Tornado Warning 24, NWS New Orleans, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
946 PM CDT SUN OCT 15 2006

.UPDATE...
WILL BE UPDATING PACKAGE MAINLY TO BRING WATCHES IN LINE AND
UPDATED. THE MAIN CHANGE WILL BE AN UPGRADE OF THE COASTAL FLOOD
ADVISORY TO A COASTAL FLOOD WATCH FOR THE SAME AREA AROUND LAKES
PONTCHARTRAIN AND MAUREPAS AND ALONG THE MISSISSIPPI AND SOUTHEAST
LOUISIANA COAST. HAVE MADE SOME ADJUSTMENTS TO THE WINDS AS WELL.

THE UPCOMING 24 TO 36 HOURS WILL BECOME QUITE ACTIVE AS STRONG
WARM FRONTOGENESIS REGION IN THE GULF MOVES NORTHWARD. VAD WIND
PROFILERS AND 00Z SOUNDING WINDS SHOW STRONG TURNING IN THE LOWER
LEVELS INDICATIVE OF HIGH HELICITIES. THE SURFACE BOUNDARY SHOULD
MOVE ONSHORE AROUND 4 AM CDT WITH THE GREATEST SHEAR OCCURRING
JUST NORTH AND ALONG THIS BOUNDARY DURING THE MORNING HOURS. OUT
OF RESPECT FOR THE HIGH DIRECTIONAL AND SPEED SHEAR AND INCREASING
INSTABILITY...A VIABLE MARINE AIRMASS TORNADO THREAT APPEARS TO BE
MATERIALIZING. HEAVY RAINFALL ALSO SEEMS ON TRACK FOR THE WESTERN
HALF OF THE FORECAST AREA. UPDATES OUT SHORTLY.

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...COASTAL FLOOD WATCH THROUGH TUESDAY MORNING FOR LAZ038-LAZ040-
     LAZ050-LAZ058-LAZ060-LAZ061-LAZ062-LAZ064-LAZ066-LAZ067-
     LAZ068-LAZ069-LAZ070.

     SMALL CRAFT ADVISORY UNTIL 7 AM CDT TUESDAY FOR LAZ066.

     FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR LAZ034-LAZ035-
     LAZ036-LAZ037-LAZ038-LAZ046-LAZ047-LAZ048-LAZ049-LAZ050.

GM...SMALL CRAFT ADVISORY UNTIL 7 AM CDT TUESDAY FOR GMZ550-GMZ555-
     GMZ570-GMZ575.

     SMALL CRAFT ADVISORY UNTIL 1 AM CDT TUESDAY FOR GMZ530.

MS...COASTAL FLOOD WATCH THROUGH TUESDAY MORNING FOR MSZ080-MSZ081-
     MSZ082.

     FLASH FLOOD WATCH THROUGH TUESDAY MORNING FOR MSZ068-MSZ069-
     MSZ070.

GM...SMALL CRAFT ADVISORY UNTIL 7 AM CDT TUESDAY FOR GMZ550-GMZ555-
     GMZ570-GMZ575.

     SMALL CRAFT ADVISORY UNTIL 1 AM CDT TUESDAY FOR GMZ530.

&&

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HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1031 PM CDT SUN OCT 15 2006

LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-170345-
POINTE COUPEE-WEST FELICIANA-EAST FELICIANA-ST. HELENA-TANGIPAHOA-
WASHINGTON-ST. TAMMANY-IBERVILLE-WEST BATON ROUGE-
EAST BATON ROUGE-ASCENSION-LIVINGSTON-ASSUMPTION-ST. JAMES-
ST. JOHN THE BAPTIST-UPPER LAFOURCHE-ST. CHARLES-UPPER JEFFERSON-
ORLEANS-UPPER PLAQUEMINES-UPPER ST. BERNARD-UPPER TERREBONNE-
LOWER TERREBONNE-LOWER LAFOURCHE-LOWER JEFFERSON-
LOWER PLAQUEMINES-LOWER ST. BERNARD-WILKINSON-AMITE-PIKE-WALTHALL-
PEARL RIVER-HANCOCK-HARRISON-JACKSON-
1031 PM CDT SUN OCT 15 2006

THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF SOUTHEAST
LOUISIANA AND SOUTHERN MISSISSIPPI.

.DAY ONE...TONIGHT

.SEVERE THUNDERSTORMS...
STRONG WIND SHEAR IN THE LOWER LEVELS OF THE ATMOSPHERE ALONG A
STRONG WARM FRONT MOVING NORTH OUT OF THE GULF OF MEXICO WILL BE
CONDUCIVE TO SEVERE THUNDERSTORM DEVELOPMENT. THERE IS A SLIGHT
RISK OF SEVERE THUNDERSTORMS LATER TONIGHT AND MONDAY MORNING. THE
PRIMARY THREAT WILL BE ISOLATED TORNADOES DEVELOPING FROM
STRONGLY ROTATING STORMS MOVING OUT OF THE COASTAL AREAS. DAMAGING
WINDS AND PERIODS OF VERY HEAVY RAINFALL CAN ALSO OCCUR PRIMARILY
AFTER 4 AM MONDAY.

.FLOODING...
A FLOOD WATCH IS IN EFFECT FOR THE EAST-CENTRAL AND SOUTH-
CENTRAL PARISHES OF LOUISIANA...INCLUDING THE GREATER BATON ROUGE
AREA. THE GREATEST THREAT OF FLOODING RAINS WILL BE GENERALLY
AFTER 3 AM MONDAY...CONTINUING INTO MONDAY EVENING.

.MARINE HAZARDS...
A COASTAL FLOOD WATCH IS IN EFFECT UNTIL TUESDAY
MORNING FOR THE MISSISSIPPI AND SOUTHEAST LOUISIANA COAST.
ABNORMALLY HIGH TIDES OF 2 FEET ABOVE NORMAL CAN BE EXPECTED. THIS
MAY CAUSE SOME FLOODING OF LOW LYING COASTAL AREAS...PARTICULARLY
DURING THE DAILY HIGH TIDE PERIOD DURING THE MORNING HOURS.

A SMALL CRAFT ADVISORY IS IN EFFECT FOR ROUGH SEAS AND STRONG EAST
WINDS.

.DAYS TWO THROUGH SEVEN...MONDAY THROUGH SATURDAY

WIDESPREAD RAIN AND THUNDERSTORMS WILL CONTINUE MONDAY INTO TUESDAY
ACROSS THE AREA...AS A SLOW MOVING AREA OF LOW PRESSURE PASSES
THROUGH THE TENNESSEE VALLEY. A SLIGHT RISK OF SEVERE
THUNDERSTORMS WILL CONTINUE MONDAY INTO MONDAY NIGHT. THE MAIN
THREAT FROM ANY THUNDERSTORMS WILL BE VERY HEAVY
RAINFALL...FREQUENT LIGHTNING...STRONG WINDS...AND ISOLATED
TORNADOES. RAINFALL AMOUNTS OF 2 TO 3 INCHES ARE POSSIBLE WITH THE
HEAVIEST THUNDERSTORMS...WITH TOTAL RAINFALL AMOUNTS OF 4 TO 6
INCHES POSSIBLE ACROSS THE REGION BY TUESDAY MORNING. LOCALIZED
FLOODING OF LOW LYING AREAS AND STREETS WILL BE POSSIBLE.

STRONG SOUTHEAST WINDS OF 20 TO 30 KNOTS OVER THE COASTAL WATERS
WILL CONTINUE TO PROMPT SMALL CRAFT CONDITIONS THROUGH TUESDAY.
THESE WINDS WILL ALSO KEEP TIDE LEVELS HIGH ON SOUTH AND EAST
FACING SHORES WITH TIDES RUNNING UP TO 2 FEET ABOVE NORMAL. SOME
FLOODING OF COASTAL AREAS OUTSIDE OF HURRICANE PROTECTION LEVEES
WILL CONTINUE TO BE POSSIBLE.

SCATTERED THUNDERSTORMS ARE EXPECTED WEDNESDAY AND THURSDAY AS A
COLD FRONT SWEEPS THROUGH THE AREA. A FEW STRONG TO SEVERE
THUNDERSTORMS ARE POSSIBLE ON THURSDAY NEAR THE FRONT.

.SPOTTER INFORMATION STATEMENT...

SPOTTER ACTIVATION IS BEING REQUESTED FOR LATE TONIGHT AND
MONDAY...MAINLY IN THE LOUISIANA COASTAL PARISHES BEFORE DAYBREAK
AND IN THE NEW ORLEANS AND BATON ROUGE METRO AREAS FROM DAYBREAK
THROUGH MONDAY. LAW ENFORCEMENT AGENCIES AND FIRST RESPONDERS
SHOULD PLAN ACCORDINGLY FOR AN EXTENDED PERIOD OF ACTIVE WEATHER.
PLEASE NOTIFY THE NATIONAL WEATHER SERVICE OFFICE IN SLIDELL
PROMPTLY IF SEVERE WEATHER OCCURS IN YOUR AREA.

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