Area Forecast Discussion
Issued by NWS Charleston, WV
Issued by NWS Charleston, WV
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012 FXUS61 KRLX 071805 AFDRLX Area Forecast Discussion National Weather Service Charleston WV 205 PM EDT Mon Sep 7 2026 .WHAT HAS CHANGED... The forecast for this week remains on track, with little change necessitated with the afternoon package. A low risk for flash flooding remains intact area-wide Wednesday night into early Friday morning as a cold front moves across the region. 18Z aviation discussion updated. && .KEY MESSAGES... 1) Dry and warm weather remains forecast into Wednesday afternoon, with some valley fog each morning through Wednesday. 2) Heavy showers and thunderstorms are forecast to arrive Wednesday night into early Friday morning, with localized flash flooding possible. && .DISCUSSION... KEY MESSAGE 1... In the mid/upper-levels, an Omega Block exists across the U.S., with the CWA beneath the inflection point of the easternmost closed low over the Canadian Maritimes and the subtropical ridge centered in the central Great Plains. Large-scale subsidence will persist across the region through Wednesday, with the mid-level warm nose becoming even more-pronounced Tuesday as the center of the subtropical ridge sloshes eastward following the collapse of the Omega Block. High temperatures for this afternoon will remain slightly above normal, with highs breaching 90 degrees for some locales across the lowlands Tuesday and Wednesday afternoon. The CWA will remain bereft of PoPs otherwise through Wednesday afternoon, with some bouts of valley fog during the predawn hours Tuesday and Wednesday amidst light winds. KEY MESSAGE 2... Active weather continues to be forecast late Wednesday night into Friday morning as a cold front approaches the region. The collapse of the Omega Block will have been induced by the westernmost shortwave trough currently digging into the Glacier Country, with said feature ejecting eastward and over the Great Lakes region by Thursday while remaining fairly progressive. Global NWP guidance has been in agreement with the base of the trough remaining north of the CWA, thereby placing the CWA beneath the right-entrance region to the intensifying, positively-tilted jetlets aloft. The advection of a tall, skinny EML will be driven by modest geopotential height falls, although CAPE values are forecast to be <1,500 J/kg amidst substantial cloud debris, which would limit the degree of diabatic heating. Orthogonally-oriented shear vectors throughout the cloud- bearing layer relative to the Appalachian Mountains will enhance the potential for upslope showers and thunderstorms Thursday, with PWATs climbing between 2-3 standard deviations above the climatological mean. However, the deep- and cloud-layer shear vectors will also become aligned with the cold front as it attains a southerly component to its movement by Thursday afternoon, thereby posing a risk for training storms within the favorable upslope flow regime. Localized flash flooding will be possible across portions of the CWA Thursday, especially with any portions of the linear convection that can become organized. Water-loaded cores may pose a risk for locally strong wind gusts, but the severe weather risk is low Thursday. PoPs will gradually wane from northwest-to-southeast late Thursday night into early Friday morning as the cold front sags southward and its axis of dilatation becomes increasingly divergent in the wake of the ejecting shortwave trough. That is, the passage of this cold front will do little to scour out the subtropical moisture that will have been intact days prior. The cold front is forecast to stall south of the CWA this weekend while continuing to decay, with off-and-on PoPs lasting throughout the upcoming weekend as a series of smaller-scale perturbations eject over the warm, and somewhat recycled, moist airmass as a weak surface high settles into the region. Muggy and warm conditions are also forecast to continue into next weekend. && .AVIATION /18Z MONDAY THROUGH SATURDAY/... VFR will prevail for the rest of the afternoon at all terminals, with the exception of KBKW, where MVFR stratocu will continue through the late afternoon hours before breaking up. Easterly winds will remain breezy at KBKW, with calm-to-light winds for all other terminals this afternoon. Valley fog will return tonight, with VSBY reductions ranging from MVFR-IFR, with LIFR/BLO MINS possible at KEKN prior to sunrise. A belt of southerly winds within the lowest few kft AGL as high pressure moves to the east of WV should prevent greater coverage of fog and/or low stratus from coming to fruition during the predawn hours Tuesday. Rapid improvements to VFR will arrive after sunrise Tuesday at all terminals. FORECAST CONFIDENCE: High through this evening, then low-medium for fog tonight. ALTERNATE SCENARIOS: The coverage and extent of fog for tonight may vary from the current 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 EDT 1HRLY 14 15 16 17 18 19 20 21 22 23 00 01 CRW CONSISTENCY H H H H H H H H H H H H HTS CONSISTENCY H H H 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 H H H H H H H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 18Z TUESDAY... IFR or lower conditions will be possible with valley fog Wednesday morning. Reductions to CIGs/VSBYs will accompany -SHRA/-TSRA late Wednesday night into early Friday morning. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...None. OH...None. KY...None. VA...None. && $$ DISCUSSION...Sincavage AVIATION...Sincavage