Area Forecast Discussion
Issued by NWS Columbia, SC

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary On
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
000
FXUS62 KCAE 022146
AFDCAE

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
546 PM EDT TUE SEP 2 2014

.SYNOPSIS...
HIGH PRESSURE WILL EXTEND INTO THE FORECAST AREA FROM THE ATLANTIC
THROUGH THURSDAY. A PERSISTENT UPPER RIDGE WILL HELP MAINTAIN THE
HOT TEMPERATURES.

&&

.NEAR TERM /UNTIL 6 AM WEDNESDAY MORNING/...
SIGNIFICANT INSTABILITY COUPLED WITH SURFACE CONVERGENCE NEAR
SURFACE TROUGH...SEA BREEZE...AND OUTFLOW BOUNDARIES RESULTING IN
CONSIDERABLE THUNDERSTORM COVERAGE OVER THE FA CURRENTLY. UPPED
POPS IN THE NEAR TERM. DUE TO SIGNIFICANT INSTABILITY AND SOME DRY
AIR ALOFT...THERE WILL CONTINUE TO BE THE THREAT FOR SOME SEVERE
CELLS...ALONG WITH A LOCALIZED HEAVY RAIN AND FLOOD THREAT DUE TO
SLOW STORM MOTION. WILL EXPECT CONVECTION TO GRADUALLY DISSIPATE
THIS EVENING. RAIN COOLED AIR AND LIGHT WINDS LATE TONIGHT MAY
PROVIDE A THREAT OF PATCHY FOG...DEPENDING ON EXTENT OF ANY
LINGERING CLOUD COVER.

&&

.SHORT TERM /6 AM WEDNESDAY MORNING THROUGH WEDNESDAY NIGHT/...
THE SURFACE RIDGING EAST AND SOUTH OF THE FORECAST AREA WILL
CONTINUE TO DOMINATE. A WEAKENING FRONT APPROACHING FROM THE
NORTHWEST SHOULD STALL BEFORE REACHING THE AREA TO OUR NW ACROSS
THE MOUNTAINS. STRONG HEATING WITH DEEP MOISTURE PLUS SOME
CONVERGENCE ASSOCIATED WITH LEE-SIDE TROUGHING SHOULD HELP SUPPORT
THUNDERSTORMS. COVERAGE SHOULD BE LIMITED BECAUSE OF CONTINUED
UPPER-LEVEL RIDGING AND SLOW STORM MOVEMENT. THE GUIDANCE
CONSENSUS SUPPORTS POPS AROUND 30 PERCENT. HEAVY RAIN MAY OCCUR
WITH ANY THUNDERSTORMS BECAUSE OF THE SLOW MOVEMENT AND
PRECIPITABLE WATER NEAR 2 INCHES. RECENT VERIFICATION FAVORS THE
WARMER TEMPERATURE GUIDANCE.

&&

.LONG TERM /THURSDAY THROUGH TUESDAY/...
THE GFS AND ECMWF SHOW RIDGING EXTENDING INTO THE AREA FROM THE
ATLANTIC DOMINATING EARLY IN THE MEDIUM-RANGE PERIOD. SUFFICIENT
MOISTURE COMBINED WITH HEATING SHOULD SUPPORT SCATTERED MAINLY
DIURNAL THUNDERSTORMS. THE MODELS HAVE COME INTO BETTER AGREEMENT
WITH THE COLD FRONT THAT WILL APPROACH THE AREA ON SUNDAY AND
MOVING INTO THE REGION LATE SUNDAY/SUNDAY NIGHT...THEN STALLING OR
DRIFTING SLOWLY SOUTHWARD THROUGH TUESDAY. WITH THE COLD FRONT IN
THE AREA SUNDAY/MONDAY...EXPECT AN INCREASED CHANCE OF SHOWERS AND
THUNDERSTORMS. THE GFS...ECMWF...AND EKD MOS HAVE POPS 20 TO 30
PERCENT EARLY INCREASING TO 30 TO 40 PERCENT BY THE END OF THE
PERIOD. ABOVE NORMAL TEMPERATURES SHOULD GRADUALLY LOWER TO NEAR
NORMAL BY THE END OF THE LONG TERM PERIOD. DUE TO ADDITIONAL CLOUD
COVER...INCREASED CHANCE OF PRECIPITATION AND SURFACE WINDS
BECOMING NE BY THE END OF THE PERIOD.

&&

.AVIATION /22Z TUESDAY THROUGH SUNDAY/...
WILL CONCENTRATE ON THE NEAR TERM WITH THE TAFS...AS THE MAIN
THREAT IS THUNDERSTORM ACTIVITY...SOME POSSIBLY SEVERE...IN THE
NEAR TERM. WILL EXPECT THUNDERSTORM ACTIVITY TO GRADUALLY
DISSIPATE LATER THIS EVENING. SOME FOG POSSIBLE LATE TONIGHT INTO
EARLY WEDNESDAY MORNING DUE TO RAIN COOLED AIR AND LIGHT
WINDS...DEPENDING ON EXTENT OF ANY LINGERING CLOUD COVER. WILL
HAVE MORE CONFIDENCE ON FOG THREAT LATER THIS EVENING. SCATTERED
THUNDERSTORMS EXPECTED AGAIN WEDNESDAY AFTERNOO AND EVENING.

EXTENDED AVIATION OUTLOOK...RESTRICTIONS POSSIBLE IN LATE NIGHT
AND EARLY MORNING STRATUS AND FOG. SCATTERED MAINLY AFTERNOON
SHOWERS AND THUNDERSTORMS THROUGH FRIDAY.

&&

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

$$





USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.