Severe Thunderstorm Warning 45, NWS Charleston, SC

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE CHARLESTON SC
225 PM EDT SAT JUL 6 2002

WATER VAPOR LOOP SHOWS LARGE UPPER RIDGE SPINNING OVER THE MID MS
VALLEY.  A WEAK S/W TROF WHICH TRIGGERED LAST NIGHTS MCS OFF THE
COAST IS EXITING TO THE SOUTHWEST...WHILE ANOTHER S/W TROF IS
APPROACHING FROM THE NORTH.  LATEST RUC AND VAPOR LOOP SHOWS THIS
WAVE CURRENTLY MOVING THROUGH NC AND THE VIRGINIAS.  SFC OBS SHOW A
WEAK COOL FRONT/BOUNDARY LYING ACROSS CENTRAL NC WHERE DEWPOINTS ARE
IN THE LOWER TO MIDDLE 60S JUST NORTH OF THE BOUNDARY.  AS THE S/W
TROF PUSHES SOUTH...IT WILL ALLOW THIS BOUNDARY TO SLIP
SOUTH...PROVIDING A FOCUS FOR SH/TS DEVELOPMENT THIS AFTERNOON AND
EVENING.  SPC CONTINUES TO HAVE THE AREA UNDER A SLIGHT RISK OF SVR THIS
AFTERNOON AND EVENING.  WILL CARRY CHANCE POPS THROUGH TONIGHT AS
CONVECTION AND THE FRONT APPROACH THE AREA.  AVN AND ETA MODELS BOTH
BRING A LARGE POCKET OF NVA ACROSS THE AREA SUN AFT AND INTO MON.
AVN STILL WANTS TO HANG ONTO PRECIP ALL DAY SUN...WHILE ETA ENDS THE
RAIN BY MORNING.  WILL LEAN TOWARD THE ETA.  SLIGHTLY COOLER TEMPS
WILL PREVAIL ON SUN

EXTENDED...UPPER RIDGE DOMINATES THE CENTRAL AND WESTERN PART OF THE
U.S. EARLY NEXT WEEK.  A STRONG UPPER LOW OVER THE NORTHEAST WILL
PULL OUT INTO THE NORTHERN ATLANTIC ON MONDAY...HELPING THE RIDGE
NOSE BACK INTO THE CAROLINAS.  BY TUE...UPPER RIDGE RETROGRADES BACK
WEST AND STRENGTHENS...ALLOWING A S/W TROF TO DIG ON THE EAST SIDE
OF THE RIDGE THROUGH THE MID MS VALLEY.  THE TROF IS OVER THE TN
VALLEY BY THU...BUT STRONG UPPER RIDGE OVER THE WEST AND THE
ATLANTIC WILL KEEP THE TROF NEARLY STATIONARY JUST TO OUR WEST.
LATEST AVN ALSO SHOWS A WEAK COOL FRONT STALLED OVER NORTHERN
SECTIONS OF SC.  FOR THIS REASON WILL GO WITH CHANCE POPS ON THU.  A
STRONGER WAVE WILL DIG DOWN ACROSS THE OHIO VALLEY BY LATE IN THE
WEEK.  WILL KEEP CHC POPS THROUGH SAT DUE TO THE UNCERTAINTY OF ITS
TRACK.

MARINE...NO MAJOR CONCERNS THROUGH THE SHORT TERM. WEAK FRONT WILL
MOVE S INTO THE WATERS LATE TONIGHT AND GRADUALLY WASHES OUT
SOMEWHERE ACROSS THE SC WATERS RESULTING IN A GENERAL E/SE FLOW TO
THROUGH THE PERIOD. MAY SEE WINDS BRIEFLY TURN MORE THE NE ACROSS
THE SOUTHERN WATERS LATE SUN AFTN INTO SUN NGT AS A WEAK INVERTED
MOVES INTO FL BUT ITS A TOUGH CALL ON WHETHER THE GRADIENT WILL BE
PINCHED ENOUGH TO KEEP THE NE FLOW IN PLACE. PLAN TO FORECAST E
WINDS FOR NOW BUT EITHER WAY WINDS AND SEAS SHOULD REMAIN FAIRLY
INSIGNIFICANT. ATTN SHIFTS TO MID WEEK AS ANOTHER CDFNT APPROACHES
BUT HAVE PLENTY OF TIME TO WATCH HOW THINGS EVOLVE SO WL KEEP A
CONSERVATIVE FCST.

CHS   72  87  71  89 /  40  20  00  00
SAV   73  87  71  88 /  40  20  00  00
CHL   75  84  73  85 /  40  20  00  00
NBC   75  87  72  87 /  40  20  00  00
RBW   71  88  70  89 /  40  20  00  00

.CHS...
GA...NONE.
SC...NONE.

PY/ST

GAZ087-088-099>101-114>119-137>141-SCZ040-042>045-047>050-062200-

SEVERE WEATHER OUTLOOK
NATIONAL WEATHER SERVICE CHARLESTON SC
1135 AM EDT SAT JUL 6 2002

...A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER SOUTHERN SOUTH
   CAROLINA AND SOUTHEAST GEORGIA THIS AFTERNOON AND EVENING...

A VERY MOIST AND UNSTABLE ATMOSPHERE WILL CONTINUE ACROSS SOUTH
COASTAL SOUTH CAROLINA AND SOUTHEAST GEORGIA THIS AFTERNOON. HIGH
TEMPERATURES ARE EXPECTED TO RISE INTO THE 90S ACROSS INLAND
SECTIONS THIS AFTERNOON. THE INTERACTION BETWEEN THIS
AIRMASS...DAYTIME HEATING...AND AN APPROACHING COOL FRONT WILL ALLOW
SCATTERED THUNDERSTORMS TO DEVELOP THIS AFTERNOON AND EVENING.

A FEW OF THESE STORMS MAY BECOME SEVERE...WITH DAMAGING WINDS AND
LARGE HAIL BEING THE MAIN THREATS.

STORM SPOTTERS AND EMERGENCY MANAGEMENT SHOULD CLOSELY MONITOR THE
WEATHER...AND BE PREPARED TO TAKE ACTION. STORM SPOTTER ACTIVATION
MAY BE NEEDED LATER THIS AFTERNOON.

STAY TUNED TO NOAA WEATHER RADIO...TV...OR YOUR LOCAL NEWS SOURCE FOR
THE LATEST WEATHER INFORMATION FROM THE NATIONAL WEATHER SERVICE.