234  
FXUS64 KLIX 222112  
AFDLIX  
 
AREA FORECAST DISCUSSION  
NATIONAL WEATHER SERVICE NEW ORLEANS LA  
412 PM CDT WED MAR 22 2017  
   
SYNOPSIS
 
 
LATEST SURFACE ANALYSIS SHOWED A WEAK COLD FRONT FROM NORTH  
FLORIDA TO MISSISSIPPI COAST TO WEST CENTRAL LOUISIANA. SURFACE  
DEWPOINT READINGS WERE IN THE MID TO UPPER 50S NORTH OF THE  
BOUNDARY AND 60 TO 65F SOUTH OF THE BOUNDARY. DRYING AND NORTH  
WINDS HAVE ALLOWED TEMPS TO CLIMB ESPECIALLY ALONG THE MISSISSIPPI.  
SURFACE FLOW WAS GENERALLY FROM THE NORTHWEST. UPPER AIR ANALYSIS  
SHOWED A GENERAL NORTHWEST FLOW FROM EAST COAST TO THE  
MISSISSIPPI VALLEY, RIDGE AXIS OVER THE PLAINS AND VIGOROUS WAVE  
APPROACHING THE WEST COAST. ISOTACH AT 250MB INITIALIZED JET MAX  
OF 120 KNOTS ON THE BACK SIDE OF THE WAVE OR OFF THE WEST COAST.  
 

 
   
SHORT TERM
 
 
FRONTAL ZONE ACROSS THE FORECAST AREA WILL BECOME STATIONARY  
THROUGH THURSDAY. AT THE SAME TIME, SURFACE TROUGH/LOW WILL DEEPEN  
AS THE UPPER LEVEL MOVES ACROSS THE ROCKIES THURSDAY INTO FRIDAY.  
THESE FEATURES WILL CREATE A GENERAL SOUTHEAST FLOW ACROSS THE  
FORECAST AREA BY MID DAY THURSDAY AND INCREASE THURSDAY NIGHT INTO  
FRIDAY.  
 
UPPER LEVEL WAVE/TROUGH WILL TRACK ACROSS THE ROCKIES AND  
EVOLVE INTO A CLOSED LOW LATE THURSDAY. MAX JET STREAK OF 100 TO  
110 KNOTS WILL MIGRATE TO THE BASE OF THE TROUGH. WHILE NO TRUE  
NEGATIVELY TILT OCCURS WITH THIS SYSTEM, ONE STRONG DISTURBANCE  
WILL ROTATE AROUND THE LOW AND ACROSS LOUISIANA AND MISSISSIPPI.  
SURFACE BASE CAPE WILL INCREASE ACROSS THE WEST ZONES FRIDAY  
AFTERNOON WITH VALUES 300 TO 600 J/KG. WILL INSERT SLIGHT CHANCE  
OF SHOWERS IN THE MORNING AND ADD SLIGHT CHANCE OF THUNDERSTORMS  
FRIDAY AFTERNOON.  
 
LOW LEVEL SOUTHEAST TO SOUTH FLOW AND SOUTHWEST FLOW ALOFT WILL  
INCREASE 0-3KM HELICITY VALUES 200 TO 350 M/S FRIDAY EVENING  
THROUGH EARLY SATURDAY MAINLY ACROSS THE NORTH HALF OF THE  
FORECAST AREA. CAPE VALUES DO INCREASE WITH VALUES OF 300 J/KG  
ACROSS SOUTHWEST MISSISSIPPI TO 1000 J/KG ALONG THE LOUISIANA.  
WITH THE DISTURBANCE ROTATING SOUTHEAST THROUGH THE FORECAST AREA  
FRIDAY NIGHT A FEW STORMS MAY CONTAIN DAMAGING WINDS AND/OR ONE OR  
TWO TORNADOES. AS FOR HAIL, 500MB TEMPS MAY DIP TO -17F ACROSS  
NORTHWEST ZONES BY SATURDAY. AS A RESULT, A FEW STORMS MAY CONTAIN  
HAIL, BUT COLD CORE LAGS BEHIND THE DISTURBANCE BUT FORCING MAY  
YIELD A FEW HAIL STORMS AHEAD OF THE COLD CORE.  
   
LONG TERM
 
 
WITH NO TRUE FRONTAL PASSAGE OVER THE WEEKEND, LOW LEVEL MOISTURE  
WILL REMAIN IN PLAY. HOWEVER, MID LAYER MOISTURE WILL BE PUSHED  
EAST PROVIDE A BREAK ON SUNDAY. A SHORT WAVE WILL RAKE ACROSS THE  
NORTH ZONES ON MONDAY YIELDING A FEW STORMS, BUT THESE STORMS  
SHOULD REMAIN BELOW SEVERE LIMITS. MEANWHILE IN THE LATTER PART OF  
THE FORECAST, A VERY STRONG SYSTEM WILL APPROACH THE LOWER  
MISSISSIPPI VALLEY LATE WEDNESDAY INTO THURSDAY. WHILE 7 TO 8 DAYS  
AWAY, THE PATTERN DOES SUPPORT A ROUND OF STRONG TO SEVERE ACROSS  
THE FORECAST AREA LATE NEXT WEEK. IT IS THAT TIME OF YEAR.  
 

 
   
AVIATION
 
 
VFR CONDITIONS ARE EXPECTED TO PREVAIL THROUGH MOST OF THE PERIOD.  
LOWER CIGS AND VSBYS WILL BE POSSIBLE NEAR DAYBREAK, RESULTING IN  
MVFR OR EVEN IFR CONDITIONS FOR A FEW HOURS.  
 

 
   
MARINE
 
 
WIND FIELD SHOULD REMAIN QUIET FOR ABOUT THE NEXT 24 HOURS. ONCE  
THE NEXT SYSTEM MOVES OUT OF THE ROCKIES SOMETIME THURSDAY, THE  
PRESSURE GRADIENT WILL TIGHTEN. WINDS ARE EXPECTED TO BECOME  
SOUTHEASTERLY BY LATE THURSDAY, AND WE WILL LIKELY NEED SMALL  
CRAFT EXERCISE CAUTION HEADLINES IN AT LEAST OUR FAR EASTERN  
WATERS AT THAT POINT. BY SUNRISE FRIDAY, MOST ALL WATERS SHOULD  
HAVE THE SCEC HEADLINE OR A SMALL CRAFT ADVISORY. THESE CONDITIONS  
LIKELY TO CONTINUE INTO SATURDAY BEFORE EASING.  
 

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

 
 
95/DM  
 

 
   
PRELIMINARY POINT TEMPS/POPS
 
 
MCB 57 83 63 77 / 0 10 10 20  
BTR 58 84 66 80 / 0 10 10 20  
ASD 60 79 65 78 / 0 10 10 20  
MSY 63 79 67 79 / 0 10 10 20  
GPT 61 76 65 73 / 0 10 10 20  
PQL 60 75 63 74 / 0 10 10 20  
 

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

 
 

 
 
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