953
FXUS64 KLIX 302318
AFDLIX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
618 PM CDT WED SEP 30 2026
..NEW UPDATE, AVIATION
KEY MESSAGES
UPDATED AT 613 PM CDT WED SEP 30 2026
- SCATTERED SHOWERS AND A FEW STORMS WILL RETURN TO THE AREA
THURSDAY AFTERNOON. ONE OR TWO STORMS COULD BECOME STRONG,
PRODUCING GUSTY WINDS, FREQUENT LIGHTNING AND BRIEF PERIODS OF
HEAVY RAINFALL.
- WIDESPREAD RAIN AND EMBEDDED THUNDERSTORMS WILL AFFECT THE AREA
FRIDAY THROUGH AT LEAST SUNDAY. WHILE SPECIFIC RAINFALL TOTALS
ARE STILL UNCERTAIN, HEAVY RAIN AND AT LEAST LOCALIZED FLASH
FLOODING WILL BE A THREAT. RESIDENTS SHOULD CONTINUE TO MONITOR
THE FORECAST FOR UPDATES REGARDING THIS THREAT.
UPDATE
ISSUED AT 613 PM CDT WED SEP 30 2026
MARINE FORECAST WAS UPDATED EARLIER TO ADD SMALL CRAFT EXERCISE
CAUTION HEADLINES FOR THE OPEN GULF WATERS AND MOST BAYS AND
SOUNDS OVERNIGHT TONIGHT. SOME OR ALL OF THESE WILL PROBABLY NEED
EXTENDED THROUGH TOMORROW, BUT WILL ASSESS THAT LATER THIS
EVENING.
SHORT TERM
(NOW THROUGH THURSDAY)
ISSUED AT 120 PM CDT WED SEP 30 2026
LOW LEVEL RETURN FLOW IS BECOMING MORE ESTABLISHED ACROSS THE
AREA WITH WINDS NOW SOLIDLY OUT OF THE SOUTHEAST. DEWPOINTS
ACROSS THE SOUTHERN HALF OF THE AREA HAVE MOSTLY RECOVERED INTO
THE LOW TO MID 70S BUT MORE INTERIOR AREAS ARE STILL IN THE UPPER
60S. EXPECT A CONTINUED GRADUAL INCREASE IN LOW LEVEL MOISTURE
THROUGH TONIGHT.
WE SHOULD SEE SLIGHTLY FASTER ATMOSPHERIC MOISTURE RECOVERY
TOMORROW (THURSDAY) AS THE EDGE OF A DEEPER TROPICAL MOISTURE
PLUME BEGINS TO MOVE INTO THE AREA. MODEL PROFILES ARE INDICATING
PRECIPITABLE WATER (OVERALL ATMOSPHERIC MOISTURE) VALUES OF
1.6-1.8 INCHES BY TOMORROW AFTERNOON, WHICH IS AROUND THE 75TH
PERCENTILE FOR THIS TIME OF YEAR.
AS A RESULT OF THE INCREASED MOISTURE, RAIN CHANCES WILL ALSO
INCREASE TOMORROW. THE ADDED MOISTURE WILL ALLOW FOR SCATTERED
SHOWERS TO DEVELOP MAINLY DURING THE AFTERNOON HOURS AS DAYTIME
HEATING WILL BE NECESSARY TO BREAK THROUGH ANY REMAINING CAP.
THAT BEING SAID, WE CAN'T RULE OUT A COUPLE THUNDERSTORMS, AND ANY
STORMS THAT DO BREAK THROUGH THE CAP WILL BE CAPABLE OF PRODUCING
GUSTY WINDS, LIGHTNING AND AND BRIEF PERIODS OF HEAVY RAINFALL.
LONG TERM
(FRIDAY THROUGH TUESDAY)
ISSUED AT 120 PM CDT WED SEP 30 2026
MAIN WEATHER CONCERNS COME DURING THE FRIDAY THROUGH SUNDAY TIME
FRAME AND THERE HASN'T BEEN MUCH CHANGE IN THE OVERALL FORECAST
THINKING. STILL LOOKS LIKE A QUITE ACTIVE WEATHER PATTERN AS A
TROPICAL WAVE MOVES INTO THE NORTHERN GULF AND INTERACTS WITH A
SLOW-MOVING COLD FRONT. THE RESULT WILL BE WIDESPREAD RAINFALL
WITH EMBEDDED THUNDERSTORMS ACROSS THE LOCAL AREA MAINLY FROM LATE
FRIDAY THROUGH SUNDAY, WITH THE MOST INTENSE RAIN TAPERING OFF BY
MONDAY.
THE MOISTURE ASSOCIATED WITH THIS SYSTEM STILL LOOKS TO BE NEAR-
RECORD-SETTING FOR THIS TIME OF YEAR BASED ON OUR OBSERVED
SOUNDING CLIMATOLOGY BACK TO 1950 (1988 IF ONLY USING DATA FROM
THE CURRENT LAUNCH SITE). MOST GUIDANCE CONTINUES TO INDICATE
INDICATES PRECIPITABLE WATER (PW) VALUES WILL BE APPROACHING OR
EXCEEDING 2.5 INCHES ACROSS MUCH OF THE AREA BY LATE FRIDAY WITH
SIMILAR VALUES SATURDAY AND SUNDAY. PW VALUES LIKE THESE ARE WELL
ABOVE THE 90TH PERCENTILE AND NEARING THE DAILY MAXIMUM OBSERVED
VALUES FOR THE OCT 2-4 TIME FRAME. FOR THE CLIMATE DATA
ENTHUSIASTS OUT THERE, THE CURRENT DAILY RECORDS ARE 2.54, 2.53
AND 2.72 INCHES, RESPECTIVELY, WITH THE RECORDS ON OCT 3 AND 4
BOTH ASSOCIATED WITH 2002'S HURRICANE LILI. THE RECORD ON OCT 2
MAY BE ASSOCIATED WITH REMNANTS OF 1965'S TS DEBBIE WHICH MADE
LANDFALL IN SE LA ON SEP 30, BUT THAT ONE IS LESS CONCLUSIVE
WITHOUT MORE THOROUGH DIGGING.
THE AMPLE MOISTURE WILL RESULT IN PRIME CONDITIONS FOR EFFICIENT
RAINFALL PROCESSES AND THUS HIGH RAINFALL RATES ARE LIKELY.
INSTANTANEOUS RATES OF OVER 4 INCHES PER HOUR WILL BE POSSIBLE
IN THE HEAVIEST STORMS, WHICH CAN EASILY OVERWHELM DRAINAGE
CAPACITY IN URBAN AND OTHER POOR DRAINAGE AREAS, EVEN OVER SHORT
DURATIONS. CURRENTLY WE CONTINUE TO HIGHLIGHT A MARGINAL RISK
(LEVEL 1 OF 4) OF EXCESSIVE RAINFALL/FLASH FLOODING FRIDAY
FOLLOWED BY SLIGHT RISKS (LEVEL 2 OF 4) SATURDAY AND SUNDAY. THESE
THREAT LEVELS COULD CHANGE AS THE SPECIFICS OF THE EVENT BECOME
CLEARER AND UNFOLD.
CURRENT STORM TOTALS FOR THE FRIDAY THROUGH SUNDAY PERIOD ARE
STILL FORECAST IN THE 3-6" RANGE, WITH HIGHER CONFIDENCE IN THE
THREAT ACROSS ROUGHLY THE SOUTHEASTERN HALF OF THE AREA. THERE
WILL LIKELY BE POCKETS OF HIGHER TOTALS AND THE HIGHER END
POTENTIAL CONTINUES TO BE TOUGH TO NAIL DOWN GIVEN THE MULTI-DAY
LEAD TIME.
THE GOOD NEWS IS THAT RIVERS ACROSS THE REGION ARE CURRENTLY LOW
AND THUS WATER STORAGE CAPACITY IS CURRENTLY HIGH - MEANING THAT
AT LEAST FOR NOW, THIS APPEARS TO BE MORE OF A FLASH FLOOD
CONCERN THAN A SIGNIFICANT RIVER FLOOD CONCERN.
BY MONDAY AND TUESDAY, THE FRONT SHOULD SINK A LITTLE FARTHER
SOUTH IN RESPONSE TO ANOTHER UPPER TROUGH MOVING THROUGH THE LOWER
MISSISSIPPI VALLEY. WHILE THE FRONT DOESN'T CURRENTLY LOOK TO PUSH
FAR ENOUGH SOUTH TO COMPLETELY DRY OUT THE LOCAL AREA, IT SHOULD
SHIFT THE AXIS OF ANY REMAINING HEAVY RAIN INTO THE NORTHERN GULF.
AVIATION
(00Z TAFS)
ISSUED AT 613 PM CDT WED SEP 30 2026
GENERALLY VFR CONDITIONS OVERNIGHT, ALTHOUGH KMCB MAY SEE SOME
BRIEF VISIBILITY RESTRICTIONS AROUND SUNRISE THURSDAY. ISOLATED
SHRA/TSRA POSSIBLE AT MOST TERMINALS THURSDAY AFTERNOON, WITH
POTENTIAL MVFR IMPACTS. FOR NOW, WILL USE PROB30 -SHRA, BUT
THREAT OF TSRA IS NON-ZERO. LOWEST THREAT WILL BE AT KMCB, AND
WILL NOT INCLUDE THERE. MOST CONVECTION SHOULD DISSIPATE PRIOR TO
00Z FRIDAY.
MARINE
ISSUED AT 120 PM CDT WED SEP 30 2026
A TIGHTENING PRESSURE GRADIENT WILL ALLOW WINDS TO STRENGTHEN TO 15
TO 20 KNOTS BY THURSDAY OR THURSDAY NIGHT. SHOWERS AND SOME
THUNDERSTORMS WILL BEGIN TO INCREASE IN COVERAGE THURSDAY AND
ESPECIALLY FRIDAY THROUGH THE WEEKEND AS A TROPICAL WAVE MOVES
THROUGH THE NORTHERN GULF AND INTERACTS WITH AN APPROACHING WEAK
COLD FRONT.
LIX WATCHES/WARNINGS/ADVISORIES
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
SHORT TERM...DM
LONG TERM....DM
AVIATION/UPDATE...RW
MARINE...DM
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page