692
FXUS62 KCAE 041756
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
156 PM EDT FRI SEP 4 2026
WHAT HAS CHANGED
A HEAT ADVISORY REMAINS IN EFFECT THROUGH 8 PM THIS EVENING FOR
LANCASTER AND CHESTERFIELD COUNTIES. A HEAT ADVISORY HAS BEEN
ISSUED FOR TOMORROW FOR THE ENTIRE AREA. AVIATION DISCUSSION
UPDATED FOR 18Z TAF ISSUANCE.
KEY MESSAGES
- 1. HEAT INDEX VALUES UP TO 110 SATURDAY ELEVATING THE RISK OF
HEAT RELATED ILLNESSES.
- 2. HEAT ADVISORY CONTINUES FOR LANCASTER AND CHESTERFIELD
COUNTIES THROUGH 8 PM TODAY.
- 3. SEVERE STORMS POSSIBLE SATURDAY AFTERNOON OR EVENING.
DISCUSSION
KEY MESSAGE 1. HEAT INDEX VALUES UP TO 110 SATURDAY ELEVATING
THE RISK OF HEAT RELATED ILLNESSES.
THE CENTER OF THE UPPER RIDGE SHIFTS WEST ON SATURDAY. WEAK
DOWNSLOPE WINDS AND INCREASING MOISTURE AHEAD OF A COLD FRONT
WILL PUSH AFTERNOON TEMPERATURES INTO THE UPPER 90S TO NEAR 100
DEGREES AND HEAT INDEX VALUES TO NEAR 110. THERE WILL ALSO BE A
GREATER VULNERABILITY TO HEAT RELATED ILLNESS DUE THE UPTICK IN
OUTDOOR ACTIVITIES THIS SATURDAY. A HEAT ADVISORY HAS BEEN
ISSUES FOR THE ENTIRE FORECAST AREA.
THERE IS SOME POTENTIAL FOR THUNDERSTORMS, ESPECIALLY IN THE
NORTHERN FA LATE SATURDAY AFTERNOON AND EVENING. BUT WE BELIEVE
THAT THE LATER TIMING OF THE STORMS WILL STILL ALLOW HEAT INDEX
VALUES TO EXCEED ADVISORY THRESHOLDS THROUGH THE BULK OF THE
AFTERNOON.
KEY MESSAGE 2. HEAT ADVISORY CONTINUES FOR LANCASTER AND
CHESTERFIELD COUNTIES THROUGH 8 PM TODAY.
TEMPERATURES WILL RISE IN THE MID TO UPPER 90S THIS AFTERNOON.
DEWPOINTS HAVE MIXED INTO THE LOW 70S, BUT A FEW LOCATIONS IN
THE NORTHERN MIDLANDS COULD TICK UP INTO THE MID 70S. OVERALL,
THIS SHOULD YIELD HEAT INDICES BETWEEN 105-108. A FEW AREAS NEAR
CHESTERFIELD AND LANCASTER COUNTIES COULD BRIEFLY REACH HEAT
ADVISORY CRITERIA AND DUE TO THIS, A HEAT ADVISORY WILL REMAIN
IN EFFECT UNTIL 8PM THIS EVENING FOR THESE COUNTIES.
KEY MESSAGE 3. SEVERE STORMS POSSIBLE SATURDAY AFTERNOON OR
EVENING.
AS RIDGING SHIFTS WEST, WE WILL SEE SHORTWAVE ENERGY DIG INTO
THE MID ATLANTIC STATES ON SATURDAY AFTERNOON AND EVENING. A
COLD FRONT WELL TO OUR NORTH WILL BE THE FOCUS FOR CONVECTIVE
INITIATION. AS STORMS DEVELOP AND MOVE SOUTH AND EAST DURING THE
DAY THEY WILL ENCOUNTER VERY STEEP LAPSE RATES WHICH WOULD SUPPORT
DAMAGING WINDS IN SOME OF THE STRONGER STORMS. THE OVERALL
LIMITING FACTORS FOR SEVERE WEATHER INTO SC WILL BE THE LIMITED
MOISTURE AVAILABLE AND THE FACT THAT THE STRONGER DYNAMICS
SHOULD REMAIN TO OUR NORTH. WITH PWAT VALUES ONLY 1.6 TO 1.8
INCHES WE MAY ONLY SEE SCATTERED THUNDERSTORMS THAT DO NOT
DEVELOP INTO AN MCS. HOWEVER, EVEN IF THE STRONGER STORMS DO
REMAIN TO OUR NORTH, AN OUTFLOW BOUNDARY COULD STILL PUSH INTO
THE NORTHERN FA IN THE EVENING. THIS COULD SPARK AT LEAST
SCATTERED CONVECTION THROUGH THE EVENING AND OVERNIGHT AS IT
PROGRESSES SOUTHWARD THROUGH THE FORECAST AREA.
WITH A SURFACE BOUNDARY OVER THE REGION ON SUNDAY WE CAN EXPECT
AT LEAST A CHANCE OF SHOWERS AND THUNDERSTORMS AS AN UPPER
LEVEL SHORTWAVE CROSSES INTO THE FORECAST AREA. WITH A DEEPER
TROUGH AND HIGHER ATMOSPHERIC MOISTURE WE WOULD EXPECT SCATTERED
TO NUMEROUS THUNDERSTORMS SUNDAY AFTERNOON AND EVENING. CLOUD
COVER COULD ULTIMATELY HINDER POTENTIAL INSTABILITY AND LOWERS
THE THREAT OF SEVERE WEATHER. THAT SAID A FEW STORMS MAY STILL
BECOME SEVERE, ESPECIALLY IF CLOUD COVER STARTS BREAKING EARLIER
THAN EXPECTED.
AVIATION /18Z FRIDAY THROUGH WEDNESDAY/
MAINLY VFR CONDITIONS THROUGH THE TAF PERIOD, WITH SOME FOG
POSSIBLE NEAR DAYBREAK.
A CUMULUS FIELD IS BEING NOTED ACROSS THE FORECAST AREA THIS
AFTERNOON WITH BASES AROUND THE 4K-5K FT RANGE. EXPECT THE
CUMULUS FIELD TO CONTINUE THROUGH SUNDOWN. SOUTHERLY WINDS IN
THE 5-10 KT RANGE FOR THE AFTERNOON AS WELL BEFORE BECOMING
LIGHT AND VARIABLE TO CALM OVERNIGHT. THERE IS POTENTIAL FOR FOG
AT THE TERMINALS AROUND DAYBREAK. AS OF NOW, THE HIGHEST
CONFIDENCE FOR REDUCED VIS IS AT AGS, SO HAVE INCLUDED IT IN THE
TAF THERE. LEAVING IT OUT OF THE OTHER TERMINALS FOR THE TIME
BEING; HOWEVER.
EXTENDED AVIATION OUTLOOK...CHANCES FOR RESTRICTIONS AND
THUNDERSTORMS INCREASE SATURDAY AFTERNOON AND SUNDAY AS A COLD
FRONT APPROACHES.
CAE WATCHES/WARNINGS/ADVISORIES
SC...HEAT ADVISORY FROM 11 AM TO 8 PM EDT SATURDAY FOR SCZ016-018-
020>022-025>031-035-037-038-041-115-116-135>137.
HEAT ADVISORY UNTIL 8 PM EDT THIS EVENING FOR SCZ016-115-116.
GA...HEAT ADVISORY FROM 11 AM TO 8 PM EDT SATURDAY FOR GAZ040-
063>065-077.
DISCUSSION...CJR
AVIATION...29
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page