Area Forecast Discussion
Issued by NWS Charleston, WV-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KRLX 201914
Area Forecast Discussion
National Weather Service Charleston WV
214 PM EST Fri Jan 20 2017
Active weather continues later this weekend as strong closed
low passes just to the southwest. Brief high pressure builds in
behind it midweek before another colder system passes towards
the end of next week.
.NEAR TERM /THROUGH SATURDAY/...
-- Changed Discussion --As of 21 PM Friday...
Warm air has surged into the region behind a warm front that
passed earlier today. Temperatures have already reached the low
60s across the Southern half of the forecast area. Although it
remains mostly cloudy this afternoon, there are some breaks in
the clouds and areas that see any persistent sunshine could
climb into the upper 60s.
Forecast soundings indicate enough low level moisture lingers
tonight for mostly cloudy skies to persist. This will also keep
us quite mild overnight with lows generally in the low 50s to
upper 40s. With the saturated ground, it is possible that we see
some fog develop by early Saturday morning, but this will depend
on cloud cover.
Tomorrow will be another very warm January day as warm air
advection continues. Weak overrunning starts again in the afternoon.
Right now the current thinking is that precipitation will
likely hold off until after 00Z, but have added some slight
chance to low chance PoP across the Southern forecast area
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.SHORT TERM /SATURDAY NIGHT THROUGH SUNDAY NIGHT/...
As of 315 AM Friday...
5h ridge axis shifts east of the forecast area on Saturday with
slight drying trend to start the period. Then flow trajectories
shift more toward the southwest as another warm front surges
north with over running precipitation. Atmospheric dynamics
weak, and will carry general chance pops and lighter qpf amounts
into saturday night.
Longwave trough axis then starts a trend to shift eastward late in
the period, perpetuated by a decent piece of energy working along
the southern periphery across the Tennessee Valley. Models tend to
keep best dynamics and moisture across southern half of our forecast
area with sfc low passing across NC.
Temps will remain well above normal through the period, with all
precipitation falling as rain through Sunday night. There even be a
few lighting strokes Sunday afternoon.
.LONG TERM /MONDAY THROUGH FRIDAY/...
As of 315 AM Friday...
Surface low tracks across to our south and then rides northward up
the East Coast with Mid Atlantic region remaining in a warm airmass.
Late in the period we see further indication that a change in
the longwave pattern is afoot, with cooler airmass working its
way into the upper midwest. By Thursday, we should see
temperatures return to more seasonal values. Noted some
variation with model solutions regarding the extended period.
Thus, used a general model blend throughout the period with a
few minor tweaks to pop and temperature values.
.AVIATION /19Z FRIDAY THROUGH WEDNESDAY/...
As of 1250 PM Friday...
A warm front has pushed through the region. Behind the front
there is generally broken clouds as ceilings range from VFR to
MVFR. Ceilings should continue to increase through the afternoon
as we become firmly entrenched in the warm sector. Isolated
showers will be possibly this afternoon across Northeast West
Virginia, but for the most part we will continue to dry out.
Confidence in the forecast starts to drop later tonight. There
will remain breaks in the clouds and with low level moisture in
place there is a chance that we could see some fog develop. Some
sites could possibly drop to IFR conditions.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z SATURDAY...
FORECAST CONFIDENCE: Medium.
ALTERNATE SCENARIOS: With broken clouds ceilings will likely
drop to MVFR at times. Fog development tonight may be more
widespread than 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.
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 H H L H H H H H H H M
HTS CONSISTENCY H H H M L H H H M M M L
BKW CONSISTENCY M M H H H H H H H H H M
EKN CONSISTENCY H H H L H H H H H H H L
PKB CONSISTENCY M H L M L L L L L L M L
CKB CONSISTENCY H M H H H L H H H H M L
AFTER 18Z SATURDAY...
IFR will be possible again Sunday through Monday with another