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fxus61 krlx 151235 

Area forecast discussion
National Weather Service Charleston WV
735 am EST sun Dec 15 2019

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 730 am Sunday...

Added some isolated rain showers this morning, mainly east of I-77.
These are associated with the tail end of a moisture plume off
Lake Michigan and should dissipate through mid-morning with
additional moisture fetch turned off as steering flow turned
westerly overnight. Also tweaked hourly temps up a little,
mainly across our northern half based on current conditions.

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 County Warning Area 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


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 County Warning Area. 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 850 mb 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 southeast 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 /13z 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 Virginia 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 weather forecast office 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 12 13 14 15 16 17 18 19 20 21 22 23
EST 1hrly 07 08 09 10 11 12 13 14 15 16 17 18
crw consistency h h h h h h h h h h h h
heights consistency h h h h M h h h h h h h
bkw consistency l M h M h h h M h h h h
ekn consistency h l M M M h h h h h l h
pkb consistency h h M h h h h h M h h h
ckb consistency M h h h h h h h h M h h

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.
Ohio...Winter Weather Advisory from 7 PM this evening to 10 am EST
Monday for ohz066-067-075-076-083>085.



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