to move in from the west.

&&

.AVIATION /11Z SUNDAY THROUGH THURSDAY/...
As of 615 AM Sunday...

Light rain and snow showers will continue across the mountains
through 15Z, with brief restrictions. Otherwise, widespread 
MVFR affecting all TAF sites, through at least 18Z-22Z when 
gradual improvement to VFR is expected. Gusty westerly winds 
will continue to develop across the area and linger through 
16-19Z, with gusts in the teens to 20 kts.  

Another system, with the possibility of a wintry mix in spots, 
will return to the area by 00Z Monday, with widespread MVFR and
local IFR developing again, particularly after 06Z. Southern 
WV, NE KY, and southwest VA will see mainly rain with this 
system, while parts of southeast Ohio and northern WV will see a
wintry mix of snow, sleet, and freezing rain generally after 
01Z, with a gradual transition to rain towards the end of the 
TAF period. 

FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
     
FORECAST CONFIDENCE: Medium.

ALTERNATE SCENARIOS: Timing of improvements this afternoon may 
vary. Timing of precipitation and associated restrictions
tonight may vary from forecast. 

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 12/15/19
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  H    H    H    H    H    H    H    H    H    H    H    H
HTS CONSISTENCY  H    H    H    H    H    H    M    H    H    H    H    H
BKW CONSISTENCY  M    H    L    M    H    M    H    H    H    M    H    H
EKN CONSISTENCY  H    H    H    L    M    M    M    H    H    H    H    H
PKB CONSISTENCY  H    H    H    H    M    H    H    H    H    H    M    H
CKB CONSISTENCY  M    H    M    H    H    H    H    H    H    H    H    M

AFTER 12Z MONDAY...
IFR possible in rain Monday and Monday night, and in rain and 
snow showers on Tuesday and Tuesday night. 

&&

.RLX WATCHES/WARNINGS/ADVISORIES...
WV...Winter Weather Advisory from 7 PM this evening to 10 AM EST 
     Monday for WVZ009>011-017>020-028>032-039-040-521>526.
OH...Winter Weather Advisory from 7 PM this evening to 10 AM EST 
     Monday for OHZ066-067-075-076-083>085.
KY...None.
VA...None.

&&

$$

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