Area Forecast Discussion
Issued by NWS Charleston, WV-- Remove Highlighting --
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FXUS61 KRLX 291041
Area Forecast Discussion
National Weather Service Charleston WV
641 AM EDT THU SEP 29 2016
A large upper level low will bring wet weather today through
Friday. It pulls away in time to bring dry weather for the
weekend. High pressure continues the dry weather early next week.
.NEAR TERM /THROUGH TONIGHT/...
As of 420 AM Thursday...
Unsettled and cool weather for the near term period...as surface
cold/occluded front pushes east through the region today...and as
upper low...which will slowly dig south into Kentucky today...and
associated vort maxes...help to trigger showers and
thunderstorms...particularly this afternoon. There is the
possibility that a few storms could be on the strong
side...particularly across the eastern 2/3 of the CWA. Any breaks
that are able to develop in the cloud cover today will help to
destabilize the environment...and this combined with strong
shear...could lead to organized/strong convection...with damaging
winds a primary threat. Small hail can also not be ruled completely
out...or the possibility of an isolated tornado. SPC has placed the
majority of the CWA in a marginal risk...with southern/eastern WV
zones in a 2 percent for tornadoes. Will highlight in the HWO. In
addition to the severe threat...there will be heavy downpours with
any storms...but with the overall dry conditions and storm
movement...not concerned about issuing any water headlines. Based on
water vapor imagery...and model consensus...heavier axis of
moisture/precip should stay just to the east of the CWA...where
stronger low level winds will aid in higher moisture transport off
.SHORT TERM /FRIDAY THROUGH SUNDAY NIGHT/...
As of 420 AM Thursday...
Large upper level low over the lower Ohio Valley at the start of
the period swirls about there into Friday night, before moving
northward through Indiana Saturday and Saturday night, ending up
somewhere over lower Michigan by Sunday morning.
Showers are most likely across northeast portions of the area
Friday, as a ripple moves up the east side of the upper level low,
roughly along the surface occlusion. A thunderstorm is also
possible in that area, especially right along the occlusion
itself, where a narrow axis of mainly elevated instability will
exist. The occlusion will have thinned out this axis compared with
Coverage of showers decreases in the aging occlusion Friday night
through Saturday, with much of the area getting into a widening
The upper level low drifts eastward through the eastern Great
Lakes Sunday and Sunday night, and the dry slot opens up as drier
air arrives from the west. Dense fog is likely Sunday and Monday
mornings on account of very light flow, and the wet weather today
into Friday night.
No major changes were needed to temperatures, which are close to
guidance blends by day and bias corrected guidance by night, and
not far from normal overall.
.LONG TERM /MONDAY THROUGH WEDNESDAY/...
As of 230 PM Wednesday...
The pesky upper low will be out of our hair Sunday. In its wake
the region will experience rising heights and warming conditions,
potentially to well above normal once again next week.
.AVIATION /12Z THURSDAY THROUGH MONDAY/...
-- Changed Discussion --As of 630 AM Thursday...
Upper level low will continue to rotate across the area during the
period...with areas of showers...and thunderstorms...particularly
after 16-18Z. Expect brief gusty winds...heavy downpours...and
MVFR/IFR conditions at times...particularly in vicinity of
showers/storms. Bulk of convection will die off after
00Z...however...showers with restrictions...and areas of MVFR/IFR
cigs and vsbys will continue to linger for the remainder of the
period. Isold LIFR possible in low cigs and fog after 06Z.
FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 12Z FRIDAY...
FORECAST CONFIDENCE: Medium.
ALTERNATE SCENARIOS: Coverage and timing of convection this
afternoon...and resultant MVFR/IFR restrictions may vary from
forecast. Isold LIFR in question tonight.
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 H H H M H M M M M H H H
HTS CONSISTENCY M M M M M M M M M M L H
BKW CONSISTENCY M L H L M M M M M M M M
EKN CONSISTENCY H M M L L L L L L L L L
PKB CONSISTENCY H H H H M M M M M M H M
CKB CONSISTENCY M M H H H H H H H H H H
AFTER 12Z FRIDAY...
Areas of ifr possible in showers and thunderstorms through
Saturday, and in dense fog Sunday and Monday mornings.
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