.LONG TERM...(FRIDAY NIGHT THROUGH THURSDAY)...A SIGNIFICANT BOUT
OF SEVERE WEATHER WILL BE POSSIBLE ACROSS THE SOUTHERN APPALACHIAN
REGION SATURDAY AFTERNOON AND EVENING ALONG AND AHEAD OF A COLD
FRONT PROGGED TO DROP SOUTH FROM THE OHIO VALLEY. SATURDAY
MORNING...A BROAD AREA OF SHOWERS /SOME LOCALLY HEAVY/... WILL MOVE
NORTHEASTWARD THROUGH THE REGION ALONG/AHEAD OF A WARM FRONT. THIS
WARM FRONT WILL STALL OUT ACROSS SOUTHWEST VIRGINIA AND FAR
NORTHEAST TENNESSEE BY THE EARLY TO MID AFTERNOON. IN WAKE OF THE
WARM FRONT...PRECIPITATION WILL TAPER OFF /AND PERHAPS SOME PARTIAL
CLEARING WILL OCCUR/...AS WINDS VEER AND INCREASE FROM THE
SOUTHWEST. AS A RESULT...AN UNSTABLE ENVIRONMENT WILL DEVELOP
WITHIN THE WARM SECTOR WITH CAPE VALUES ARE PROGGED TO BE AS HIGH
AS 2000 TO 3000 J/KG BY 21Z. THIS...COMBINED WITH BULK SHEAR VALUES
AS HIGH 60-70KTS WILL RESULT IN VERY GOOD STORM ORGANIZATION WITH
STRONG/ROTATING UPDRAFTS LATER IN THE DAY.
THE MAIN QUESTION THEN BECOMES STORM MODE. CURRENTLY...MOST
SOLUTIONS ARE SHOWING AN MCS/DERECHO FEATURE DROPPING SOUTHEASTWARD
OUT OF KENTUCKY DURING THE LATE AFTERNOON AND EARLY EVENING. THIS
ENVIRONMENT WOULD CERTAINLY SUPPORT A LONG-LIVED CONVECTIVE DERECHO
EVENT...WITH DERECHO COMPOSITE VALUES BETWEEN 1 AND 4 OBSERVED ON
THE LATEST NAM/SHEF RUNS. WITHIN THIS LINE...THE POTENTIAL FOR
SUPERCELL STRUCTURES WILL EXIST AS WELL. SOME SOLUTIONS EVEN SHOW AN
INITIAL BAND OF DISCRETE CELLS AHEAD OF THE MAIN LINE DURING THE MID-
AFTERNOON. THE COMBINATION OF HIGH HELICITY VALUES... HIGH 0-1 KM
SHEAR...AND STP VALUES AS HIGH AS 3 TO 5 /SHOWN BY THE NAM/ WOULD
DEFINITELY SUPPORT SOME TORNADO THREAT /ESPECIALLY NEAR AREAS WHERE
A MORE BACKED SURFACE WIND PROFILE AND IN AREAS NEAR ANY LINGERING
RESIDUAL OUTFLOW BOUNDARIES FROM EARLIER CONVECTION/. OVERALL
THOUGH...THE MAIN THREATS WILL BE WIDESPREAD CONVECTIVE DAMAGING
WINDS IN EXCESS OF 60-70 MPH AND LARGE HAIL. PERSONS THAT HAVE ANY
OUTDOOR ACTIVITIES PLANNED SHOULD PARTICULARLY MONITOR THE LATEST
OF SEVERE WEATHER WILL BE POSSIBLE ACROSS THE SOUTHERN APPALACHIAN
REGION SATURDAY AFTERNOON AND EVENING ALONG AND AHEAD OF A COLD
FRONT PROGGED TO DROP SOUTH FROM THE OHIO VALLEY. SATURDAY
MORNING...A BROAD AREA OF SHOWERS /SOME LOCALLY HEAVY/... WILL MOVE
NORTHEASTWARD THROUGH THE REGION ALONG/AHEAD OF A WARM FRONT. THIS
WARM FRONT WILL STALL OUT ACROSS SOUTHWEST VIRGINIA AND FAR
NORTHEAST TENNESSEE BY THE EARLY TO MID AFTERNOON. IN WAKE OF THE
WARM FRONT...PRECIPITATION WILL TAPER OFF /AND PERHAPS SOME PARTIAL
CLEARING WILL OCCUR/...AS WINDS VEER AND INCREASE FROM THE
SOUTHWEST. AS A RESULT...AN UNSTABLE ENVIRONMENT WILL DEVELOP
WITHIN THE WARM SECTOR WITH CAPE VALUES ARE PROGGED TO BE AS HIGH
AS 2000 TO 3000 J/KG BY 21Z. THIS...COMBINED WITH BULK SHEAR VALUES
AS HIGH 60-70KTS WILL RESULT IN VERY GOOD STORM ORGANIZATION WITH
STRONG/ROTATING UPDRAFTS LATER IN THE DAY.
THE MAIN QUESTION THEN BECOMES STORM MODE. CURRENTLY...MOST
SOLUTIONS ARE SHOWING AN MCS/DERECHO FEATURE DROPPING SOUTHEASTWARD
OUT OF KENTUCKY DURING THE LATE AFTERNOON AND EARLY EVENING. THIS
ENVIRONMENT WOULD CERTAINLY SUPPORT A LONG-LIVED CONVECTIVE DERECHO
EVENT...WITH DERECHO COMPOSITE VALUES BETWEEN 1 AND 4 OBSERVED ON
THE LATEST NAM/SHEF RUNS. WITHIN THIS LINE...THE POTENTIAL FOR
SUPERCELL STRUCTURES WILL EXIST AS WELL. SOME SOLUTIONS EVEN SHOW AN
INITIAL BAND OF DISCRETE CELLS AHEAD OF THE MAIN LINE DURING THE MID-
AFTERNOON. THE COMBINATION OF HIGH HELICITY VALUES... HIGH 0-1 KM
SHEAR...AND STP VALUES AS HIGH AS 3 TO 5 /SHOWN BY THE NAM/ WOULD
DEFINITELY SUPPORT SOME TORNADO THREAT /ESPECIALLY NEAR AREAS WHERE
A MORE BACKED SURFACE WIND PROFILE AND IN AREAS NEAR ANY LINGERING
RESIDUAL OUTFLOW BOUNDARIES FROM EARLIER CONVECTION/. OVERALL
THOUGH...THE MAIN THREATS WILL BE WIDESPREAD CONVECTIVE DAMAGING
WINDS IN EXCESS OF 60-70 MPH AND LARGE HAIL. PERSONS THAT HAVE ANY
OUTDOOR ACTIVITIES PLANNED SHOULD PARTICULARLY MONITOR THE LATEST
