Severe Thunderstorm Warning 46, NWS Lake Charles, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE LAKE CHARLES LA
644 AM CDT MON MAY 11 2015

.AVIATION...THE HIGH RESOLUTION SHORT RANGE MODEL TAKES THE BAND
OF SHOWERS AND THUNDERSTORMS APROACHING FROM THE NORTHWEST INTO
THE TERMINALS LATER THIS MORNING. POSSIBLE CONDITIONS AS LOW AS
LIFR CIGS WITH RAIN ASSUMING THE CURRENT ACTIVITY WEAKENS AS SOME
SIGNS HAVE INDICATED. SINCE ATMOSPHERE WOULD BE WORKED OVER BY THIS
AFTERNOON WILL GO WITH VFR CIGS WITH VCTS. LATE TNITE AS THE WEAK
FRONT APPROACHES, MVFR WITH LIGHT RAIN.

SWEENEY

&&

.PREV DISCUSSION... /ISSUED 343 AM CDT MON MAY 11 2015/

DISCUSSION...MAIN FORECAST ISSUE WILL BE POPS THROUGHOUT THE
WEEK.

LINE OF THUNDERSTORMS OVER NE TEXAS HAS SLOWLY SHIFTED SE DURING THE
NIGHT.  LATEST HRRR MAY BE A LITTLE QUICK IN PUSHING THE LINE INTO
NW PART OF THE FORECAST AREA BY 12Z...BUT THERE IS CERTAINLY
POTENTIAL FOR CONVECTION DEVELOPING AHEAD OF THE LINE BY THAT
TIME. EVEN IF LINE WEAKENS...REMNANT BOUNDARIES COMBINED WITH
RICH THTE AIR WILL LIKELY KEEP GOOD COVERAGE OF SHOWERS AND
THUNDERSTORMS FOR TODAY ESPECIALLY ACROSS EAST TEXAS AND CENTRAL
LOUISIANA. WILL TWEAK CURRENT POPS FORECAST FOR TODAY BUT OVERALL
NOT MUCH CHANGE FROM PREVIOUS FORECASTS.

FOR TUESDAY...MODELS SHOW VIGOROUS SHORTWAVE IN UPPER SW FLOW AND
THIS SHOULD FURTHER ENHANCE SHOWER AND THUNDERSTORM CHANCES.

A SERIES OF UPPER SHORT WAVE TROUGHS WILL MOVE THROUGH THE
WESTERN U.S. THROUGH THE WEEK. ALSO...MODELS ARE SHOWING A BROAD
NEGATIVELY TILTED TROUGH BECOMING ESTABLISHED OVER THE WEST COAST
BY LATE IN THE WEEK. AT THE SURFACE...FRONTAL BOUNDARY IS
FORECASTED TO MOVE INTO THE AREA AND STALL THROUGH AT LEAST
WEDNESDAY. A VERY MOIST AIRMASS WILL REMAIN IN PLACE THROUGH THE
WEEK. WILL THEREFORE MAINTAIN MAINLY DIURNAL SCATTERED SHOWERS AND
THUNDERSTORMS THROUGH THE REMAINDER OF THE WEEK. WILL LOWER POPS
SLIGHTLY OVER THE WEEKEND AS SURFACE BOUNDARY SHOULD BE LESS
DEFINED OR DIFFUSE.

MARINE....WILL ALLOW SCEC TO EXPIRE AT 5 AM FOR INNER AND OUTER
WATERS. WITH BOUNDARY APPROACHING THE AREA ON TUESDAY...GRADIENT
SHOULD WEAKEN AND LOW LEVEL FLOW SHOULD BECOME MORE EASTERLY.
PROGRESSION OF HIGH PRESSURE TOWARD THE EAST COAST WILL ALLOW FOR
A WEAK SOUTHERLY FLOW FOR THE REMAINDER OF THE WEEK.

04

&&

.PRELIMINARY POINT TEMPS/POPS...
AEX  84  68  79  65 /  60  70  70  30
LCH  83  71  83  70 /  50  50  70  30
LFT  86  72  84  70 /  40  40  60  30
BPT  83  72  82  71 /  50  60  70  30

&&

.LCH WATCHES/WARNINGS/ADVISORIES...
LA...NONE.
TX...NONE.
GM...NONE.
&&

AVIATION...11

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE LAKE CHARLES LA
414 AM CDT MON MAY 11 2015

GMZ430-432-435-450-452-455-470-472-475-LAZ027>033-041>045-052>055-
073-074-TXZ180-201-215-216-259>262-120915-
SABINE LAKE-CALCASIEU LAKE-VERMILION BAY-
COASTAL WATERS FROM CAMERON LA TO HIGH ISLAND TX OUT 20 NM-
COASTAL WATERS FROM INTRACOASTAL CITY TO CAMERON LA OUT 20 NM-
COASTAL WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY
LA OUT 20 NM-
WATERS FROM CAMERON LA TO HIGH ISLAND TX FROM 20 TO 60 NM-
WATERS FROM  INTRACOASTAL CITY TO CAMERON LA FROM 20 TO 60 NM-
WATERS FROM LOWER ATCHAFALAYA RIVER TO INTRACOASTAL CITY LA FROM
20 TO 60 NM-VERNON-RAPIDES-AVOYELLES-BEAUREGARD-ALLEN-EVANGELINE-
ST. LANDRY-CALCASIEU-JEFFERSON DAVIS-ACADIA-LAFAYETTE-
UPPER ST. MARTIN-VERMILION-IBERIA-ST. MARY-LOWER ST. MARTIN-
WEST CAMERON-EAST CAMERON-TYLER-HARDIN-JEFFERSON-ORANGE-
NORTHERN JASPER-NORTHERN NEWTON-SOUTHERN JASPER-SOUTHERN NEWTON-
414 AM CDT MON MAY 11 2015

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF THE NORTHWEST
GULF OF MEXICO...CENTRAL LOUISIANA...SOUTH CENTRAL LOUISIANA...
SOUTHWEST LOUISIANA...WEST CENTRAL LOUISIANA...EAST CENTRAL TEXAS
AND SOUTHEAST TEXAS.

.DAY ONE...TODAY AND TONIGHT
SCATTERED TO NUMEROUS SHOWERS AND THUNDERSTORMS ARE EXPECTED FOR
TODAY AND TONIGHT. THE BEST COVERAGE WILL LIKELY BE OVER EAST
TEXAS AND CENTRAL LOUISIANA. A FEW STRONG TO SEVERE STORMS WILL
BE POSSIBLE. LARGE HAIL AND WIND DAMAGE WILL BE THE MAIN THREATS.
LOCALLY HEAVY RAINFALL MAY OCCUR AS WELL WITH ISOLATED AMOUNTS IN
EXCESS OF 2 INCHES MAINLY OVER EAST TEXAS AND CENTRAL LOUISIANA.

.DAYS TWO THROUGH SEVEN...TUESDAY THROUGH SUNDAY
A SERIES OF UPPER LEVEL DISTURBANCES WILL MOVE THROUGH AREA ON
TUESDAY AND WEDNESDAY. A COOL FRONT WILL MOVE THE NEAR THE GULF
COAST AND WILL LIKELY STALL OVER THE REGION. THIS BRING NUMEROUS
SHOWERS AND THUNDERSTORMS FOR TUESDAY. WHILE A SEVERE STORM IS
POSSIBLE...FREQUENT LIGHTNING AND LOCALLY HEAVY RAINFALL WILL BE
THE MAIN HAZARDS.

WITH BOUNDARY STALLED OVER THE AREA FOR NEARLY THE REMAINDER OF
THIS WEEK...SCATTERED MAINLY DAYTIME SHOWERS AND THUNDERSTORMS ARE
EXPECTED THROUGH FRIDAY. THE ACTIVITY IS FORECASTED TO BECOME MORE
ISOLATED BY THE WEEKEND. FREQUENT LIGHTNING AND TORRENTIAL
RAINFALL WILL BE THE MAIN HAZARDS. THE THREAT FOR FLOODING WILL
LIKELY INCREASE GIVEN THE PROLONGED PERIOD FOR FORECASTED SHOWER
AND THUNDERSTORM ACTIVITY.

.SPOTTER INFORMATION STATEMENT...
SPOTTERS MAY BE NEEDED THROUGHOUT THE WEEK...ESPECIALLY FOR TODAY
THROUGH TUESDAY.