Area Forecast Discussion
Issued by NWS New Orleans/Baton Rouge, LA

Home | Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33

506
FXUS64 KLIX 200111
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
811 PM CDT TUE AUG 19 2014

...SOUNDING DISCUSSION...

THIS EVENING/S BALLOON ONCE AGAIN SAMPLED A FAIRLY MOIST AND
UNSTABLE ATMOSPHERE WHICH IS NOT UNUSUAL FOR THIS TIME OF YEAR. A
LITTLE MORE MOISTURE HAS MOVED INTO THE MIDLEVELS...ESPECIALLY
NOTED BETWEEN 525 AND 400MB. PRECIPITABLE WATER VALUES ARE JUST A
BIT ABOVE NORMAL FOR THIS TIME OF YEAR WITH TONIGHT/S PW MEASURED
AT 1.97 INCHES. WINDS WERE PRIMIARILY FROM A WESTERLY DIRECTION UNDER
20 KNOTS FROM THE SURFACE UP TO 300MB. THEN THE WINDS WERE LIGHT
AND VARIABLE ABOVE THAT LEVEL TO 100MB. OVERALL...THE TEMPERATURE
HAS CHANGED LITTLE AT ANY GIVEN LEVEL COMPARED TO 24 HOURS AGO.

00Z BALLOON INFO: A ROUNTINE FLIGHT THIS EVENING WITH NO ISSUES.
THE BALLOON TRAVELED 25 MILES DOWNRANGE BEFORE BURSTING OVER THE
NORTHWEST PART OF LAKE PONTCHARTRAIN AT A HEIGHT OF 21.7 MILES
ABOVE THE GROUND.

ANSORGE

&&

.PREV DISCUSSION... /ISSUED 327 PM CDT TUE AUG 19 2014/

SHORT TERM...

AN UPPER LEVEL RIDGE WILL CONTINUE TO STRENGTHEN OVER THE GULF
SOUTH OVER THE NEXT 72 HOURS. WITH THIS STRENGTHENING RIDGE IN
PLACE...INCREASED SUBSIDENCE AND CAPPING ALOFT WILL HELP LIMIT
OVERALL CONVECTIVE POTENTIAL. HAVE KEPT IN A TOKEN 20 PERCENT POP
FOR THE AREA...WITH THE POP HIGHEST IN THE AFTERNOON HOURS WHEN
OVERALL INSTABILITY WILL BE MAXIMIZED. HOWEVER...IT WILL BE
DIFFICULT TO GET MUCH CONVECTIVE ACTIVITY AS THE CONVECTIVE
TEMPERATURE PUSHES INTO THE UPPER 90S. IF CONVECTION DOES FORM
WILL TEND TO DEVELOP IN AREAS OF ENHANCED LOW LEVEL CONVERGENCE
WHERE WEAK LOW LEVEL FORCING COULD ASSIST IN OVERCOMING THE CAP
ALOFT. THIS CONVERGENCE WILL GENERALLY BE FOUND ALONG ANY
LAKEBREEZE AND SEABREEZE FRONTAL BOUNDARIES AND OUTFLOW BOUNDARIES
THAT DEVELOP THROUGH THE DAY. TEMPERATURES WILL RISE INTO THE
MIDDLE TO UPPER 90S ACROSS THE FORECAST AREA...WITH HEAT INDEX
READINGS PUSHING TO AROUND 105 DEGREES EACH AFTERNOON. OVERNIGHT
LOWS ARE PROJECTED TO COOL ENOUGH TO ALLOW FOR RECOVERY FROM THE
HEAT...SO HEAT ADVISORIES ARE LOOKING LESS LIKELY NOW.
HOWEVER...THIS WILL BE THE WARMEST AIRMASS OF THE SEASON THROUGH
THE END OF THE WEEK.

LONG TERM...

HEADING INTO THE FIRST HALF OF NEXT WEEK...THERE IS A LARGE
DIFFERENCE IN MODEL SOLUTIONS. GIVEN THE CONSISTENCY OF THE ECMWF
RUNS...HAVE WENT THIS SOLUTION FOR THE EXTENDED FORECAST. WITH
THIS IN MIND...EXPECT TO SEE THE STRONG 595 RIDGE SHIFT TO THE
NORTH AND WEST...PLACING THE GULF SOUTH IN A MORE EAST AND
NORTHEAST FLOW PATTERN. A WEAK VORT MAX ROUNDING THE PERIPHERY OF
THE RIDGE WILL SLIDE INTO THE AREA FROM THE NORTHEAST ON MONDAY
AND LINGER INTO TUESDAY. HAVE KEPT CHANCE POPS IN FOR MONDAY AND
TUESDAY TO REFLECT THIS RISK. HOWEVER...ON SUNDAY THE POPS WERE
LOWERED TO SLIGHT CHANCE AS THE RIDGE AXIS SHOULD STILL BE FIRMLY
IN CONTROL OF THE REGION AT THAT TIME. TEMPERATURES WILL REMAIN
WARM...BUT SHOULD MODERATE BACK TO MORE NORMAL READINGS FOR LATE
AUGUST.

AVIATION...

VFR CONDITIONS WILL PREVAIL THROUGH THE PERIOD. ONLY EXCEPTION
MIGHT BE IN VICINITY OF VERY ISOLATED CONVECTION. PROBABILITY OF
PRECIP AT ANY GIVEN TAF SITE REMAINS TOO LOW TO INCLUDE IN TAFS AT
THIS TIME...SO WILL NEED TO MONITOR RADAR TRENDS FOR ANY NECESSARY
SHORT TERM AMENDMENTS CONCERNING CONVECTIVE IMPACTS. 95/DM

MARINE...

WINDS WILL GENERALLY BE FROM THE SOUTH AND SOUTHWEST AT AROUND 10
KNOTS THROUGH THURSDAY. AS A SURFACE HIGH BECOMES CENTERED OVER
THE AREA THIS WEEKEND...WINDS WILL TURN MORE VARIABLE. A NOCTURNAL
LOW LEVEL JET WILL DEVELOP OFF THE MISSISSIPPI COAST EACH NIGHT AS
A MESOHIGH OVER LAND INTERACTS WITH LOWER PRESSURES FURTHER
OFFSHORE. THIS WILL BRING INCREASED WESTERLY WINDS OF 10 TO 15
KNOTS TO THE SOUNDS AND NEARSHORE WATERS EAST OF THE RIVER EACH
NIGHT. WINDS WILL THEN WEAKEN AND SHIFT TO A MORE SOUTHERLY
COMPONENT DURING THE LATE MORNING AND AFTERNOON HOURS. SEAS WILL
GENERALLY RANGE FROM 1 TO 3 FEET...WITH THE HIGHEST SEAS EXPECTED
WHERE THE NOCTURNAL LOW LEVEL JET DEVELOPS.

DECISION SUPPORT...

DSS CODE...GREEN.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.

DECISION SUPPORT SERVICES (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 SEVERE; NEARBY
         TROPICAL EVENTS; HAZMAT OR OTHER LARGE EPISODES
RED    = FULL ENGAGEMENT FOR MODERATE TO HIGH RISK SVR
         AND/OR DIRECT TROPICAL THREATS; EVENTS OF NATIONAL
         SIGNIFICANCE.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  74  95  74  94 /  10  20  10  20
BTR  76  95  76  95 /  10  20  10  20
ASD  77  93  76  93 /  10  20  10  20
MSY  78  93  77  92 /  10  20  10  20
GPT  78  93  78  93 /  10  20  10  20
PQL  77  92  76  94 /  10  20  10  10

&&

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

$$







USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.