


Area Forecast Discussion
Issued by NWS Charleston, WV
Issued by NWS Charleston, WV
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124 FXUS61 KRLX 151727 AFDRLX AREA FORECAST DISCUSSION National Weather Service Charleston WV 127 PM EDT Tue Jul 15 2025 .SYNOPSIS... A tropically influenced airmass remains over the region with periodic low amplitude frontal systems passing through. Locally heavy showers and storms each afternoon are possible. && .NEAR TERM /THROUGH WEDNESDAY/... As of 125 PM Tuesday... Key Messages: * Tropically influenced airmass remains anchored across the region through the bulk of the forecast * Locally heavy, diurnally enhanced rainfall - water issues may accumulate over the next week * Wet microbursts may produce locally damaging wind gusts, but widespread severe weather is not expected in the next 7 days A mid-level ridge anchored over the southeast and nearly stationary boundary draped west to east across the forecast area are the dominant synoptic features affecting the region through the near term period. South of the front, precipitable water values are around the 75th+ percentile for this time of the year today, increasing to 90th+ percentile for Wednesday. Although mid-level lapse rates remain rather paltry (~5.5C/km) typical of a tropically influenced airmass, ample low level moisture and surface heating should yield 1000-2000J/kg MLCAPE by peak heating this afternoon. With deep-layer shear forecast to remain weak, the convective mode will strongly favor pulse-type cells and loosely organized multicell clusters. The probability of thunder in any 1-hour period peaks between 20Z and 00Z at around 30-40% for many locations in and near the higher terrain. Given the degree of instability and moisture, any storm will be capable of producing torrential rainfall with a few instances of gusty winds associated with wet microbursts. Convection will wane tonight with the loss of solar heating. However, lingering outflow boundaries from any afternoon activity could serve as a focus for isolated showers or a storm overnight, a low-probability scenario reflected in the NBM`s overnight PoPs of 10- 20%. For Wednesday, will see similar convective coverage (isolated to scattered) early afternoon into mid-afternoon, with an approaching mid-level wave from the west providing forcing for ascent for more substantial coverage heading into the late afternoon and evening hours. Models to depict a belt of stronger H500 flow associated with this feature across the Middle Ohio Valley yielding an uptick in deep layer shear to 35-40KTs. This should yield at least some potential for rotating storms in this area through the late afternoon and early evening. The primary threat with this activity would damaging wind gusts and locally very heavy rainfall, although the progressive nature of the storms should help to limit dwell time over any given location. While low level veering of the wind profile will be fairly limited, given the propensity for rotating storm and fairly low LCL values couldn`t rule out some sort of mesoscale oddity yielding a quick spin-up, but the probability is very low. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY/... As of 125 PM Tuesday... Not much change in the pattern is expected in the extended forecast with upper level ridging remaining over the southeast with high zonal flow across the north featuring periodic weak frontal boundaries that approach and stall over the region. This will maintain a tropically influenced airmass with relatively weak flow through the period. Central guidance continues to overdo afternoon mixed dew points with values in the upper 70s, reality will be closer to the lower 70s. This should keep heat indices below advisory criteria with highs in the low 90s. The main concern will continue to be locally heavy rain and with such a long period of diurnal enhanced locally heavy rain, we will continue to accumulate areas of overly moist soils more prone to flooding with additional heavy rainfall. Depending on antecedent conditions, may eventually need a flash flood watch for some areas. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... As of 125 PM Tuesday... As mentioned in the short term discussion, largely more of the same is expected heading into the weekend and into early next week with low amplitude frontal boundaries interacting with a tropically influenced air mass. Models are in fairly good agreement even through the end of the forecast with the subtropical ridge not expected to go anywhere in the foreseeable future. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... As of 125 PM Tuesday... A diurnal cumulus field will grow increasingly agitate through the afternoon with isolated thunderstorms possible across the lowlands. Should see better convective coverage closer to the mountains, but confidence is only high enough at EKN to include a TEMPO for TSRA at this time. For the remaining terminals, VCTS. Cloud cover overnight may impede dense fog formation, but any gaps in the clouds would allow for at least patchy fog development. Any fog that does develop dissipates through 13-14Z. Winds remain light and variable, except gusty and erratic near any thunderstorms. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 18Z WEDNESDAY... FORECAST CONFIDENCE: Medium. ALTERNATE SCENARIOS: Convective coverage this afternoon could affect more terminals than advertised. Fog tonight could be more dense or widespread than advertised. 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 16 17 18 19 20 21 22 23 00 01 02 03 EDT 1HRLY 12 13 14 15 16 17 18 19 20 21 22 23 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 M H H H H EKN CONSISTENCY H H H H H H H H H H H H PKB CONSISTENCY H H M 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 WEDNESDAY... Brief periods of IFR conditions possible under showers and thunderstorms, mainly during the afternoon and evening hours through the week. IFR or worse fog is also possible overnight, especially where any heavy rain falls during the day. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...None. OH...None. KY...None. VA...None. && $$ SYNOPSIS...JP NEAR TERM...JP SHORT TERM...JP LONG TERM...JP AVIATION...JP