321
FXUS62 KCAE 091655
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
1255 PM EDT SUN AUG 9 2026
WHAT HAS CHANGED
STORM CHANCES REMAIN LOW TODAY WITH ONLY ISOLATED ACTIVITY
ANTICIPATED. AVIATION DISCUSSION UPDATED FOR 18Z TAFS.
KEY MESSAGES
- 1. ISOLATED DIURNAL STORMS POSSIBLE EACH DAY THIS WEEK, WITH
DIMINISHING CHANCES MIDWEEK. A STRONG STORM CANNOT BE RULED
OUT.
- 2. INCREASING HEAT AND HUMIDITY IS EXPECTED NEXT WEEK.
DISCUSSION
- 1. ISOLATED DIURNAL STORMS POSSIBLE EACH DAY THIS WEEK, WITH
DIMINISHING CHANCES MIDWEEK. A STRONG STORM CANNOT BE RULED
OUT.
SATELLITE IMAGERY SHOWS SOME FAIR WEATHER CUMULUS DEVELOPING
ACROSS THE FORECAST AREA, BUT THUS FAR THEY AREN'T LOOKING TOO
AGITATED. THE MOST AGITATED CUMULUS THUS FAR ARE FROM THE UPPER
CSRA INTO THE PEEDEE. HI- RES GUIDANCE FROM THIS MORNING DOES
SUGGEST SOME ISOLATED STORMS DEVELOPING THIS AFTERNOON, BUT MOST
OF THE ACTIVITY IS EXPECTED TO REMAIN NEAR THE COAST AND IN THE
MOUNTAINS. SBCAPE VALUES RANGE FROM 2200 J/KG TO OVER 3000 J/KG
PER THE SPC MESOANALYSIS PAGE, WHICH COULD RESULT IN A STRONGER
STORM AS WE HEAD INTO THE AFTERNOON. HOWEVER, THE SEVERE THREAT
IS LOW.
SOUTHERLY TO SOUTHEASTERLY NEAR SURFACE FLOW IS EXPECTED TO
CONTINUE TODAY AND INTO EARLY NEXT WEEK, BEFORE BECOMING A BIT
MORE SOUTHWESTERLY TO WESTERLY LATE IN THE WEEK. OVERALL, WITH
THE REGION REMAINING BETWEEN THE UPPER RIDGE OVER THE WESTERN US
AND THE STRONG AREA OF HIGH PRESSURE OFF THE EAST COAST,
SEASONABLE MOISTURE SHOULD PERSIST THROUGH THE FORECAST PERIOD
WITH SURFACE DEWPOINTS LIKELY REMAINING IN THE LOW TO MID 70S
MUCH OF THE FORECAST PERIOD (AS WELL AS PWAT'S NEAR TO JUST
BELOW 2"). THIS MOISTURE COMBINED WITH STRONG HEATING SHOULD
BRING SBCAPE VALUES GREATER THAN 2000 J/KG MOST DAYS BUT WITH
LACKING UPPER KINEMATICS, CREATING AN ENVIRONMENT CONDUCIVE FOR
SPOTTY TO ISOLATED PULSE CONVECTION EACH AFTERNOON THROUGH THE
THE FIRST PART OF THE WEEK, THOUGH THE LATEST NBM GUIDANCE
CONTINUES TO COME IN DRIER THAN PREVIOUS RUNS FOR THE MIDWEEK
TIMEFRAME. AS IS TYPICAL THIS TIME OF THE YEAR, A STRONG STORM
OR TWO CANNOT BE RULED OUT WITH THE RISK OF STRONG DOWNBURST
WINDS, BUT WIDESPREAD SEVERE WEATHER IS UNLIKELY. A BIT MORE
UNCERTAINTY IN TERMS OF PRECIP CHANCES ENTERS LATE THIS WEEK
INTO THE WEEKEND. THIS IS DRIVEN BY GREATER SPREAD AMONGST
GLOBAL DETERMINISTIC AND ENSEMBLE GUIDANCE WITH THE STRENGTH OF
A SHORTWAVE MOVING OUT OF THE NORTHERN GREAT LAKES AND THUS IT'S
ABILITY TO PUSH A SURFACE FRONT NEAR THE REGION. A MORE
AMPLIFIED SOLUTION COULD BRING INCREASED RAIN CHANCES/COVERAGE,
BUT DETAILS STILL NEED TO BE SORTED OUT, WHILE A LESS AMPLIFIED
SOLUTION WOULD LEAN MORE TO LOWER, MORE TYPICAL SUMMER TIME
SPOTTY STORMS.
- 2. INCREASING HEAT AND HUMIDITY IS EXPECTED NEXT WEEK.
THE 500MB HEIGHTS ARE EXPECTED TO GRADUALLY RISE THROUGH THE
WEEK, PEAKING NEAR THE NAEFS 90TH PERCENTILE BY THE LATE WEEK.
AS THIS OCCURS, 850MB TEMPERATURES CURRENTLY NEAR 18C SHOULD
RISE TO BETWEEN 20-23C BY THE MID WEEK. WITH THESE WARMING LOW
LEVEL TEMPERATURES, RISING MID LEVEL HEIGHTS, AND THE EXPECTED
SPOTTY NATURE OF AFTERNOON CONVECTION, HIGH TEMPERATURES ARE
PROGGED TO PEAK IN THE MID TO UPPER 90S TUESDAY ONWARD. DUE TO
THE UNCERTAINTY IN POTENTIAL TROUGHING BY THIS WEEKEND DISCUSSED
IN KEY MESSAGE #1, LARGER NBM IQR SPREADS EXIST, BUT NEAR
NORMAL TO JUST ABOVE NORMAL TEMPERATURES STILL SEEM LIKELY.
SURFACE DEWPOINTS REMAINING IN THE LOW TO MID 70S THROUGH THE
PERIOD BRING INCREASED CONFIDENCE IN HEAT INDICES RISING BACK
ABOVE 100F WITH LREF PROBABILITIES REACHING ABOVE 70% BY TUESDAY
WITH PROBABILITIES FOR INDICES ABOVE 105F BETWEEN 30-50%
THURSDAY AND FRIDAY. OVERALL, CONFIDENCE IN REACHING HEAT
ADVISORY CRITERIA IS LOW, BUT SPOTS OF 105-108F COULD BE
POSSIBLE MAINLY BETWEEN WEDNESDAY AND FRIDAY SO BE PREPARED FOR
RETURNING HOT/HUMID CONDITIONS THIS WEEK.
AVIATION /18Z SUNDAY THROUGH THURSDAY/
VFR LIKELY SUNDAY AFTERNOON INTO EARLY MONDAY, OUTSIDE OF SOME
ISOLATED STORMS. SOME MORNING STRATUS-FOG POSSIBLE MONDAY, BUT
LESS WIDESPREAD THAN PREVIOUS DAYS.
TYPICAL SUMMER CONDITIONS OUT THERE THIS AFTERNOON WITH A BROAD
CU FIELD AROUND 3500 FEET. CONVECTION SHOULD REMAIN ACROSS THE
UPSTATE AND COASTAL PLAIN THROUGH LATE AFTERNOON, WITH SOME
INCREASING CHANCES FOR STORMS AT THE TAF SITES. CONFIDENCE IS
ONLY HIGH ENOUGH FOR A PROB30 TAF MENTION AT THIS TIME HOWEVER.
MORNING STRATUS-FOG MONDAY LOOKS LESS LIKELY THAN THE LAST FEW
MORNINGS ESPECIALLY WITH A LACK OF WIDESPREAD RAINFALL.
EXTENDED AVIATION OUTLOOK...A SEASONAL PATTERN OF EARLY MORNING
RESTRICTIONS AND DIURNAL THUNDERSTORMS IS LIKELY THROUGH MUCH
OF THE EXTENDED.
CAE WATCHES/WARNINGS/ADVISORIES
SC...NONE.
GA...NONE.
DISCUSSION...29
AVIATION...42
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page