Severe Thunderstorm Warning 60, NWS Columbia, SC

AREA FORECAST DISCUSSION...UPDATED
NATIONAL WEATHER SERVICE COLUMBIA SC
1205 PM EDT SUN MAY 7 2006

.SHORT TERM (REST OF TODAY)...
SURFACE WEDGE INCREASING OVER THE AREA THIS MORNING AND DURING THE
AFTERNOON. SPC JUST ISSUED WATCH BOX FOR MUCH OF SOUTHERN GEORGIA
BUT WEDGE SHOULD KEEP THUNDERSTORMS ELEVATED OVER THE CAE CWA.
TEMPERATURES HAVE COOLED OVER MORNING READINGS. CAE CURRENTLY 64
...AGS 66 AND OGB 71. CURRENT MESONET STATION PLOTS HAVE KERSHAW
DOWN TO 54 AND CHAPIN DOWN TO 58. SO WILL ISSUE UPDATED ZONE PACKAGE
WITH COOLER HIGH TEMPERATURES THIS AFTERNOON. LOWER 60S NORTH PORTION
...MID 60S CENTRAL AND UPPER 60S SOUTH PART. OTHERWISE...SURFACE
WINDS NORTHEAST 5-10 MPH.

&&

.PREVIOUS DISCUSSION...
(ISSUED 351 AM EDT SUN MAY 7 2006)

SHORT TERM (TODAY THROUGH TUESDAY)...
SATELLITE SHOWS LOTS OF CLOUDS ACROSS THE AREA THIS MORNING. 88D
SHOWS SOME LIGHT RAIN ACROSS THE UPSTATE/PIEDMONT...EVEN A RUMBLE
OR TWO OF THUNDER AS WELL. REGIONAL COMPOSITE SHOWS
ADDITIONAL...MORE WIDESPREAD RAINFALL MOVING E/NEWD TOWARDS THE
AREA FROM AL/GA. WV SHOWS S/W ENERGY SPINNING ACROSS MO/AR AND
MOVG EWD. SURFACE OBS SHOW RESIDUAL FRONTAL BOUNDARY STILL
LINGERING ACROSS THE CNTRL PORTION OF THE CWA THIS MORNING. COOLER
TDS IN THE UPR 40S/LOWER 50S ARND CLT/UZA WITH ARND 60/LWR 60S
FROM CAE SWD. BOTH NAM/GFS APPEAR TO BE A LITTLE TOO FAR
SOUTH...BUT FAIRLY CLOSE THROUGH THE DAY. NORTH OF THE BOUNDARY
HIGH PRESSURE EXTENDS NWD THROUGH THE MID ATLANTIC REGION. BOTH
NAM/GFS INDICATE WAVE TO DEVELOP ALONG THE BOUNDARY DURING THE DAY
AND MOVE OFF THE TONIGHT...WITH SOME DIFFERENCES IN STRENGTH AND
PLACEMENT BY MONDAY MORNING. BOTH NAM/GFS SHOW NICE ISENTROPIC
LIFT ACROSS THE AREA TODAY...ESPECIALLY THIS MORNING THROUGH
MIDDAY WITH DOWNGLIDE DEVELOPING OVERNIGHT. S/W EXPECTED TO MOVE
ACROSS THE AREA LATE TODAY INTO TONIGHT. SPC HAS THE EXTREME SE PTN
OF THE CWA OUTLOOKED FOR SLIGHT RISK THIS AFTERNOON. ALTHOUGH
MODELS INDICATE SOME SURFACE INSTABILITY DEVELOPING THROUGH THE
AFTERNOON...CLOUDS AND PCPN WILL LIKELY LIMIT CHANCES FOR SEVERE
STORMS. MODEL DIFFERENCES ON TUE SHOW NAM TO BE MORE MOIST AND
CLOSER WITH SURFACE LOW ALONG THE VA/NC COAST THAN GFS AS UPR
LEVEL SYSTEMS TRIES TO CUT OFF. LEFT SOME LIGHT POPS ON MONDAY DUE
TO MODEL UNCERTAINTY. ADDITIONAL MOISTURE BEGINS TO MOVE EWD BY
TUE. NAM MUCH FASTER WITH RETURN FLOW/ISENTROPIC LIFT LATE TUE.
GUIDANCE AND LOCAL EQUATIONS QUITE HIGH WITH POPS TODAY AND WILL
CONTINUE WITH CATEGORICAL POPS...BUT SHOW SOME SLIGHT DIFFERENCES
IN TEMPS THROUGH THE PERIOD AND WILL GO CLOSE TO CONSENSUS FOR
MOST OF FORECAST EXCEPT COOLER FOR TODAYS MAXES.

LONG TERM (TUESDAY NIGHT THROUGH SATURDAY)...
NEXT SYSTEM TO AFFECT THE AREA TUE NIGHT THROUGH POSSIBLY THU.
NAM/GFS SHOWING QUITE A FEW DIFFERENCES GOING INTO THE MIDDLE OF
NEXT WEEK. NAM CONTINUES WITH A FLATTER MID/UPPER LEVEL FLOW WITH
SEVERAL DISTURBANCES MOVING ACROSS THE AREA TUE/WED. THE GFS SHOWS
A MORE AMPLIFIED PATTERN WITH RIDING ACROSS THE AREA LATE
TUE/EARLY WED. WILL CONTINUE WITH CHANCE POPS TUE NIGHT THROUGH
FRI AND THE POSSIBILITY OF SOME DRIER AIR MOVING IN BY THE
WEEKEND. TEMPERATURES EXPECTED TO BE NEAR NORMAL THROUGH THE
PERIOD.

AVIATION...
ISENTROPIC LIFT WILL RESULT IN LOWERING CEILINGS AND VISIBILITIES
THIS MORNING. THE MAV MOS SUPPORTS MVFR OR IFR CONDITIONS DEVELOPING
TODAY. MIXING WILL PROBABLY HELP KEEP MAINLY MVFR CONDITIONS TODAY
BUT AREAS OF IFR SHOULD OCCUR IN HEAVIER RAIN. MAINLY IFR CONDITIONS
MAY DEVELOP TONIGHT BECAUSE OF CONTINUED HIGH LOW-LEVEL MOISTURE AND
DRYING ALOFT.

&&

.CAE WATCHES/WARNINGS/ADVISORIES...
SC...NONE.
GA...NONE.
&&

07

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE COLUMBIA SC
639 AM EDT SUN MAY 7 2006

GAZ040-063>065-077-SCZ015-016-018-020>022-025>031-035>038-041-081039-
AIKEN SC-BAMBERG SC-BARNWELL SC-BURKE GA-CALHOUN SC-CHESTERFIELD SC-
CLARENDON SC-COLUMBIA GA-EDGEFIELD SC-FAIRFIELD SC-KERSHAW SC-
LANCASTER SC-LEE SC-LEXINGTON SC-LINCOLN GA-MCCORMICK SC-MCDUFFIE GA-
NEWBERRY SC-ORANGEBURG SC-RICHLAND SC-RICHMOND GA-SALUDA SC-
SUMTER SC-
639 AM EDT SUN MAY 7 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR THE MIDLANDS OF SOUTH CAROLINA
AND THE CENTRAL SAVANNAH RIVER AREA OF GEORGIA.

.DAY ONE...TODAY AND TONIGHT
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY
NO HAZARDOUS WEATHER IS EXPECTED AT THIS TIME.

.SPOTTER INFORMATION STATEMENT...
SPOTTER ACTIVATION IS NOT ANTICIPATED.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE COLUMBIA SC
1241 PM EDT SUN MAY 7 2006

SCZ035>037-041-071745-

BAMBERG-BARNWELL-CALHOUN-ORANGEBURG-
1241 PM EDT SUN MAY 7 2006

...STRONG THUNDERSTORMS WILL IMPACT CALHOUN COUNTY...ORANGEBURG
COUNTY...BARNWELL COUNTY AND BAMBERG COUNTY THROUGH 145 PM EDT...

AT 1241 PM EDT NATIONAL WEATHER SERVICE DOPPLER RADAR INDICATED A
CLUSTER OF STRONG THUNDERSTORMS CENTERED ALONG A LINE EXTENDING FROM
11 MILES NORTHWEST OF ST. MATTHEWS TO 6 MILES SOUTHWEST OF
SNELLING...OR ALONG A LINE EXTENDING FROM 15 MILES SOUTHEAST OF CAYCE
TO 10 MILES SOUTHWEST OF BARNWELL...MOVING EAST AT 30 MPH. THIS
CLUSTER OF STRONG THUNDERSTORMS WILL AFFECT AREAS IN AND AROUND
SNELLING...NORWAY...NEESES...LIVINGSTON...BLACKVILLE...BARNWELL...
HILDA...KLINE...DENMARK AND ST. MATTHEWS THROUGH 145 PM EDT.

HAIL UP TO ONE HALF INCH IN DIAMETER...EXCESSIVE CLOUD-TO-GROUND
LIGHTNING AND GUSTY WINDS OF 35 TO 45 MPH CAN BE EXPECTED.

TTH