Area Forecast Discussion
Issued by NWS Charleston, WV-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
FXUS61 KRLX 220957
Area Forecast Discussion
National Weather Service Charleston WV
545 AM EDT SUN MAY 22 2016
Mid and upper level low drops southeast and lingers in mid Atlantic
states into Monday night. High pressure over Ohio/Tennessee Valleys
Monday into Tuesday. Warmer for mid and late week.
.NEAR TERM /THROUGH TONIGHT/...
At the lovely hour of 07z...mid level circulation around kduj in Pa
with weak lobe of vorticity swinging through nrn Wv panhandle toward
the nrn Wv mtns. Clearing moved into the Oh Vly counties and should
reach Grundy Va shortly. A hour or two earlier on this graveyard
shift...thought predawn valley fog would form in southeast Ohio to
Hts vcnty...but my confidence is lowering at 07z.
Difficult to figure how much clearing occurs before the early May
sunrise in the I-79 corridor. In any case...the mixing today will
lift the clouds. We will have to look out the north window
today...then toward the northeast tonight...as the steering flow
veers from northwest early today...becoming northeast tonight. This
is in response to the mid level circulation dropping se into
northern Virginia by 00z Monday...then to the Nc/Va coast by 12z
With the drier air in the Oh River counties...only mentioned a 20/30
percent chance of a mid to late afternoon shower. Highest pops for
that time frame remain over our central Wv mountain counties back
west to around Sutton...Glenville...and West Union. Will continue
to mention a small chance of a thunderstorm in Wv.
Precipitable water around 0.75 inch...so thinking the showers will
not be as heavy as the local showers on Saturday afternoon and
evening. The wettest area the past 48 hours has been our central
mountains including the headwaters of the Elk...Gauley...West
Fork...Little Kanawha...Buckhannon...and Tygart Valley. Our 88d
storm total rain estimate was reset to zero around 0730z.
A waning chance of showers remain overnight across the mountain
.SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/...
The short term forecast sees the slow filling of the closed upper
low over the Carolina/mid Atlantic coastal area...and a slow drift
and continued weakening into the Maritimes of Canada by mid week.
This marks the beginning of high pressure gaining control of the CWA
and finally eliminating chances for showers and thunderstorms that
linger with the upper low to the east.
There will be a trend of heights increasing...as the surface high
begins its push off the east coast and takes its place as a Bermuda
High...with ridging over the Appalachians heading into the extended
forecast. Through mid week...this means a continued slow
warming...and largely dry weather until moisture and instability
increase into the end of the week.
Overall grid changes are modest. Bring the pops a bit further west
on Monday...and mostly cosmetic changes to the temperatures through
the short term.
.LONG TERM /THURSDAY THROUGH SATURDAY/...
The dry weather we get on Tuesday will be short-lived as upper
ridge breaks down and is replaced with zonal flow aloft. This
pattern is looking very summer-like as we end up on the edge of
the Bermuda High. Southwesterly flow will push warm and moist air
from the Gulf of Mexico into the region...and dew points may
approach 70F by the end of the work week. There will be a threat
for showers and thunderstorms each day from mid week to the
weekend in the moist airmass as we maximize daytime heating in the
.AVIATION /10Z SUNDAY THROUGH THURSDAY/...
-- Changed Discussion --Confidence rasied to medium for the 12z set of tafs. It was tough to
figure ceilings and fog for the 06z to 12z this morning. Despite
the clearer sky...the fog was very limited in forming across
southeast Ohio and along the Ohio River. Clearing line nr Pkb to
Crw around 10z.
Still widespread ifr ceilings over the mountain counties of WV
at 10z...but have ceilings lifting this morning.
A mid level circulation drops southeast out of Pennsylvania toward
northern Virginia after 21z today. In respond...shower coverage
should increase between 15z to 18z vcnty ckb to ekn...then reach
south toward the Crw to Bkw vcnty during the 19z to 00z period.
Drier dew points and mixing should lift ceilings today. So after
15z...have mostly 4 to 6 thsd ft bkn ceilings...except over
mountains with 2 to 3 thsd ft. An isolated thunderstorm may develop
over West Virginia after 18z thru 00z Monday.
Scattered showers linger ekn-bkw after 00z to 06z as flow veers more
toward the northeast. Ifr in ceilings may develop over the Wv
mountain counties again 06z to 12z Monday. Late night fog at
Charleston may be dependent on coverage of late day showers and
the lingering cloud cover overnight.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z MONDAY...
FORECAST CONFIDENCE: Medium.
ALTERNATE SCENARIOS: Fog more extensive than forecast for 06z to 12z
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 M H H H H H H H H H
HTS CONSISTENCY M M M H H H H H H H H H
BKW CONSISTENCY L L L M M M M H H H H H
EKN CONSISTENCY L L L L L L M M M M M M
PKB CONSISTENCY L M M H H H H H H H H H
CKB CONSISTENCY M M M M M M M H M M M M
AFTER 12Z MONDAY...
IFR in fog possible late Monday night into Tuesday morning.
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