Area Forecast Discussion
Issued by NWS Charleston, WV

Current Version | Previous Version | Graphics & Text | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
268 FXUS61 KRLX 210555 AFDRLX Area Forecast Discussion National Weather Service Charleston WV 155 AM EDT Sun May 21 2017 .SYNOPSIS... A warm front will drift slowly to the north overnight. A cold front crosses from the west Sunday night. High pressure crosses Monday night, then low pressure and unsettled conditions for the remainder of the work week. && .NEAR TERM /THROUGH TODAY/... As of 1020 PM Saturday... With convection in eastern Kentucky, and a long duration of rounds of showers and thunderstorms starting early Sunday and going well into Sunday night, opted to not let flash flood watch expire, and continued through Sunday night. Later shifts can determine if the flood watch needs expanded, but the current watch largely covers the intersection of lowest flash flood guidance and highest forecast rainfall amounts. The eastern kentucky convection was the result of late day recovery for the second straight day, along with a theta-e axis along a warm front, and outflow boundaries. As of 840 PM Saturday... A rather active evening of convection roughly along a theta-e axis along a warm front over the area was winding down with loss of heating. After a brief lull overnight, bands of convection along outflow boundaries and, eventually a cold front, will arrive from the west. The initial line of convection upstream will also weaken with the loss of heating. This could stiff arm arrival on our western flank until 09Z or so, if it dissipated altogether, but have chance pops well east after 06Z. Even a late arrival could create an 18-hour window of rounds of showers and thunderstorms, until the cold front finally crosses early Monday morning. The flood watch will expire at 10 PM, but will have to watch the potential for excessive rainfall Sunday through Sunday night. As of 305 PM Saturday... Frontal boundary will lift northward this afternoon and evening. With a moist airmass in place with afternoon heating will fire convection just about anywhere over the area. With weak flow aloft these storms will be slow movers. Any one of these storms could product upwards of an inch or two. With the saturated ground across the Southern Coalfields, went ahead an issued FFA for that area. Cold front to our west will continue to move eastward overnight and should be on our doorstep by 12z Sunday. Increased pops as front approaches. Generally went with a blend of guid for temps through out. && .SHORT TERM /TONIGHT THROUGH TUESDAY/... As of 305 PM Saturday... Cold front pushes through Sunday night and exits early Monday morning. Pwats increase with limited sfc CAPE and deep layered shear. Therefore, expect an environment conducive to flash flooding and not severe for Sunday. WPC has most of WV under a Slight risk for excessive rainfall Sunday. A flash flood watch may be required. Behind the front, expect a period of cooler and drier air early Monday into Tuesday. && .LONG TERM /TUESDAY NIGHT THROUGH SATURDAY/... As of 305 PM Saturday... The chances for rain return by midweek with the next frontal system. Temperatures will return to a more seasonable level during this period. && .AVIATION /06Z SUNDAY THROUGH THURSDAY/... As of 155 AM Sunday... Convection is dying down across the Ohio Valley and most of the region should be dry the remainder of the night. HTS received over an inch of rain yesterday afternoon with thunderstorms and this added moisture will possibly help produce some fog and IFR conditions through daybreak there. There is some decent winds in the lower boundary layer which could cause enough turbulent mixing to hinder fog development. The other trouble spot through the morning hours will be BKW, where upsloping southeast flow is producing some low stratus over the mountains. They will likely remain on the verge of IFR ceilings and there is quite a bit of uncertainty on how low ceilings may fall through morning. A cold front is expected to bring a long window of widespread showers and thunderstorms today. Should see rain pushing into the far east of the Ohio River close to dawn and the unsettled conditions will last well into Sunday night. MVFR conditions will be common Sunday, with IFR possible in heavier rain and thunderstorms. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z MONDAY... FORECAST CONFIDENCE: Low to Medium ALTERNATE SCENARIOS: Development and placement of fog may vary through the early morning hours. Conditions will vary in showers and thunderstorms on Sunday. 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. DATE SUN 05/21/17 UTC 1HRLY 06 07 08 09 10 11 12 13 14 15 16 17 EDT 1HRLY 02 03 04 05 06 07 08 09 10 11 12 13 CRW CONSISTENCY H H H H H H H H H M M L HTS CONSISTENCY H H M L L H L L H M L L BKW CONSISTENCY M M M M L L M M M M M L EKN CONSISTENCY M M H H H H H H H H H M PKB CONSISTENCY H H H H H H H H M M M L CKB CONSISTENCY H H H H H H H H H H H M AFTER 06Z MONDAY... IFR possible in showers and thunderstorms Sunday night, fog and stratus late overnight Sunday night into Monday, and in fog overnight Monday night into Tuesday morning.. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...Flash Flood Watch through late tonight for WVZ005-013-024>026- 033-034-515-516. OH...None. KY...Flash Flood Watch through late tonight for KYZ105. VA...Flash Flood Watch through late tonight for VAZ003-004. && $$ SYNOPSIS...TRM NEAR TERM...JS/TRM SHORT TERM...JS/JW LONG TERM...JS/JW AVIATION...MPK is the U.S. government's official web portal to all federal, state and local government web resources and services.