976
FXUS64 KLIX 302346
AFDLIX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
646 PM CDT THU APR 30 2026
..NEW UPDATE, AVIATION
KEY MESSAGES
UPDATED AT 630 PM CDT THU APR 30 2026
- HEAVY RAINFALL AND INCREASED RISK OF FLASH FLOODING WILL IMPACT
MUCH OF THE REGION FRIDAY NIGHT.
- THE THREAT FOR THUNDERSTORMS, SOME POSSIBLY STRONG TO SEVERE
WILL CONTINUE THROUGH FRIDAY NIGHT.
- COOLER THAN NORMAL HIGH TEMPERATURES ARE EXPECTED FRIDAY THROUGH
MONDAY.
UPDATE
ISSUED AT 630 PM CDT THU APR 30 2026
STRONGEST CONVECTION NOW SINKING SOUTHEASTWARD TO THE SOUTH OF
INTERSTATE 10 AND SOUTH OF NEW ORLEANS. STILL LIGHT TO MODERATE
RAIN OVER MUCH OF THE AREA AWAY FROM THE CLUSTER OF THUNDERSTORMS,
BUT RADAR INDICATES THAT THERE IS A BACK EDGE TO THIS RAIN AREA
NEAR BATON ROUGE. THERE IS STILL MORE PRECIPITATION OVER NORTHWEST
LOUISIANA AND EASTERN TEXAS, SO WE WON'T DRY OUT THE OVERNIGHT
FORECAST COMPLETELY BEHIND THIS BATCH.
WILL PROBABLY DO AN UPDATE IN THE NEXT HOUR OR TWO AS WE SEE HOW
MUCH OF THE CURRENT PRECIPITATION WE LOSE WITH THE LOSS OF SURFACE
HEATING. ANY UPDATES WILL ONLY COVER THE OVERNIGHT HOURS TONIGHT,
PRIOR TO THE MAIN PACKAGE ISSUANCE AROUND 1 AM CDT.
SHORT TERM
(NOW THROUGH SATURDAY NIGHT)
ISSUED AT 1225 PM CDT THU APR 30 2026
AN EXCELLENT SETUP FOR LOCALLY HEAVY RAINFALL TO DEVELOP WILL
REMAIN IN PLACE THROUGH THE ENTIRE SHORT TERM PERIOD. A STALLED
FRONTAL BOUNDARY WILL REMAIN IN PLACE ALONG THE I-10 CORRIDOR
PWATS WILL BE NEAR THE DAILY MAXIMUM THROUGH TOMORROW NIGHT. AT
THE SAME TIME, FAVORABLE UPPER LEVEL JET DYNAMICS WILL SUPPORT
CONTINUED DEEP LAYER FORCING OVER THE AREA. IN THE LOW TO MID-
LEVELS A REGION OF ENHANCED BAROCLINICITY BENEATH THE UPPER LEVEL JET
COUPLET WILL ALLOW A LOW PRESSURE TO FORM ALONG THE STALLED FRONT
BY TOMORROW MORNING. THIS LOW WILL TRACK TO THE EAST AND HELP TO
INCREASE BOTH ISENTROPIC FORCING BEHIND THE FRONT AND MOISTURE
CONVERGENCE ALONG THE FRONTAL BOUNDARY. MEAN STORM RELATIVE FLOW
WILL BE LARGELY PARALLEL THE FRONTAL BOUNDARY, SO ANY STORMS THAT
FORM WILL TRACK ALONG THE BOUNDARY. THIS WILL ALLOW FOR A GREATLY
INCREASED RISK OF TRAINING THUNDERSTORMS TO FORM AS EARLY AS LATE
FRIDAY AFTERNOON, BUT MORE LIKELY ON FRIDAY NIGHT WHEN OUR FLASH
FLOOD THREAT PEAKS. RAINFALL TOTALS OF 2 TO 4 INCHES ARE
GENERALLY EXPECTED OVER THE NEXT 2 DAYS, BUT LOCALIZED AREAS OF 4
TO 8 INCHES CAN BE EXPECTED. EVEN WITH THE LATEST HIGH RESOLUTION
MODELING, THE AXIS OF HEAVIEST RAINFALL WILL BE HIGHLY DEPENDENT
ON EXACTLY WHERE THE STATIONARY BOUNDARY AND GREATEST MOISTURE
CONVERGENCE DEVELOPS. THE THREAT LOOKS TO BE HIGHEST NORTH OF I-10
AT THIS TIME, BUT IF THE BOUNDARY SINKS FURTHER SOUTH THAN
EXPECTED, THAT HEAVY RAIN AXIS COULD SHIFT INTO METRO NEW ORLEANS
AND THE RIVER PARISHES. WE WILL NEED TO MONITOR THE POSITIONING OF
THE FRONT CAREFULLY AS WE MOVE INTO TOMORROW. WE HAVE ALSO OPTED
TO HOLD OFF ON ISSUING A FLOOD WATCH DUE TO THE UNCERTAINTY IN
WHERE THE HEAVIEST RAINFALL WILL OCCUR.
LOOKING BEYOND THE HEAVY RAIN CONCERNS, AMPLE INSTABILITY AND
SPEED SHEAR WILL ALSO BE IN PLACE TO THE SOUTH OF THE STALLED
FRONTAL BOUNDARY THROUGH FRIDAY NIGHT. 0-6KM SHEAR WILL REMAIN ON
THE ORDER OF 50 TO 60 KNOTS AND AREAS SOUTH OF THE FRONT WILL SEE
MLCAPE VALUES OF 1000 TO 1500 J/KG EACH AFTERNOON. THESE VALUES
COMBINED WITH THE DEEP LAYER FORCING OVER THE REGION WILL SUPPORT
A RISK OF ISOLATED SEVERE THUNDERSTORM DEVELOPMENT BOTH THIS
AFTERNOON AND AGAIN FRIDAY AFTERNOON FOR COASTAL LOUISIANA AND THE
OFFSHORE WATERS. ALTHOUGH DIRECTIONAL SHEAR WILL BE MORE LIMITED
AT AROUND 100 TO 150 M2/S2 IN THE LOWEST 3KM, SOME WEAK
MESOCYCLONIC DEVELOPMENT IN THE UPDRAFT WILL OCCUR WITH ANY
SEVERE STORMS. TORNADOES ARE UNLIKELY TO OCCUR, BUT THESE WEAKLY
ROTATING UPDRAFTS WILL SUPPORT A LARGER HAIL FORMATION AS
RESIDENCE TIME INCREASES IN THESE LONGER LASTING AND DEEPER
UPDRAFT CORES. AS THE CORES ALOFT FINALLY EXCEED THE BUOYANT
FORCING WITH THE UPDRAFT, THEY WILL COLLAPSE AND PRODUCE PERIODS
OF SEVERE HAIL AND STRONG DAMAGING WINDS IN COASTAL LOUISIANA AND
OFFSHORE.
TEMPERATURES WILL BE MUCH COOLER THAN PREVIOUS DAYS DUE TO THE
BOUNDARY BEING STALLED OVER THE AREA. PERSISTENT CLOUD COVER AND
PERIODS OF RAIN WILL COMBINE WITH FAIRLY STRONG COLD AIR ADVECTION
BEHIND THE FRONT TO KEEP TEMPERATURES IN THE 60S AND LOWER 70S
NORTH OF THE FRONT. SOUTH OF THE FRONT, TEMPERATURES WILL REMAIN
WARM WITH HIGHS CLIMBING INTO THE UPPER 70S AND LOWER 80S BOTH
TODAY AND TOMORROW. A VERY SMALL DIURNAL RANGE IS EXPECTED TONIGHT
AND DEWPOINTS REMAIN VERY HIGH WITH READINGS ONLY COOLING INTO THE
UPPER 50S AND LOWER 60S NORTH OF THE FRONT AND THE UPPER 60S SOUTH
OF THE FRONT. BY TOMORROW NIGHT, TEMPERATURES AND DEWPOINTS WILL
BEGIN TO DROP QUICKLY AS THE FRONT PUSHES OFFSHORE LATE IN THE
NIGHT. LOWS SHOULD DROP INTO THE LOW TO MID 50S BY DAYBREAK ON
SATURDAY.
A DEEP NORTHERN STREAM LONGWAVE TROUGH AXIS WILL PASS THROUGH THE
AREA ON SATURDAY AND THIS WILL HELP TO FULLY DRIVE ALL OF THE RAIN
OUT OF THE AREA AS A COLD FRONT SWEEPS OUT INTO THE CENTRAL GULF.
BREEZY AND SIGNIFICANTLY COLDER CONDITIONS WILL TAKE HOLD BY
SATURDAY AFTERNOON WITH NORTHERLY WINDS OF 15 TO 20 MPH AND
TEMPERATURES IN THE UPPER 60S AND LOWER 70S EXPECTED. THE
COMBINATION OF CLEAR SKIES AND CONTINUED COLD AIR ADVECTION INTO
THE AREA SATURDAY NIGHT WILL ALLOW LOWS TO COOL INTO THE UPPER 40S
AND LOWER 50S ACROSS MOST OF THE AREA. ONLY THE IMMEDIATE
SOUTHSHORE OF LAKE PONTCHARTRAIN AND THE IMMEDIATE COAST OF
LOUISIANA WILL SEE LOWS IN THE MID 50S DUE TO THE WARMER NEARBY
WATERS MODIFYING THE TEMPERATURES SLIGHTLY.
LONG TERM
(SUNDAY THROUGH WEDNESDAY NIGHT)
ISSUED AT 1225 PM CDT THU APR 30 2026
A BROAD AND DEEP LOW TO MID-LEVEL HIGH WILL REMAIN IN FIRM CONTROL
OF THE FORECAST AREA ON SUNDAY AND MONDAY. SKIES WILL REMAIN
LARGELY CLEAR AND HUMIDITY WILL REMAIN LOW AS THIS HIGH DOMINATES
THE REGION. TEMPERATURES WILL ALSO RUN A BIT BELOW AVERAGE WITH
HIGHS IN THE MID 70S SUNDAY AFTERNOON AND THE UPPER 70S MONDAY
AFTERNOON. LOWS WILL ALSO REMAIN COOL SUNDAY NIGHT AS CLEAR SKIES,
LOW DEWPOINTS, AND LIGHTER WINDS ALLOW TEMPERATURES TO FALL BACK
INTO THE UPPER 40S AND LOWER 50S OVER INLAND AREAS. COASTAL
LOCATIONS WILL ONCE AGAIN FALL INTO THE MID 50S.
TUESDAY AND WEDNESDAY WILL SEE THE PATTERN SHIFT ONCE MORE. A
ZONAL FLOW REGIME WILL DEVELOP IN THE UPPER LEVELS WHILE A
PERSISTENT AND DEEP LAYER ONSHORE FLOW PATTERN WILL FORM ON THE
WESTERN PERIPHERY OF A DEPARTING HIGH IN THE LOW TO MID-LEVELS.
THIS ONSHORE FLOW REGIME WILL ALLOW FOR GULF MOISTURE AND WARMTH
TO BEGIN FEEDING BACK INTO THE AREA. TUESDAY WILL REMAIN DRY AS
THE MID-LEVELS REMAIN DRY AND A CAPPING INVERSION LINGERS, BUT AS
MOISTURE DEEPENS ON WEDNESDAY A PASSING SOUTHERN STREAM VORT MAX
WILL ALLOW FOR ISOLATED TO WIDELY SCATTERED CONVECTIVE ACTIVITY TO
FORM WEDNESDAY AFTERNOON. THIS ACTIVITY WILL BE DIURNALLY INDUCED
AS TEMPERATURES WARM INTO THE MID TO UPPER 80S AND MLCAPE EXCEEDS
1000 J/KG. OVERALL, A RETURN TO THE WARMER AND MORE HUMID PATTERN
SEEN RECENTLY IS EXPECTED TO RETURN BY THE MIDDLE OF NEXT WEEK.
AVIATION
(00Z TAFS)
ISSUED AT 630 PM CDT THU APR 30 2026
QUITE A SPREAD IN CONDITIONS ACROSS THE FORECAST TERMINALS AT
ISSUANCE TIME, FROM VFR TO IFR. CURRENT CLUSTER OF SHRA/TSRA
MOVING ACROSS THE TERMINALS WITH AT LEAST BRIEF IFR CONDITIONS
THROUGH ABOUT 03-04Z. LIKELY TO BE ABOUT A 6 HOUR BREAK IN
PRECIPITATION, BUT STILL LIKELY TO HAVE MVFR TO IFR CONDITIONS
AFTER THE PRECIPITATION DEPARTS. PROB30 SHOULD BE GOOD ENOUGH TO
COVER THE PRECIPITATION THREAT DURING THE MORNING HOURS FRIDAY AT
MOST TERMINALS, BUT WILL NEED TO AT LEAST CONSIDER TEMPO OR
PREVAILING CONDITIONS FOR SHOWERS AND STORMS TOMORROW AFTERNOON,
AND CONTINUING INTO TOMORROW NIGHT. MAY NOT SEE VFR CONDITIONS
RETURN UNTIL PERHAPS MIDDAY SATURDAY.
MARINE
ISSUED AT 1225 PM CDT THU APR 30 2026
WINDS WILL BE VARIABLE IN DIRECTION THIS AFTERNOON INTO TONIGHT AS A
STATIONARY FRONT REMAINS PARKED OVER THE AREA. TO THE NORTH OF THE
FRONT IN THE TIDAL LAKES AND SOUNDS, NORTHEAST WINDS OF 10 TO 15
KNOTS WILL PERSIST INTO THE OVERNIGHT HOURS. SOUTH OF THE FRONT,
SOUTHEAST WINDS OF 5 TO 10 KNOTS WILL BE THE RULE THROUGH TONIGHT.
TOMORROW, A DEVELOPING LOW PRESSURE SYSTEM WILL MOVE INTO THE AREA
ALONG THE FRONT. WINDS WILL INCREASE IN RESPONSE TO THIS LOW WITH
NORTHEAST WINDS OF 15 TO 20 KNOTS FORMING OVER THE TIDAL LAKES AND
SOUNDS AND SOUTHEAST WINDS OF 10 TO 15 KNOTS DEVELOPING IN THE OPEN
GULF WATERS. AS THE LOW TRACKS TO THE EAST, IT WILL HELP DRIVE THE
FRONT OFFSHORE FRIDAY NIGHT INTO SATURDAY. STRONG NORTHERLY WINDS
OF 20 TO 25 KNOTS WILL DEVELOP FRIDAY NIGHT AND PERSIST THROUGH
SUNDAY MORNING OVER ALL OF THE WATERS, AND A SMALL CRAFT ADVISORY
WILL BE ISSUED FOR THESE CONDITIONS BY TOMORROW. WINDS AND SEAS
WILL QUICKLY FALL OFF TO LESS THAN 10 KNOTS AND 3 FEET SUNDAY NIGHT
INTO MONDAY AS A BROAD AREA OF HIGH PRESSURE SETTLES OVER THE
REGION. AS THE HIGH SHIFTS TO THE EAST ON TUESDAY, WINDS WILL TURN
SOUTHERLY AT AROUND 10 KNOTS.
LIX WATCHES/WARNINGS/ADVISORIES
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
SHORT TERM...PG
LONG TERM....PG
AVIATION...RW
MARINE...PG
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