Area Forecast Discussion
Issued by NWS Charleston, WV-- Remove Highlighting --
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FXUS61 KRLX 201001
Area Forecast Discussion
National Weather Service Charleston WV
601 AM EDT WED JUL 20 2016
Drier/more stable air today. Upper level high pressure builds
over central U.S. with a warming trend through the end of the
week. Weak disturbances could drop southeast around ridge.
.NEAR TERM /THROUGH TONIGHT/...
6 AM update. No significant changes.
Previous discussion... High pressure will dominate today and
tonight. Although a summer sun will push temperatures to near 90
degrees this afternoon...much drier air that has worked into the
area with the high pressure will keep humidity levels down today.
So look for abundant sunshine today...after early morning river
valley fog due to favorable radiational cooling under the high
pressure. The drier air will allow for a large diurnal range in
temperature...with lows tonight dropping well down in the 60s and
allowing for some more early Thursday morning river valley fog.
.SHORT TERM /THURSDAY THROUGH SATURDAY/...
Upper ridge continues to strengthen and build eastward at the start
of the period...with an increase in heat and humidity as we progress
into the weekend. Dew points will gradually climb into the 70s by
Friday into the weekend...and this combined with temperatures in the
90s...will create heat indices over 100 across much of the lowlands
Friday into the weekend. Will continue to highlight this in the
HWO...as it is looking more and more likely heat advisories will be
Most of the period should remain relatively dry...however...there
exists the possibility of disturbances aloft moving southeast into
the region at times...triggering showers and thunderstorms...with
heavy downpours expected with any storms. Still a little too far out
to determine exact timing and path of any
disturbances...but...maintained a general chance to slight chance in
the forecast at times during the period
.LONG TERM /SATURDAY NIGHT THROUGH TUESDAY/...
The heat will continue thru much of the extended with this weekend
serving as the apex as the upper level ridge axis plagues the
central parts of the country...keeping the extreme heat at bay
thankfully. Still...highs in the low to mid 90s with dewpoints in
the lower 70s will create heat index values likely eclipsing the
100 degree mark Saturday and Sunday. Will keep the mention of
potential heat advisories in the current HWO. A caveat in
realizing such thresholds will depend on areal coverage of any
convection. A moisture axis from the upper level wave that comes
thru Friday night may linger on Saturday as the ridge axis makes
subtle changes. This may provide the lift for aftn convection once
any mid level cap is broken. We have included some chance pops in
for Saturday afternoon...centered over SE OH. Our far NE zones may
stay capped to keep the day dry. Another upper level wave will
help to flatten the ridge some on Sunday and especially early next
week with increased threat for shra/tsra.
.AVIATION /10Z WEDNESDAY THROUGH SUNDAY/...
12Z Wednesday thru 12Z Thursday...
High pressure will provide VFR mostly clear conditions through
the period...except for IFR/LIFR river valley fog til 13z this
morning mainly at CRW and EKN. For tonight expect less river
valley fog...but briefly IFR at EKN and CRW 08z-10Z Thursday
Near calm winds by night...and north to northwest wind 4 to 8 kts
CONFIDENCE AND ALTERNATE SCENARIOS...
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z THURSDAY...
FORECAST CONFIDENCE: High.
ALTERNATE SCENARIOS: None.
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 10 11 12 13 14 15 16 17 18 19 20 21
EDT 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17
CRW CONSISTENCY L L L H H H H H H H H H
HTS CONSISTENCY M L M H H H H H H H H H
BKW CONSISTENCY H H H H H H H H H H H H
EKN CONSISTENCY L L L H H H H H H H H H
PKB CONSISTENCY L L L H H H H H H H H H
CKB CONSISTENCY L L M H H H H H H H H H
AFTER 12Z THURSDAY...
No widespread IFR expected.