Area Forecast Discussion
Issued by NWS Charleston, WV
Issued by NWS Charleston, WV
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648 FXUS61 KRLX 182331 AFDRLX Area Forecast Discussion National Weather Service Charleston WV 731 PM EDT Fri Sep 18 2026 .WHAT HAS CHANGED... 729 PM Update... ~00z aviation discussion forecast updated. 142 PM Update... Rain chances have trended a bit lower this afternoon, but are still intact for the southern half of the forecast area through this evening. The forecast for this weekend and beyond remains on track, with shower and storm chances returning late Saturday night onward. && .KEY MESSAGES... 1) Post-frontal showers and storms are forecast to develop this afternoon and evening, followed by valley fog tonight. 2) Drier weather is forecast during the day Saturday, with more shower and storm chances arriving late Saturday night and beyond. && .DISCUSSION... KEY MESSAGE 1... The convectively-reinforced cold front has since moved south of the CWA, with low-level stratus advecting over the region. GOES-East visible imagery has detected the typical waveform structure to the post-frontal stratus deck, which will act to perturb the overturned airmass enough such that elevated showers and perhaps a few storms may develop this afternoon given the presence of the now-depleted EML. Severe weather nor flash flooding are expected with afternoon convection, and updrafts may be too shallow to reach heights high enough to generate lightning. PoPs have been delineated along a line from HTS-CRW-CKB, with the best chances for afternoon showers and storms along and south-to-southeast of that line. The potential for showers and storms will wane quickly by sunset this evening as the boundary-layer decouples, with valley fog expected to develop late tonight into Saturday morning across most of the CWA. Visibilities less than one-quarter of a mile will occur across some locales, along with the cloud deck descending to 100-200 ft AGL, with light, northerly winds becoming calm and easterly overnight. KEY MESSAGE 2... Fog and low stratus will begin to lift by the mid-morning hours Saturday as boundary-layer mixing commences. Entrainment of drier air in the mid-levels will allow stronger insolation to occur, boosting highs into the middle-upper 80s across the lowlands while cooler in the mountains. Dry weather is expected during the day Saturday given the strong warm nose/subsidence near 800 mb, but as the subtropical ridge continues to retrograde westward into the southern Great Plains, it will begin to flatten owing to the ejection of a neutrally-tilted shortwave trough over the central Rocky Mountains. The resultant interaction of these synoptic-scale features will allow a PV anomaly to shear off of an intense shortwave trough digging into Ontario, resulting in a belt of moist, isentropic ascent to advect across the Rust Belt and towards the northwestern portions of the CWA late Saturday night. The arrival of the leading shortwave perturbation will spawn a surface low in the Great Lakes region, with the cold front that moved through today undergoing warm-frontogenesis and lifting northeastward across the CWA. The subtropical ridge will lose its influence over the region by the latter half of the weekend as the aforementioned shortwave trough over the central Rocky Mountains progresses into the OH River Valley while broadening in amplitude. The presence of the increasing cyclonic flow aloft, which is forecast to be accompanied by strong jetlets in the mid/upper-levels, will provide large-scale forcing for ascent and daily chances for heavy showers and storms next week. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... VFR has moved back into the forecast area as SH/TS taper off and CIGs lift and scatter. An ISO SH or TS may still be possible this evening at CRW, BKW, or HTS as a slow moving cold front crosses the area. Confidence is not high in direct impact to these sites due to such an ISO nature, so it has been left out of the TAFs. Cloud cover is expected to filter out through the evening and overnight, except at sites in the mountains where low stratus will be probable. River valleys and sites where cloud cover clears out, namely PKB, HTS, and CRW will most likely see dense valley fog develop around or shortly after ~06z. IFR or lower conditions are expected with any fog. Outside of any stubborn MVFR CIGs with low stratus, VFR will resume by ~13-14z. W to N winds will become light to calm tonight, especially in the valley locations. This trend will likely remain in place through tomorrow, though a bias towards light N to NE winds will be common across the mountains and locations farther north and west. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SUNDAY... FORECAST CONFIDENCE: HIGH ALTERNATE SCENARIOS: Impacts and extent of fog tonight into Saturday morning may vary from the 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 22 23 00 01 02 03 04 05 06 07 08 09 EDT 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05 CRW CONSISTENCY H H H H H H H M L L L L HTS CONSISTENCY H H H H H H H H M M L L BKW CONSISTENCY H H H H H H M L L L L L EKN CONSISTENCY M M M M H M H H M L L L PKB CONSISTENCY H H H H H H H H L L L L CKB CONSISTENCY H H H H H H H M L L L L AFTER 00Z SUNDAY... IFR conditions possible in dense fog Saturday and Saturday night, especially in the mountain valleys. Chances for showers and thunderstorms Saturday afternoon and evening, and then likely on Sunday. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...None. OH...None. KY...None. VA...None. && $$ DISCUSSION...Sincavage AVIATION...LTC