893
FXUS64 KLIX 121835
AFDLIX
AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
135 PM CDT SAT SEP 12 2026
..NEW SHORT TERM, LONG TERM, AVIATION, MARINE
KEY MESSAGES
UPDATED AT 134 PM CDT SAT SEP 12 2026
- AN ELEVATED RISK FOR LOCALIZED HEAVY RAINFALL LEADING TO STREET
FLOODING AND OVERFLOWING OF POOR DRAINAGE WILL CONTINUE THIS
AFTERNOON AND AGAIN ON SATURDAY.
- LOWER RAIN CHANCES AND WARMER TEMPS RETURN FIRST HALF OF NEXT
WEEK.
SHORT TERM
(NOW THROUGH SUNDAY)
ISSUED AT 134 PM CDT SAT SEP 12 2026
A WEAK MID-LEVEL SHORTWAVE WILL CONTINUE TO MOVE SLOWLY THROUGH THE
LOWER MISSISSIPPI VALLEY TODAY. THE ENVIRONMENT ACROSS THE FORECAST
AREA VARIES FROM LESS TO MORE CONVECTIVELY FAVORABLY. WV IMAGERY
CURRENTLY SHOWS QUITE DRY MID LEVEL AIR MOVING IN FROM THE
NORTHWEST. TPW SATELLITE BLENDED PW REFLECTS THIS AS WELL, THOUGH
ITS NOT AS EVIDENT DUE TO HIGH LOW LEVEL MOISTURE IN PLACE.
REGARDLESS, PW VALUES GENERALLY RANGING FROM AROUND 1.7 INCHES
INLAND TO OVER 2 INCHES CLOSER TO THE COASTAL AREAS OF LA AND MS.
CURRENT SHOWER/STORM ACTIVITY THUS IS PRETTY MUCH WHERE YOU'D EXPECT
IT TO BE OR NOT BE...LESS OVER NORTHERN HALF OF THE CWA AND MORE TO
THE SOUTH. HEAVY RAIN WILL REMAIN THE PRIMARY CONCERN WITH ANY MORE
PERSISTENT CONVECTION. DEEPER MOISTURE AND RELATIVELY WEAK STEERING
FLOW WILL SUPPORT EFFICIENT RAINFALL PROCESSES, AND LOCALIZED RATES
OF 1 TO 3 INCHES PER HOUR WILL BE POSSIBLE IN THE STRONGEST CELLS.
MOST LOCATIONS WILL NOT SEE AMOUNTS ANYWHERE NEAR THAT HIGH, BUT
REPEATED DEVELOPMENT ALONG REMNANT OUTFLOW BOUNDARIES OR OTHER
MESOSCALE CONVERGENCE ZONES COULD QUICKLY PRODUCE SEVERAL INCHES IN
A SMALL AREA. CONVECTION SHOULD GRADUALLY DIMINISH THIS EVENING WITH
THE LOSS OF DAYTIME HEATING.
THAT SHORTWAVE BEGINS PULLING FARTHER EAST SUNDAY WHICH WILL CAUSE
HEIGHTS TO RISE FROM THE WEST AND THE SOUTHERN PLAINS UPPER RIDGE
BEGINS EXPANDING TOWARD THE REGION. THIS SHOULD MARK THE START OF A
TRANSITION TOWARD A MORE TYPICAL LATE-SUMMER CONVECTIVE PATTERN,
WITH STORMS INCREASINGLY TIED TO THE SEA BREEZE, DIFFERENTIAL
HEATING, AND LEFTOVER OUTFLOW BOUNDARIES. RAIN CHANCES WILL DECREASE
FROM SATURDAY BUT WILL NOT DISAPPEAR WITH THE AREA STILL ON THE
EASTERN PERIPHERY OF THE RIDGE. INCREASING SUNSHINE SHOULD ALSO
ALLOW TEMPERATURES TO BEGIN TRENDING UPWARD WITH HIGHS IN THE LOWER
TO POSSIBLY MID 90S.
MEFFER
LONG TERM
(MONDAY THROUGH FRIDAY NIGHT)
ISSUED AT 134 PM CDT SAT SEP 12 2026
THE UPPER RIDGE BECOMES ESTABLISHED ACROSS THE TENNESSEE
VALLEY/NORTHERN ALABAMA REGION MONDAY AND SHOULD REMAIN THE DOMINANT
FEATURE THROUGH AT LEAST THE MIDDLE OF THE WEEK. INCREASING
SUBSIDENCE BENEATH THE RIDGE WILL RESULT IN A NOTICEABLE REDUCTION
IN CONVECTIVE COVERAGE COMPARED WITH THE WEEKEND, ALTHOUGH ENOUGH
BOUNDARY-LAYER MOISTURE SHOULD REMAIN FOR ISOLATED TO SCATTERED
AFTERNOON STORMS ALONG THE SEA BREEZE AND OTHER MESOSCALE
BOUNDARIES. MONDAY SHOULD BEGIN THE WARMER PORTION OF THE FORECAST
WITH HIGHS GENERALLY IN THE LOWER TO MIDDLE 90S.
TUESDAY AND WEDNESDAY CURRENTLY APPEAR TO BE THE HOTTEST AND
RELATIVELY DRIEST DAYS AS THE 596-598DM RIDGE REMAINS STRONGEST
OVERHEAD OR JUST TO THE NORTH. AFTERNOON HIGHS IN THE LOWER TO
MIDDLE 90S COMBINED WITH DEWPOINTS GENERALLY IN THE LOWER TO MIDDLE
70S SHOULD YIELD HEAT INDICES LARGELY IN THE 100 TO 107 DEGREE
RANGE. THATS MOSTLY BELOW THE 108 DEGREE HEAT ADVISORY CRITERIA, BUT
THERE'S NOT MUCH ROOM TO SPARE. A FEW LOCALIZED LOCATIONS COULD
REACH JUST ABOVE 108, PARTICULARLY TUESDAY, IF TEMPERATURES REACH
THE WARMER END OF GUIDANCE WHILE DEWPOINTS REMAIN ELEVATED.
CONVERSELY, GREATER MIXING OR AN ISOLATED AFTERNOON STORM WOULD
KNOCK APPARENT TEMPERATURES DOWN QUICKLY. WARM OVERNIGHT LOWS IN THE
MIDDLE 70S INLAND AND UPPER 70S AROUND THE URBAN/COASTAL CORRIDOR
WILL ALSO PROVIDE ONLY MODEST OVERNIGHT RELIEF. STRONG SUBSIDENCE
FROM THAT RIDGE WILL REALLY STUNT POPS AS WELL DURING THIS
TIMEFRAME.
PATTERN CHANGE LOOKS TO THEN BE COMING THURSDAY. GLOBAL MODELS
CONTINUE TO FAVOR SOME WEAKENING OF THE PORTION OF THE UPPER RIDGE
ALOFT AS AN INVERTED TROUGH OR AN UPPER LOW APPROACHES FROM THE
FLORIDA/WESTERN ATLANTIC REGION. THIS WOULD ALLOW DEEPER MOISTURE TO
BEGIN RETURNING, WITH AN INCREASE IN AFTERNOON SHOWER AND
THUNDERSTORM COVERAGE AND A CORRESPONDING EASING OF DAYTIME
TEMPERATURES. ONE INTERESTING FEATURE TO WATCH WITH THIS SYNOPTIC
EVOLUTION IS DRY SLOT ON THE NORTHWESTERN SIDE OF THE UPPER LOW
COMING ACROSS THE GULF. MODELS SUGGEST IT MAY BE PULLING IN DRY AIR
CAUGHT UNDERNEATH THE RIDGE INTO THE CWA, EFFECTIVELY KEEPING RAIN
CHANCES DOWN QUITE A BIT INLAND WITH MOST OF THE CONVECTION ALONG
THE COAST AND IN THE OPEN GULF WATERS.
MEFFER
AVIATION
(18Z TAFS)
ISSUED AT 134 PM CDT SAT SEP 12 2026
VFR CONDITIONS WILL DOMINATE THE FORECAST PERIOD OUTSIDE OF
CONVECTION. RADAR SHOWS WIDESPREAD LIGHT TO MODERATE SHOWERS WITH
ISOLATED STORMS MIXED IN MAINLY FROM KMSY/KNEW AND SOUTHWARD.
CONVECTION IS MUCH MORE SPARSE NORTH OF THERE DUE TO DRY AIR IN THE
MID LEVELS AND TRIED TO ADJUST PROB30 GROUPS TO REFLECT THAT. SHOULD
START TO SEE THIS ACTIVITY DWINDLE AS DAYTIME HEATING WANES LATE
THIS AFTERNOON INTO THE EARLY EVENING HOURS. ANY DIRECT THUNDERSTORM
IMPACT COULD PRODUCE BRIEF IFR VISIBILITY IN HEAVY RAIN, LOWER
CEILINGS, FREQUENT LIGHTNING, AND GUSTY OUTFLOW WINDS. FOG POTENTIAL
IS LOW OUTSIDE OF POSSIBLY -BR AT KMCB NEAR SUNRISE SUNDAY.
CONVECTIVE COVERAGE SHOULD BE LOWER TOMORROW AS UPPER LEVEL RIDGING
AND ASSOCIATED SUBSIDENCE BEGINS MOVING IN FROM THE WEST SUNDAY.
MEFFER
MARINE
ISSUED AT 134 PM CDT SAT SEP 12 2026
WINDS ARE GRADUALLY TURNING MORE SOUTH-SOUTHWESTERLY WITH THE
BERMUDA RIDGE CENTERED EAST OF THE AREA AND BUILDING WEST ACROSS THE
GULF. WIND SPEEDS SHOULD BE LIGHT AT 10 KNOTS OR LESS AS THE
PRESSURE GRADIENT IS QUITE WEAK. A SMALLER SCALE RIDGE OF HIGH
PRESSURE WILL DEVELOP MORE CENTERED OVER THE NORTH-CENTRAL GULF NEXT
WEEK. THIS WILL CAUSE WINDS TO BECOME EVEN LIGHTER AND VARIABLE AT
TIMES. WITH THOSE LIGHT WINDS, WAVES/SEAS WILL GENERALLY REMAIN IN
THE 2 FEET OR LESS RANGE. ADDITIONALLY, THUNDERSTORM ACTIVITY WILL
DEVELOP EACH DAY, PEAKING IN THE EARLY TO MID-MORNING HOURS, AND
THESE STORMS WILL PRODUCE HIGHER WIND GUSTS, WATERSPOUTS, AND
LIGHTNING CONCERNS.
MEFFER
LIX WATCHES/WARNINGS/ADVISORIES
LA...NONE.
GM...NONE.
MS...NONE.
GM...NONE.
SHORT TERM...ME
LONG TERM....ME
AVIATION...ME
MARINE...ME
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page