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
-- Remove Highlighting --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KRLX 270948 AFDRLX Area Forecast Discussion National Weather Service Charleston WV 548 AM EDT Thu Apr 27 2017 .SYNOPSIS... A cold front crosses late today and this evening. Weak high crosses Friday morning. A front sags into the area and then retreats this weekend. A stronger cold front crosses Monday. && .NEAR TERM /THROUGH TONIGHT/... As of 545 AM Thursday... Showers and thunderstorms are likely today, as a cold front approaches from the west-southwest. The front was just east of the Mississippi River early this morning, with convection ahead of it along the nose of a jet max through the base of an upper level short wave trough, pushing into eastern Tennessee early this morning. The cold front is progged to move through late this afternoon and this evening, as the short wave trough lifts through the middle and upper portions of the Ohio Valley. Meanwhile, the jet max approaches, but remains mainly southwest of the area through tonight. All of this places the timing of the showers and thunderstorms moving west to east across the area squarely on today, with the forcing weakening late. CAPE is progged to reach 1500 J/kg ahead of the front. Deep layer shear is impressive, exceeding 80 kts in the 0-8km layer, but the effective inflow layer is limited by a relatively stable layer about h9-h9, thus limiting the effective bulk shear. Midday through mid afternoon across central and eastern portions of the forecast area appear to carry the best potential for strong wind gusts and small hail. Clearing takes place behind the cold front tonight, as high pressure builds in toward dawn. Fog is likely to form toward dawn as the boundary layer becomes calm, with low clouds possible in the mountains. Adjusted temperatures today to get highest values ahead of precipitation. Faster timing of the front, and associated precipitation result in slightly lower highs than previous forecast. Lows tonight are close to latest guidance as well as previous forecast. && .SHORT TERM /FRIDAY THROUGH SUNDAY/... As of 545 AM Thursday... High pressure Friday, with dry and warmer conditions, with warm frontal boundary lifting north across the region. The warm frontal boundary will linger across the Ohio Valley during the weekend, with periods of showers and thunderstorms, particularly across parts of southeast Ohio, with heavy downpours expected. In addition, some of the storms could be on the strong side late Friday night/early Saturday, with strong winds the primary threat, particularly across western zones. A slight risk is in place across parts of northeast KY, with a marginal risk across western 1/3 of CWA. Warm frontal boundary will continue to lift north over the weekend as upper trough across central U.S. continues to deepen. Showers and thunderstorms, along with increasing heat and humidity can be expected over the weekend as a result. && .LONG TERM /SUNDAY NIGHT THROUGH WEDNESDAY/... As of 545 AM Thursday... Cold frontal boundary associated with the system will push through the region Monday and Monday night, with additional rounds of showers and thunderstorms, some of which will be heavy at times. Still a bit too early to pinpoint/determine any severe threat. Behind the front, cooler and unsettled weather takes hold for Tuesday, followed by another system by mid week. && .AVIATION /09Z THURSDAY THROUGH MONDAY/... As of 215 AM Wednesday... MVFR fog may form in the Tygart Valley. Otherwise, a VFR overnight and early Thursday morning precedes a cold front approaching from the west. That cold front is likely to bring showers and thunderstorms from west to east across the area late Thursday morning through Thursday afternoon. So far have coded VCTS / CB at this distance, but any thunderstorm can bring IFR conditions. Strong wind gusts and hail are also possible. Clearing will take place behind the cold front tonight, although MVFR stratocu may linger in the mountains, and fog may start to form late. Light east to southeast surface flow overnight will become south to southwest around 10 kts Thursday, and then light west to southwest behind the cold front tonight. Moderate to strong south to southwest flow aloft overnight will gradually diminish to moderate south to southwest on Thursday, and then light to moderate southwest Thursday night. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 06Z FRIDAY... FORECAST CONFIDENCE: Medium to high. ALTERNATE SCENARIOS: Fog may or may not develop at EKN overnight. Timing and coverage of showers and storms, and associated MVFR or worse conditions, may vary on Thursday. Formation of MVFR stratocu behind the cold front Thursday night may vary. Fog may start to form by 06Z Friday. 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 THU 04/27/17 UTC 1HRLY 09 10 11 12 13 14 15 16 17 18 19 20 EDT 1HRLY 05 06 07 08 09 10 11 12 13 14 15 16 CRW CONSISTENCY H H H H H H H H H L H L HTS CONSISTENCY H H H H H H H H M L H M BKW CONSISTENCY H H H H H H H H H H H M EKN CONSISTENCY M M M M H H H H H H H M PKB CONSISTENCY H H H H H H H H H H M L CKB CONSISTENCY H H H H H H H H H H H L AFTER 06Z FRIDAY... IFR fog possible Friday morning. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...None. OH...None. KY...None. VA...None. && $$ SYNOPSIS...TRM/SL NEAR TERM...TRM SHORT TERM...SL LONG TERM...SL AVIATION...TRM is the U.S. government's official web portal to all federal, state and local government web resources and services.