Flash Flood Warning 7, NWS New Orleans, LA

AREA FORECAST DISCUSSION
NATIONAL WEATHER SERVICE NEW ORLEANS LA
320 AM CDT FRI OCT 27 2006

.DISCUSSION...

EARLY THIS MORNING THE SURFACE LOW WAS OVER EASTERN OKLAHOMA WITH
A WARM FRONT EXTENDING INTO EAST-CENTRAL LOUISIANA AND THE COLD
FRONT SOUTHWARD ACROSS EAST TEXAS. EXTENSIVE LIGHT TO MODERATE
SHOWERS/THUNDERSTORMS CONTINUE TO TRAIN ACROSS SOUTHWEST
MISSISSIPPI AND PORTIONS OF EAST-CENTRAL LOUISIANA. THIS IS
LEADING TO SOME LOCALIZED FLOODING...THEREFORE THE FLASH FLOOD
WATCH WILL BE CONTINUED THROUGH THIS MORNING. MODELS GENERALLY
AGREE ON PUSHING THE FRONT THROUGH MOST OF THE AREA BY EARLY
AFTERNOON AND THEN THROUGH COASTAL MISSISSIPPI THIS AFTERNOON.
THERE REMAINS ENOUGH INSTABILITY IN THE AREA FOR THE POTENTIAL OF
SOME SEVERE STORMS WITH DAMAGING WINDS INTO THE MORNING HOURS.
THANKFULLY WE DONT STILL HAVE THE 603 M2/S2 0-3KM SR HELICITY THAT
WE DID YESTERDAY MORNING AT LIX. THE THREAT OF FLOODING CONTINUES
AHEAD OF THE FRONTAL PASSAGE LATER TODAY. SOME LIGHT SHOWER
ACTIVITY MAY CONTINUE BEHIND THE FRONT THIS AFTERNOON AS THE
UPPER-LEVEL TROUGH MOVES ACROSS THE AREA. BEHIND THIS
SYSTEM...WINDS WILL REMAIN STRONG OUT OF THE NORTHWEST INTO
SATURDAY MORNING AND KEEP SMALL CRAFT ADVISORIES IN THE COASTAL
WATERS. THE REST OF THE WEEKEND INTO HALLOWEEN LOOK TO BE FAIRLY
MILD AS SURFACE HIGH PRESSURE SLIDES EASTWARD ACROSS THE GULF
COAST. RAIN CHANCES RETURN BY THE MIDDLE OF NEXT WEEK WITH THE
RETURN FLOW AND A SURFACE LOW DEVELOPING OVER THE LOWER
MISSISSIPPI VALLEY TO TENNESSEE VALLEY.

&&

.PRELIMINARY POINT TEMPS/POPS...
MCB  73  49  71  45 /  80   5   0   0
BTR  74  50  71  47 /  80   5   0   0
MSY  79  55  71  52 /  90   5   0   0
GPT  77  51  71  47 / 100   5   0   0

&&

.LIX WATCHES/WARNINGS/ADVISORIES...
LA...FLASH FLOOD WATCH UNTIL NOON CDT TODAY FOR LAZ034-LAZ035-LAZ036-
     LAZ037-LAZ038-LAZ039-LAZ046-LAZ047-LAZ048-LAZ049-LAZ050.

GM...SMALL CRAFT ADVISORY UNTIL 1 PM CDT SATURDAY FOR GMZ530-GMZ550-
     GMZ555-GMZ570-GMZ575.

MS...FLASH FLOOD WATCH UNTIL NOON CDT TODAY FOR MSZ068-MSZ069-MSZ070-
     MSZ071.

GM...SMALL CRAFT ADVISORY UNTIL 1 PM CDT SATURDAY FOR GMZ530-GMZ550-
     GMZ555-GMZ570-GMZ575.

&&

25

HAZARDOUS WEATHER OUTLOOK
NATIONAL WEATHER SERVICE NEW ORLEANS LA
619 PM CDT THU OCT 26 2006

LAZ034>040-046>050-056>070-MSZ068>071-077-080>082-272330-
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-
619 PM CDT THU OCT 26 2006

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

.DAY ONE...TONIGHT

SEVERE WEATHER...
THUNDERSTORMS EMBEDDED WITHIN AN EASTWARD MOVING SQUALL LINE ARE
EXPECTED TO IMPACT THE FAR WESTERN HALF OF THE OUTLOOK AREA LATE
TONIGHT. THERE IS A POSSIBILITY OF STRONG TO SEVERE THUNDERSTORMS
DEVELOPING WITHIN THE SQUALL LINE WITH THE MAIN THREAT BEING
DAMAGING WINDS. ISOLATED TORNADOES MAY ALSO OCCUR WITH
THUNDERSTORMS THAT DEVELOP AHEAD OF THE SQUALL LINE.

FLASH FLOODING...
HEAVY RAINFALL WILL BE POSSIBLE ACROSS THE NORTHWESTERN THIRD OF THE
OUTLOOK AREA LATER TONIGHT. RAINFALL AMOUNTS FROM 1 TO 3 INCHES
WITH LOCALLY HIGHER AMOUNTS WILL BE POSSIBLE ACROSS PORTIONS OF
EAST CENTRAL AND SOUTHEAST LOUISIANA AND ACROSS EXTREME SOUTHWEST
MISSISSIPPI. FLASH FLOODING IS POSSIBLE ACROSS THESE AREAS LATE
TONIGHT WHERE HEAVY RAINFALL DEVELOPS.

MARINE HAZARDS...
A SMALL CRAFT ADVISORY IS IN EFFECT TONIGHT FOR THE GULF COASTAL
WATERS AND TIDAL LAKES FOR STRONG SOUTHERLY WINDS DEVELOPING AHEAD
OF THE COLD FRONT.

.DAYS TWO THROUGH SEVEN...FRIDAY THROUGH WEDNESDAY

STRONG TO SEVERE THUNDERSTORMS REMAIN POSSIBLE EARLY FRIDAY AS AN
EXPECTED SQUALL LINE CONTINUES EASTWARD ACROSS THE CENTRAL AND
EASTERN HALF OF THE OUTLOOK AREA. DAMAGING WINDS REMAIN THE
PRIMARY THREAT ALTHOUGH ISOLATED TORNADOES CANNOT BE RULED OUT
FOR STORMS THAT DEVELOP AHEAD OF THE SQUALL LINE. HEAVY RAINFALL
RESULTING IN FLASH FLOODING ALSO REMAINS POSSIBLE FRIDAY MORNING OVER
THE NORTHWESTERN THIRD OF THE OUTLOOK AREA. THE COLD FRONT AND
ASSOCIATED SQUALL LINE ARE EXPECTED TO MOVE EAST OF THE OUTLOOK
AREA BY FRIDAY AFTERNOON WITH RAIN TAPERING OFF BY FRIDAY EVENING.

SMALL CRAFT ADVISORIES WILL ALSO CONTINUE ACROSS THE GULF COASTAL
WATERS AND TIDAL LAKES FRIDAY INTO SATURDAY MORNING AS STRONG
NORTHERLY FLOW DEVELOPS BEHIND THE EXITING COLD FRONT. WINDS AND
SEAS ARE EXPECTED TO DIMINISH LATE SATURDAY AND SATURDAY NIGHT.

.SPOTTER INFORMATION STATEMENT...

THE ACTIVATION OF STORM SPOTTERS...HAM RADIO OPERATORS AND EMERGENCY
MANAGEMENT PERSONNEL IN SUPPORT OF SEVERE WEATHER OPERATIONS MAY BE
NECESSARY FOR LATE TONIGHT AND FRIDAY MORNING. FIRST RESPONSE AGENCIES
ARE URGED TO MONITOR THE DEVELOPING WEATHER SITUATION AND STAFF
ACCORDINGLY IF WARRANTED. IN ADDITION...FIRST RESPONSE AGENCIES
ARE REQUESTED TO SUBMIT ANY REPORTS OF SEVERE WEATHER TO THE
NATIONAL WEATHER SERVICE IF TIME PERMITS.

SPECIAL WEATHER STATEMENT
NATIONAL WEATHER SERVICE NEW ORLEANS LA
1104 PM CDT THU OCT 26 2006

LAZ034>039-046>050-MSZ068>071-270549-
AMITE-ASCENSION-EAST BATON ROUGE-EAST FELICIANA-IBERVILLE-LIVINGSTON-
PIKE-POINTE COUPEE-ST HELENA-TANGIPAHOA-WALTHALL-WASHINGTON-
WEST BATON ROUGE-WEST FELICIANA-WILKINSON-
1104 PM CDT THU OCT 26 2006

...A STEADY RAIN CONTINUES...

A LARGE AREA OF RAIN WILL CONTINUE TO MOVE ACROSS SOUTHWEST AND SOUTH
MISSISSIPPI AND EAST CENTRAL LOUISIANA THROUGH MIDNIGHT. PARTS OF
WILKINSON COUNTY...POINTE COUPEE AND WEST FELICIANA PARISHES HAVE
ALREADY RECEIVED AROUND 3 TO 4 INCHES OF RAIN SINCE THIS AFTERNOON.
IN ADDITION...MANY AREAS IN THE FLASH FLOOD WATCH AREA HAVE RECEIVED
1 TO 2 INCHES OF RAIN SINCE THIS AFTERNOON.

THE MODERATE RAINFALL WILL CONTINUE TO SLOWLY SATURATE SOILS AROUND
THE BATON ROUGE METRO AREA AND SOUTH MISSISSIPPI. EXCESSIVE RAINWATER
RUNOFF IS POSSIBLE OVERNIGHT WITH HEAVY RAINFALL FROM STRONG
THUNDERSTORMS.

STAY TUNED TO NOAA WEATHER RADIO...COMMERCIAL RADIO OR TELEVISION
STATIONS...OR YOUR CABLE TELEVISION PROVIDER FOR LATER STATEMENTS
CONCERNING THIS POTENTIALLY DANGEROUS FLASH FLOOD THREAT.

18