643  
FXUS64 KLIX 212240  
AFDLIX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NEW ORLEANS LA  
440 PM CST SAT DEC 21 2024  
   
..NEW SHORT TERM, LONG TERM, AVIATION, MARINE
 
 
   
SHORT TERM
 
 
(THIS EVENING THROUGH MONDAY NIGHT)  
ISSUED AT 438 PM CST SAT DEC 21 2024  
 
QUITE THE NICE DAY TODAY IF YOU LIKE COOL TEMPS. LUCKILY IT WAS  
FULL SUN WHICH KEPT IT FROM FEELING TOO CHILLY. THIS IS SETTING UP  
THE AREA FOR A CHILLY NIGHT WITH MULTIPLE LOCATIONS ACROSS THE  
NORTHERN HALF OF THE AREA DROPPING TO NEAR OR BELOW FREEZING.  
 
THE NEXT 48 TO 60 HOURS WILL GENERALLY BE QUIET WITH ONLY A FEW  
IMPACTS EXPECTED. FIRST WILL BE MODERATE TO LIGHT FREEZING  
CONDITIONS FOR THE NORTHERN HALF/3RD OF THE CWA AND THE 2ND ISSUE  
COULD BE SOME FOG TUESDAY MORNING.  
 
TONIGHT WILL BE COLD. HIGH PRESSURE AT THE SFC WILL MAINTAIN CONTROL  
OVER THE AREA LEADING TO WINDS QUICKLY DECOUPLING WITH TEMPS QUICKLY  
FALLING THIS EVENING. CLEAR SKIES AND LIGHT WINDS THROUGH THE BL  
SHOULD PROVIDE A VERY FAVORABLE RADIATIONAL COOLING SET UP. IN  
ADDITION WITH AFTERNOON DEWPOINTS FALLING INTO THE MID 20S TO LOWER  
30S LOWS TONIGHT SHOULD GET PRETTY CLOSE TO THOSE OVER MUCH OF THE  
AREA. NBM IS ON THE HIGHER END OF THE SPREAD SO WE WILL TREND CLOSER  
TO THE MOS AND NBM50. THIS SHOULD LEAD TO MID TO UPPER 20S ACROSS  
SOUTHWEST MS AND THE PEARL RIVER AND PASCAGOULA DRAINAGE AREAS. JUST  
OUTSIDE OF THOSE AREAS AND ACROSS THE I-12 CORRIDOR ALONG WITH  
COASTAL MS LOWS SHOULD FALL IN THE LOWER TO MID 30S. WHILE THE RIVER  
PARISHES AND WEST BANK SHOULD SEE MID TO UPPER 30S AND THE  
SOUTHSHORE CLOSER TO 40.  
 
MONDAY THROUGH TUESDAY WE WILL BEGIN TO MODERATE. HIGH PRESSURE  
SLIDES OFF TO THE NORTHEAST WITH RETURN FLOW SLOWLY SETTING BACK BUT  
IT WILL TAKE TIME TO SEE MOISTURE RECOVER. AS FOR THE FOG POTENTIAL  
TUESDAY MORNING IT IS NOT QUITE LOOKING AS FAVORABLE AS PREVIOUSLY  
THOUGHT. AS MENTIONED THE RETURN FLOW WILL SLOWLY BE SETTING BACK UP  
WITH MOISTURE LIKELY NOT REALLY RECOVERING UNTIL TUESDAY MORNING  
AND THROUGH THE DAY. WINDS JUST ABOVE THE BOUNDARY LAYER MAY BE A  
LITTLE STRONGER AND THAT COULD LEAD TO MORE OF A STRATUS DECK. BY  
AFTERNOON WE MAY BEGIN TO SEE A FEW SPRINKLES OR LIGHT SHOWERS AS  
WEAK ISENTROPIC LIFT INCREASES ACROSS COASTAL AREAS AND INTO THE  
AREA BUT OVERALL PROBABLY LOOKING AT MOSTLY CLOUDY TO OVERCAST  
SKIES. CHRISTMAS EVE AND THROUGH THE REST OF THE WEEK THE FORECAST  
BECOMES FOR MORE UNCERTAIN AND ACTIVE. /CAB/  
 

 
   
LONG TERM
 
 
(TUESDAY THROUGH FRIDAY NIGHT)  
ISSUED AT 438 PM CST SAT DEC 21 2024  
 
MEDIUM RANGE MODELS QUICKLY STRUGGLE WITH THE PATTERN EVEN AS  
EARLY AS CHRISTMAS DAY. ONE THING FOR SURE IS IT WILL BE ACTIVE  
WITH MULTIPLE ROUNDS OF RAIN AND EVEN THE SMALL POSSIBILITY OF  
STRONG TO SEVERE STORMS ALONG WITH LOCALLY HEAVY RAIN. GIVEN THE  
UNCERTAINTY IN THE FORECAST WITH TIMING, STRENGTH, AND AMOUNTS WE  
WILL STICK RATHER CLOSELY TO THE NBM.  
 
FIRST SYSTEM LOOKS TO BE OVERNIGHT CHRISTMAS EVE THROUGH CHRISTMAS  
DAY. A RATHER IMPRESSIVE IMPULSE WILL DROP DOWN THE LEE SIDE OF THE  
ROCKIES WITH A S/W DIGGING AS IT MOVES EAST ACROSS THE PLAINS. THE  
PROBLEM IS THE MODES ARE ALREADY DIVERGING WITH A STRONGER FASTER  
IMPULSE IN THE GFS AND A WEAKER SLOW ONE IN THE ECMWF. THE ECMWF  
ALSO HAS A SLIGHTLY STRONGER RIDGE AHEAD OF THE S/W. IT ALSO A RIDGE  
ABV THE TROUGH WHERE THE GFS IS MORE OF A [PHASED TROUGH FROM CENTRAL  
CANADA AND A AMPLIFIED RIDGE OVER THE ROCKIES. WITH THAT THE GFS  
QUICKLY BRINGS SHOWERS AND MAYBE A FEW THUNDERSTORMS INTO THE CWA  
OVERNIGHT MAYBE EVEN BEFORE 6Z. THE ECMWF DOESN'T REALLY BRING THE  
BULK OF THE RAIN INTO THE AREA UNTIL MORNING AND MIDDAY HOURS. RIGHT  
NOW EITHER SOLUTION MAINLY JUST BRINGS RAIN, EVEN WITH A STRONG S/W  
SOLUTION WE DON'T RECOVER ENOUGH TO REALLY INCREASE THE INSTABILITY.  
WITH THAT IT LOOKS LIKE AT THE LEAST THE FIRST HALF OF CHRISTMAS  
COULD BE A LITTLE WET.  
 
NOW THE ISSUE WITH THIS SYSTEM IS THAT IT IS QUICKLY WEAKENING AS IT  
MOVES ACROSS THE AREA AND LIFTING. THIS DROPS A VERY WEAK FRONT INTO  
THE REGION BUT IT DOESN'T MOVE THROUGH OUR AREA AND QUICKLY RETREATS  
NORTH OF COMPLETELY LOSES ITS IDENTITY. THIS MEANS WE DO NOT GET  
CLEANED OUT BY ANY FRONTAL PASSAGE OR DISTURBANCE AND LEAVES AN  
UNSETTLED AND MOIST ENVIRONMENT IN PLACE. AT THIS TIME FROM THURSDAY  
AND INTO THE NEXT WEEKEND MULTIPLE DISTURBANCES WORK ACROSS THE  
ROCKIES AND INTO THE PLAINS AND THEN LIFT NORTHEAST ACROSS THE MID  
AND UPPER MS VALLEY. THE PROBLEM IS THE MODELS ARE ALL OVER WITH  
TIMING AND STRENGTH OF THESE INDIVIDUAL DISTURBANCES AND EACH COULD  
BRING ANOTHER SHOT OF CONVECTION INTO THE AREA BUT STRENGTH/SEVERITY  
WILL BE VERY DEPENDENT ON THE TRACK OF EACH DISTURBANCE. ONE THING  
TO MENTION IS THAT MODELS HAVE BEEN AGGRESSIVE SHOWING A POTENT  
SYSTEM AROUND THE 26TH/27TH TIME FRAME FOR SOME TIME. A FEW TIMES  
THEY HAVE LOST IT BUT THEN COME BACK A RUN OR TWO LATER. WITH SO  
MUCH ENERGY COMING OUT OF THE PACIFIC AND THE MODELS WILL STRUGGLE  
SOMEWHAT BUT CONFIDENCE IS INCREASING IN THE THREAT OF SOME  
SIGNIFICANT IMPACTS ACROSS THE MS VALLEY AROUND WEEKS END. MAYBE AS  
FAR SOUTH AS OUR AREA BUT EVEN IF NOT HERE IF YOU ARE TRAVELING  
BETWEEN THE 25 AND 28TH PLEASE PAY ATTENTION TO THE FORECAST BETWEEN  
HERE AND YOUR DESTINATION AS THERE IS A GOOD CHANCE THAT YOU COULD  
SEE THOSE IMPACTS FROM POSSIBLE SEVERE WEATHER. /CAB/  
 

 
   
AVIATION
 
 
(00Z TAFS)  
ISSUED AT 438 PM CST SAT DEC 21 2024  
 
NO ISSUES FOR ANY OF THE TERMINALS. VFR CONDITIONS WILL  
CONTINUE WITH NO FOG OR LOW CLOUDS IN SIGHT. /CAB/  
 

 
   
MARINE
 
 
ISSUED AT 438 PM CST SAT DEC 21 2024  
 
MARINE CONDITIONS WILL REMAIN BENIGN FOR NOW WITH HIGH PRESSURE  
STILL IN CONTROL. THE SFC HIGH STARTS TO MOVE TO THE NORTHEAST  
LATE TOMORROW AND THIS WILL SLOWLY LEAD TO ONSHORE FLOW RETURNING  
MONDAY THROUGH TUESDAY. LIGHT SHOWERS MAY ALSO START TO RETURN  
OVER THE OPEN WATERS ACROSS THE GULF. /CAB/  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
MCB 27 55 31 63 / 0 0 0 0  
BTR 34 60 36 68 / 0 0 0 0  
ASD 30 58 33 66 / 0 0 0 0  
MSY 40 57 44 66 / 0 0 0 0  
GPT 33 57 36 63 / 0 0 0 0  
PQL 29 60 32 67 / 0 0 0 0  
 

 
   
LIX WATCHES/WARNINGS/ADVISORIES
 
 
LA...NONE.  
GM...NONE.  
MS...NONE.  
GM...NONE.  

 
 

 
 
SHORT TERM...CAB  
LONG TERM....CAB  
AVIATION...CAB  
MARINE...CAB  
 
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