255  
FXUS64 KLIX 190839  
AFDLIX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NEW ORLEANS LA  
339 AM CDT THU OCT 19 2017  
   
SYNOPSIS
 
 
AT THE SURFACE, HIGH PRESSURE OFF THE VIRGINIA COAST EXTENDS  
SOUTHWESTWARD INTO EAST TEXAS. AN UPPER RIDGE IS CURRENTLY  
CENTERED OVER THE GREAT PLAINS STATES. ONLY SOME HIGH CLOUDINESS  
MOVING ACROSS THE AREA. TEMPERATURES SHOWING QUITE A WIDE RANGE  
ACROSS THE AREA DEPENDING ON PROXIMITY TO VERY WARM WATER.  
TEMPERATURES RANGING FROM 51 AT BOGALUSA TO 76 AT BOOTHVILLE.  
 

 
   
SHORT TERM
 
 
HIGH PRESSURE AT THE SURFACE AND ALOFT WILL CONTINUE TO MOVE  
EASTWARD OVER THE NEXT COUPLE OF DAYS. THIS WILL ALLOW MOISTURE  
LEVELS TO FINALLY INCREASE AS EASTERLY WINDS GAIN A SOUTHERLY  
COMPONENT. COULD START TO SEE AT LEAST SCATTERED SHOWERS SOUTH OF  
LAKE PONTCHARTRAIN AS EARLY AS FRIDAY NIGHT, WITH SHOWERS/STORMS  
BECOMING LIKELY ACROSS MUCH OF THE AREA BY SATURDAY AFTERNOON.  
 
HIGH TEMPERATURES WILL BE IN THE LOWER TO MIDDLE 80S THROUGH  
SATURDAY, WHICH IS ABOUT 5-8 DEGREES ABOVE NORMAL. OVERNIGHT LOWS  
WILL GRADUALLY MODERATE, WITH ALL AREAS IN THE 60S TO LOWER 70S BY  
SATURDAY MORNING. THIS IS A GOOD 10-15 DEGREES ABOVE NORMAL FOR  
MID OCTOBER. 35  
   
LONG TERM
 
 
UNFORTUNATELY, WHILE THE SHORT TERM PART OF THE FORECAST WAS  
FAIRLY STRAIGHTFORWARD, THE LONG TERM PORTION IS NOT. ECMWF AND  
GFS OPERATIONAL RUNS HAVING DIFFICULTY RESOLVING THEIR DIFFERENCES  
AT 500 MB, WITH THE GFS A GOOD 12-24 HOURS FASTER AT 500 MB BY  
MONDAY MORNING. SIMILAR DIFFERENCES EXIST AT THE SURFACE SUNDAY  
AFTERNOON. PREVIOUS FORECAST PACKAGE WAS BASED CLOSE TO THE GFS.  
THAT SOLUTION HAD A LOCAL FRONTAL PASSAGE LATE SUNDAY OR SUNDAY  
NIGHT, AND DON'T SEE ANY MAJOR REASONS TO MAKE A SWITCH. ONLY  
QUESTION HERE IS WHICH MODEL BUSTS ON MONDAY, AS GFS IS PRETTY  
MUCH DRY WITH THE ECMWF CARRYING LIKELY POPS FOR SOME PORTIONS OF  
THE AREA. IN COORDINATION WITH SURROUNDING OFFICES, WILL CARRY  
PRECIPITATION IN THE MONDAY FORECAST GIVING AT LEAST SOME CREDENCE  
TO THE SLOWER SOLUTION.  
 
ONCE THE FRONTAL SYSTEM CLEARS THE AREA, COOLER WEATHER RETURNS  
WITH TEMPERATURES NEAR TO BELOW NORMAL AFTER MONDAY. WILL GO WITH  
A MIDDLE OF THE ROAD SOLUTION ON TEMPS, AS IT APPEARS THAT THE MEX  
NUMBERS MIGHT BE A LITTLE TOO COOL. 35  
 

 
   
AVIATION
 
 
VFR CATEGORY CONDITIONS ARE EXPECTED AT EACH OF THE TERMINALS  
THROUGHOUT THE TAF FORECAST PERIOD. 11  
 

 
   
MARINE
 
 
MODERATE TO OCCASIONALLY STRONG EASTERLY FLOW WILL CONTINUE ACROSS  
THE COASTAL WATERS THROUGH THE END OF THE WEEK. THIS WILL RESULT IN  
EXERCISE CAUTION CONDITIONS THAT MAY FLIRT WITH SMALL CRAFT ADVISORY  
CRITERIA AT TIMES, AT LEAST OVER THE OPEN GULF WATERS. THE WINDS  
WILL EASE AND SHIFT TO THE SOUTHEAST SUNDAY IN ADVANCE OF A COLD  
FRONT THAT WILL MOVE THROUGH THE COASTAL WATERS SUNDAY NIGHT INTO  
MONDAY. MODERATE OFFSHORE FLOW WILL DEVELOP IN THE WAKE OF THIS  
FRONT FOR THE EARLY PART OF THE NEXT WORK WEEK. 11  
 

 
   
DECISION SUPPORT
 
 
DSS CODE: GREEN.  
DEPLOYED: NONE.  
ACTIVATION: NONE.  
ACTIVITIES: NONE.  
 
DECISION SUPPORT SERVICES (DSS) CODE LEGEND  
GREEN = NO WEATHER IMPACTS THAT REQUIRE ACTION.  
BLUE = LONG-FUSED WATCH, WARNING, OR ADVISORY IN EFFECT OR HIGH  
VISIBILITY EVENT.  
YELLOW = HEIGHTENED IMPACTS WITH SHORT-FUSED WATCH, WARNING OR  
ADVISORY ISSUANCES; RADAR SUPPORT.  
ORANGE = HIGH IMPACTS; SLIGHT TO MODERATE RISK SEVERE; NEARBY  
TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES.  
RED = FULL ENGAGEMENT FOR MODERATE RISK OF SEVERE AND/OR DIRECT  
TROPICAL THREATS; EVENTS OF NATIONAL SIGNIFICANCE.  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
MCB 80 57 83 64 / 0 0 0 10  
BTR 82 58 84 67 / 0 0 10 10  
ASD 82 59 84 66 / 0 0 10 10  
MSY 81 68 83 71 / 0 0 10 20  
GPT 81 62 83 68 / 0 0 10 10  
PQL 83 59 84 66 / 0 0 10 10  
 

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

 
 

 
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab LA Page
The Nexlab MS Page Main Text Page