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000
FXUS64 KLIX 212050
AFDLIX

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
350 PM CDT TUE MAY 21 2013

.SYNOPSIS...
LATEST SURFACE SHOWED A DEEP 1001MB LOW OVER SOUTHWEST MINNESOTA
WITH AN OCCLUDED FRONT EXTENDING EAST THEN A COLD FRONT SOUTHWEST
THROUGH MISSOURI TO OKLAHOMA TO CENTRAL TEXAS. RIDGE OF HIGH
PRESSURE REMAINED FROM THE MID ATLANTIC STATES TO NORTHEAST GULF.
SOUTHWEST FLOW BETWEEN THESE TWO FEATURES ALLOW GULF MOISTURE TO
FUNNEL FROM THE TEXAS COAST TO THE GREAT LAKES REGION. UPPER LEVEL
ANALYSIS SHOWED THE CYCLONIC CIRCULATION CENTERED OVER THE SURFACE
LOW BUT EXPANSIVE OVER THE UPPER MISSISSIPPI VALLEY AND NORTHERN
PLAINS. IN ADDITION...IR SATELLITE IMAGERY SHOWED A SMALLER
CYCLONIC CIRCULATION OVER TEXAS PANHANDLE. PRECIPITABLE WATER
VALUE PLANAR FIELD SHOWED THE DEEP MOISTURE POOLING ALONG THE
FRONT WITH VALUES 1.5 INCHES FROM NORTHEAST TEXAS TO CENTRAL
ARKANSAS...PW VALUES FROM 1.5 INCHES NW ZONES TO 1 INCH OVER MS
COAST. ISOTACH ANALYSIS AT 250MB SHOWED JET MAX OF 95 KNOTS ON THE
FRONT SIDE OF THE MAIN UPPER LOW/TROUGH...NORTHERN MISSOURI TO
WISCONSIN AND SUB-JET FROM SOUTH TEXAS TO WEST CUBA...PLACE A
DIVERGENCE FIELD OVER THE ARKLATEX REGION. IN OTHER WORDS...BEST
FIELDS FOR CONVECTION WILL OCCUR NORTHWEST OF THE FORECAST AREA
THIS AFTERNOON.

&&

.DISCUSSION...
MAIN UPPER LEVEL LOW/TROUGH WILL FILL OR OPEN TO A POSITIVELY TILTED
TROUGH. THIS WILL ALLOW THE SMALLER CIRCULATION TO LIFT NORTHEAST
LATE TONIGHT INTO WEDNESDAY MORNING. MOISTURE AXIS WILL SHIFT EAST
TOWARD NORTHWEST ZONES LATE TONIGHT. CAPE VALUES WILL INCREASE UP
TO 3KJ/KG LATE TONIGHT THROUGH WEDNESDAY MORNING FIELD WITH
VEERING WINDS FROM SURF TO 600MB BUT NOT GREAT WIND SPEEDS. WITH
THE LITTLE WAVE FORECASTED TO PULL NORTHEAST OVER ARKANSAS AND
MISSOURI WEDNESDAY MORNING...THE STRONGEST DYNAMICS WILL BE NORTH OF THE
AREA. WITH THIS PACKAGE...WE ARE THINKING SCATTERED CONVECTION...A
FEW STRONG STORMS WITH SMALL SUB SEVERE HAIL AND STRONG WINDS
WEDNESDAY MORNING FOR AREAS NORTH OF BTR.

OTHERWISE...SCATTERED CONVECTION ON WEDNESDAY AS THE FRONTAL
STRUGGLES TO APPROACH THE AREA. MOISTURE WILL REMAIN IN PLACE FOR
THURSDAY...SO WILL MAINTAIN CHANCE POPS. THE MAIN TROUGH WILL
DEEPEN ON THE EAST COAST FLOW PUSHING THE BULK OF THE DRY AIR JUST
EAST OF FORECAST...TRICKY TEMPERATURE FORECAST WITH FRONTAL
PASSAGE ACROSS EAST ZONES FRIDAY NIGHT AND RELATIVELY DEEPER MOISTURE
OVER WEST ZONES. ERGO...WILL MAINTAIN A SLIGHT CHANCE ACROSS BTR
AND SOME RIVER PARISHES ON FRIDAY. MAIN TROUGH WILL LIFT OFF THE
EAST COAST AND LEAVING RIDGE TO SLOWLY AMPLIFY OVER SOUTHERN TIER
OVER THE WEEKEND AT 5H...COOL AIR WILL SLIP UNDERNEATH THIS
FEATURE AND CREATE MORE STABLE ATM THROUGH THE WEEKEND.

&&

.AVIATION...

MOST AREAS WILL SEE A CLOUD DECK DEVELOPING IN THE FL010-FL020
RANGE BETWEEN 04 AND 06Z. COULD SEE BRIEF MVFR WITH PATCHY FOG
BETWEEN 08 AND 12Z WEDNESDAY MORNING. WITH WINDS WILL DECREASE
THIS EVENING TO 3 TO 7 KNOTS AT ALL TERMINALS WEDNESDAY MORNING.
CONDITIONS SHOULD IMPROVE AROUND 15Z WITH CEILINGS ALL ABOVE
FL020. CONVECTIVE DEVELOPMENT MAY BTR AND MCB AS EARLY AS 10Z
WEDNESDAY MORNING AND THE OTHER SITES BETWEEN 12 AND 18Z. 18

&&

.MARINE...

RIDGE OF HIGH PRESSURE CENTERED IN THE WESTERN ATLANTIC EXTENDS INTO
THE NORTHEAST GULF OF MEXICO. IT WILL SLOWLY RETREAT EAST THROUGH
WEDNESDAY. THIS WILL KEEP WINDS SOUTHEASTERLY AT 10 TO 15
KNOTS...POSSIBLY A TOUCH ABOVE 15 KNOTS BRIEFLY IN SPOTS. SEAS THRU
THAT PERIOD TO BE MAINLY IN THE 2 FOOT RANGE...WITH THE EXCEPTION OF
THE WESTERN WATERS WITH 3 TO 4 FOOT WAVES POSSIBLE TODAY WITH
PERSISTENT WINDS NEAR 15 KNOTS.

UPPER LEVEL TROUGH WILL DIG ACROSS THE EASTERN HALF BEGINNING MID
WEEK. THIS WILL BREAK DOWN RIDGE OVER THE GULF COAST AND CAUSE THE
WIND FIELD TO BREAKDOWN. A WEAK FRONTAL BOUNDARY WILL PASS THROUGH
EASTERN LEGS OF MARINE ZONES FRIDAY NIGHT WITH A WIND SHIFT TO
THE NORTH THROUGH THE FIRST HALF OF THE WEEKEND. 18

&&

.DECISION SUPPORT...
DSS CODE...BLUE.
DEPLOYED...NONE.
ACTIVATION...NONE.
ACTIVITIES...SLURRY SUPPORT.
             MONITORING RIVER FLOODING.

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  69  87  68  90 /  20  50  20  30
BTR  74  89  70  90 /  20  50  20  30
ASD  73  88  69  89 /  10  30  20  30
MSY  75  87  72  87 /  10  30  20  30
GPT  74  86  68  86 /  10  30  20  30
PQL  68  86  67  88 /  10  30  20  30

&&

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

$$