Area Forecast Discussion
Issued by NWS Charleston, WV-- Remove Highlighting --
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FXUS61 KRLX 191030
Area Forecast Discussion
National Weather Service Charleston WV
630 AM EDT FRI AUG 19 2016
Weak upper level disturbances cross Friday and Saturday, then a
cold front crosses Sunday morning. Cool canadian high pressure
then takes hold for the early and middle part of next week.
.NEAR TERM /THROUGH TONIGHT/...
As of 240 AM Friday...
No significant changes were necessary to the previous forecast.
Weak shortwaves progged to move through the region today...along
with diurnal heating...will help to trigger showers and
thunderstorms once again. Storms will contain heavy
downpours...and be slow to move...but not overly concerned with
water issues as should be not overly widespread in nature.
Appears best location for activity today will be across the coal
fields and southwest Virginia...with activity decreasing late this
Overnight...expecting patchy fog and stratus to once again
develop...along with temperatures continuing to remain in the
upper 60s to lower 70s most locations.
.SHORT TERM /SATURDAY THROUGH SUNDAY/...
As of 330 am Friday...
Finally we look to break the hot and humid pattern by the end of
the weekend. Models agree on a significant amplification of the
northern stream this weekend...which will drive a strong cold
front across the area Saturday night and Sunday. At this distant
time frame...there are some timing differences among the
models. Using a consensus...we prog the front across the western
portion of the area Saturday night and across the east Sunday
morning. Ahead of the front will be the anomalously high moisture
content with PW`s aoa 2 inches. The combination of dynamics...moisture
and instability will bring high pops ahead of the front. Most of
these will be Saturday night and Sunday...so that saturday looks
to be another very warm and humid day with temps reaching well
into the 80s...with most of any diurnally driven pops in the west.
A more organized band of showers and storms will be likely ahead
of and along the front...although we continue to be somewhat
cautious with mesoscale influences that can distort the synoptic
scale. Nevertheless...going with at least likely pops with the
front. Saturday night should still be warm and humid except in the
far west where the front will pass and allow drier and a bit
cooler air to move in.
Finally...for Sunday...we look for a good progression of the front...exiting
the mountians by early afternoon. Much drier air and somewhat
cooler air will then quickly overspread the are behind the
front...with most of the precip ending by later afternoon in the
.LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/...
As of 330 am Friday...
Basically continued the previous forecast...with a slight
quickening of the next front Thursday.
Dry and cooler air continues to move in behind the front as an
airmass with Canadian origins settles in over the Ohio Valley.
High confidence continues for a dry and more comfortable weather
pattern through Wednesday. As mentioned in previous
outlooks...seasonable early morning fog will likely develop in the
climatological favored locations underneath the ridge next week.
Our next chance for precipitation will likely wait until Thursday
as a front...indicated on both the ECMWF and GFS...approaches
from the west.
Slightly lowered morning lows from Monday through Wednesday given
downward trend on ECMWF and GFS ensemble guidance. No major
adjustments to daytime highs through the period.
.AVIATION /12Z FRIDAY THROUGH TUESDAY/...
-- Changed Discussion --As of 530 am Friday...
Widespread mvfr/ifr fog and stratus across the area this morning
will generally improve to VFR conditions after 14Z with light
surface winds. Convection will fire again...mainly after
18Z...with greatest coverage across southern West Virginia and
southwest Virginia...creating brief MVFR and IFR conditions. Much
of the convection will die down after 02Z. However...fog and
stratus are likely again tonight...creating widespread mvfr and
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z SATURDAY...
FORECAST CONFIDENCE: Low.
ALTERNATE SCENARIOS: Timing and density of fog or stratus 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.
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 M M H M L M M M H H H M
HTS CONSISTENCY L M L M M M M M H H H M
BKW CONSISTENCY L M L M H M H H H H H L
EKN CONSISTENCY M M L M M H H H H H H M
PKB CONSISTENCY L L M M H H H H H H H M
CKB CONSISTENCY L H H H L H H H H H H M
AFTER 12Z SATURDAY...
Brief IFR conditions in scattered showers and thunderstorms Saturday
and Sunday, and in fog and stratus most mornings.
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