Area Forecast Discussion
Issued by NWS Charleston, WV-- Remove Highlighting --
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FXUS61 KRLX 242352
Area Forecast Discussion
National Weather Service Charleston WV
652 PM EST Fri Feb 24 2017
A strong cold front crosses pre- and post- dawn Saturday
morning, followed by cooler weather for the weekend. A couple
systems next week with precipitation chances.
.NEAR TERM /THROUGH SATURDAY/...
As of 645 PM Friday...
See latest PNS/RER for info today`s records, February all time
records, and all time record meteorological winter highs.
Forecast generally in good shape. I tweaked hourly pops using
latest HRRR as an aid. There is still a concern for locally
damaging wind gusts after midnight across southeast Ohio,
northeast Kentucky and western West Virginia. The mid level
capping currently in place will erode overnight with the
approach of the front. With steepening low level lapse rates
along with the low dewpoint spreads in place...concern exist for
a congealing QLCS bringing down strong downdrafts.
As of 315 PM Friday...
After a record breaking warm afternoon and a dry, mild evening,
a strong cold front still appears on track to bring a line of
showers and thunderstorms through the area just ahead of it
overnight into Saturday morning. The main convective threat is
wind damage as super cells that form upstream evolve into a fast
moving squall line, but the hail and even tornado threat could
not be entirely ruled out if the low level shear can give rise
to sufficient mesoscale organization.
Dry slot behind the cold front will bring a quick end to the
showers and thunderstorms from west to east on Saturday, but
wrap around precipitation will then spread into northern
portions of the area later Saturday afternoon. These rain
showers will start turning over to snow showers late, as much
colder air advects in.
Used a blend of primarily near term sources for hourly
temperatures in the warm air ahead of the front tonight, and in
the cold advection behind the front on Saturday. Lows tonight
will be close to or equal to highs Saturday.
.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY/...
As of 330 PM Friday...
Cold air advection on W/NW flow will bring the chance for
upslope snow showers across the mountains through early Sunday
morning. Moisture is limited so accumulations will be very light
with generally less than an inch. High pressure builds over the
area on Sunday and although we remain dry it will be cool
relatively speaking. High pressure should hold through most of
the day Monday, however a southern stream system will approach
Monday evening and showers enter SW West Virginia by 00Z
Tuesday out ahead of a warm front.
.LONG TERM /SUNDAY NIGHT THROUGH FRIDAY/...
As of 335 PM Friday...
Zonal flow aloft will make for a progressive and active
pattern next week. Our first system brings showers Monday night
into Tuesday. The next system will arrive mid week as low
pressure tracking across the Great Lakes drag a cold front
through the region. Behind this colder air arrives again on NW
flow and this will bring a chance for snow showers across the
mountains towards the end of the work week.
.AVIATION /00Z SATURDAY THROUGH WEDNESDAY/...
As of 645 PM Friday...
A strong cold front will impact the area overnight tonight into
early Saturday morning. A line of strong showers and
thunderstorms just ahead of the cold front is timed to reach HTS
near 08Z, PKB 09Z, CRW 10Z, CKB,EKN, and BKW around 11Z.
Inserted tempo groups for HTS/PKB where 9 hour policy allows for
IFR TSRA with wind gusts to 40 kts. I covered the remainder of
the sites with 1 to 2 hour prevailing conditions of IFR gusty
showers. Some of the winds may approach severe limits across
Conditions will improve to VFR across the lowlands Saturday, as
dry air and a rising frontal inversion increases mixing heights
to about 5-6 kft.
South to southwest surface flow will be gusty at times ahead of
the cold front, shifting to west and remaining gusty behind the
cold front early Saturday morning. Moderate south to southwest
flow aloft ahead of the cold front into tonight will become
moderate west behind the cold front on Saturday.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SUNDAY...
FORECAST CONFIDENCE: Medium to high.
ALTERNATE SCENARIOS: May need to add TSRA to prevailing for
remainder taf sites. Gusty winds will tend to vary, especially
with the convection and the passage of the cold front overnight
tonight into Saturday 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.
UTC 1HRLY 00 01 02 03 04 05 06 07 08 09 10 11
EST 1HRLY 19 20 21 22 23 00 01 02 03 04 05 06
CRW CONSISTENCY H H H H H H H H H H H L
HTS CONSISTENCY H H H H H H M M M M M L
BKW CONSISTENCY H H H H H H H H H H H L
EKN CONSISTENCY H H H H H H H H H H H L
PKB CONSISTENCY H H H H H H H H M H H M
CKB CONSISTENCY H H H H H H H H H H H M
AFTER 00Z SUNDAY...
No widespread IFR conditions are expected at this time.