806
FXUS62 KCAE 190006
AFDCAE
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE COLUMBIA SC
806 PM EDT SAT JUL 18 2026
WHAT HAS CHANGED
HEAT ADVISORY ALLOWED TO EXPIRE. AVIATION DISCUSSION UPDATED
FOR 00Z TAFS.
KEY MESSAGES
- 1. ISOLATED CONVECTION POSSIBLE OVER THE COMING HOURS, BUT
SEVERE THREAT IS DIMINISHING.
- 2. MORE THUNDERSTORM CHANCES SUNDAY INTO MONDAY WITH POSSIBLE
SEVERE THUNDERSTORMS. ANOTHER CHANCE FOR STRONG CONVECTION
POSSIBLE DURING THE MIDWEEK.
DISCUSSION
KEY MESSAGE 1: ISOLATED CONVECTION POSSIBLE OVER THE COMING HOURS,
BUT SEVERE THREAT IS DIMINISHING.
HEAT INDICES ARE GRADUALLY FALLING THIS EVENING AND SHOULD FALL
UNDER 100F IN THE NEXT HOUR OR TWO. DUE TO THIS, THE HEAT
ADVISORY IS NOW EXPIRED. A COUPLE ISOLATED STORMS HAVE POPPED
UP IN THE MIDLANDS OVER THE LAST HOUR, BUT OUTSIDE OF THIS,
MID-LEVEL CAPPING HAS SEEMED TO KEEP INITIATION LARGELY
SUPPRESSED AS THE CU FIELD THROUGH THE AFTERNOON AND INTO THIS
EVENING HAS BEEN FAIRLY LOW TOPPED. PWAT'S HAVE ALSO BEEN A BIT
LOWER AS A POCKET OF DRIER MID-LEVEL AIR SEEN IN WV IMAGERY HAS
PUSHED INTO THE REGION. CANNOT RULE OUT A FEW MORE STORMS AS THE
SEA BREEZE PUSHES FURTHER INLAND, BUT WITH THE LOSS OF HEATING,
THE OVERALL SEVERE RISK WITH ANY STORM SHOULD DIMINISH.
KEY MESSAGE 2: MORE THUNDERSTORM CHANCES SUNDAY INTO MONDAY
WITH POSSIBLE SEVERE THUNDERSTORMS. ANOTHER CHANCE FOR STRONG
CONVECTION POSSIBLE DURING THE MIDWEEK.
AS HAS BEEN DISCUSSED, A DEEPENING SHORTWAVE IS PROGGED TO MOVE
INTO THE MID-ATLANTIC THROUGH THE DAY SUNDAY, DRAGGING A
SURFACE FRONT THAT COULD NEAR THE PEE DEE SUNDAY NIGHT. ENHANCED
MOISTURE ADVECTION IS SHOWN ACROSS GUIDANCE AHEAD OF THESE
FEATURES WITH PWAT'S REACHING ABOVE 2", PARTLY THANKS TO GULF
MOISTURE BEING TRANSPORTED NORTHWARD ON THE EASTERN PERIPHERY OF
A DEVELOPING WEAK TROPICAL DISTURBANCE IN THE NORTHEASTERN
GULF. OVERALL, THE ENVIRONMENT IS NOT EXPECTED TO BE ALL THAT
DIFFERENT FROM THE LAST COUPLE OF DAYS, FAVORING A DAMAGING WIND
RISK FROM PRECIP-LOADED DOWNDRAFTS. THE MAIN DIFFERENCE IS
MARGINAL UPPER SUPPORT SHOULD BRING INCREASED COVERAGE AND
EFFECTIVE SHEAR VALUES NEAR 10-15 KTS, ESPECIALLY TOWARD THE PEE
DEE, WHICH COULD AID IN BETTER ORGANIZATION OF A FEW CLUSTERS.
THIS HAS RESULTED IN MOST OF THE FA REMAINING IN A MARGINAL RISK
FOR SEVERE WEATHER, BUT A SLIGHT RISK (LEVEL 2 OUT OF 5) STILL
SCRAPES THE PEE DEE WITH THE GREATER SHEAR HERE. THE FRONTAL
BOUNDARY IS EXPECTED TO REMAIN NEAR THE PEE DEE INTO MONDAY WITH
WEAK SHORTWAVE ENERGY PASSING THROUGH THE REGION, BRINGING
ANOTHER DAY WITH INCREASED AFTERNOON CONVECTIVE COVERAGE AND THE
CHANCE FOR A COUPLE STRONG TO MARGINALLY SEVERE STORMS.
NHC NOW HAS A 40% OUTLOOK AREA AS THE EC ENSEMBLE AND GOOGLE
DEEPMIND HAVE TRENDED MORE TOWARDS THE WEAK TROPICAL DISTURBANCE
MEANDERING THROUGH THE NORTHEASTERN GULF EARLY IN THE WEEK
BEFORE SLOWLY DRIFTING WESTWARD INTO THE MID WEEK. THIS SHOULD
STILL ALLOW DEEP MOISTURE TO ADVECT INTO THE REGION FROM THE
SOUTH, BUT BOTH ENSEMBLE AND DETERMINISTIC GUIDANCE HAVE
DISPLAYED INCREASED CONFIDENCE THAT AN EVEN SHARPER SHORTWAVE
SHOULD DIG INTO THE EASTERN CONUS DURING THE MID-WEEK, POSSIBLY
DRAGGING ANOTHER FRONTAL BOUNDARY NEAR THE FA. ENHANCED
KINEMATICS COUPLED WITH SEASONABLE TO STRONG INSTABILITY COULD
BRING ANOTHER CHANCE FOR STRONGER CONVECTION DURING THE MIDWEEK
AS HIGHLIGHTED IN CSU/CIPS/NCAR MACHINE LEARNING AND AI
GUIDANCE. TIMING DIFFERENCE STILL NEED TO BE SORTED OUT ACROSS
DETERMINISTIC GUIDANCE, BUT THE PATTERN SEEMS FAVORABLE FOR
POTENTIAL SEVERE WEATHER AGAIN.
AVIATION /00Z SUNDAY THROUGH THURSDAY/
VFR CONDITIONS ARE EXPECTED TO PREVAIL FOR THE FORECAST PERIOD
OUTSIDE OF CONVECTION.
LITTLE CONVECTION THIS EVENING AS IT HAS REMAINED TO THE
NORTHWEST SO FAR, ALTHOUGH THERE IS ISOLATED STORMS ALONG A
BOUNDARY WEST OF CAE SO INCLUDED SOME VCSH FOR A COUPLE OF HOURS
TO START THE FORECAST. CONFIDENCE IS LOW IN CONVECTION MOVING
INTO THE TERMINALS LATER THIS EVENING SO WILL AMEND AS NEEDED
FOR ANY STORMS THAT MAY REACH THE MIDLANDS. LIGHT SOUTHERLY
WINDS OVERNIGHT WILL PICK UP TO AROUND 10 KNOTS AND BECOME GUSTY
AFTER 15Z SUNDAY AHEAD OF AN APPROACHING UPPER TROUGH AND
FRONTAL BOUNDARY. LATE AFTERNOON STORMS POSSIBLE AGAIN MOVING
DOWN FROM THE UPSTATE SO INCLUDED A PROB30 GROUP FOR THAT
POSSIBILITY. CANNOT TOTALLY RULE OUT SOME BRIEF PREDAWN
FOG/STRATUS BUT CONFIDENCE IS TOO LOW TO INCLUDE AT THIS TIME
AND NO GUIDANCE IS SUPPORTING RESTRICTIONS.
EXTENDED AVIATION OUTLOOK...POTENTIAL FOR RESTRICTIONS FROM SHOWERS
AND THUNDERSTORMS CONTINUES INTO NEXT WEEK.
CAE WATCHES/WARNINGS/ADVISORIES
SC...NONE.
GA...NONE.
DISCUSSION...DH
AVIATION...23
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page