An upper air disturbance combined with very unstable air to develop an isolated severe thunderstorm during the afternoon.
Every event with a place to put it. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS LIX wrote it up.
An upper air disturbance combined with very unstable air to develop an isolated severe thunderstorm during the afternoon.
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS New Orleans, LA wrote its last area forecast discussion before the first event at Jun 29, 3:06 PM CST, 24 minutes earlier.
AREA FORECAST DISCUSSION NATIONAL WEATHER SERVICE NEW ORLEANS LA 406 PM CDT WED JUN 29 2011 .SYNOPSIS... UPPER AIR ANALYSIS SHOWED THE HIGH OVER TEXAS PANHANDLE WITH A BROAD ANTICYCLONIC CIRCULATION OVER CENTRAL CONUS. IN ADDITION...TROUGH AXIS WAS NOTED FROM THE NORTHEAST CONUS TO NORTHEAST GULF. CYCLONIC CIRCULATION WAS ASSOCIATED WITH T.S. ARLENE OVER SOUTHWEST GULF. AT THE SURFACE...TROUGHS WERE LOCATED FROM THE MID ATLANTIC STATES TO THE NORTHEAST GULF...FOLLOWED BY A WEAK FRONTAL BOUNDARY FROM MID ATLANTIC STATES TO THE MID SOUTH. PW VALUES WERE 1.88 INCHES THIS MORNING...1.37 INCHES NEAR BIRMINGHAM AND 0.36 INCH OVER OHIO VALLEY. && .SHORT TERM... ON THE EDGES OF THE RIDGE HAS SEEN A FEW ISOLATED STORMS WEST NATCHEZ AS SOUNDING REVEALED SIMILAR CAPES 3500J/KG BUT 5H TEMPS INCREASED FROM -10C TO -7C AND COVERAGE MAY BE LESS THAN YESTERDAY. THROUGH FRIDAY...THE MAIN UPPER LEVEL HIGH WILL DRIFT EAST MAINTAINING NORTH TO NORTHEAST FLOW OVER THE FORECAST AREA. DRY AIR OVER OHIO VALLEY WILL BE TRANSPORTED SOUTHWEST OVER THE NORTHEAST PART OF THE FORECAST AREA THURSDAY INTO FRIDAY. 5H TEMPS WILL REMAIN BETWEEN -6C AND -8C AND RAIN CHANCES WILL DECREASE TO SLIGHT FRIDAY AND SATURDAY...BETTER CHANCES ALONG THE COAST AND RIVER PARISHES...ALL RELATIVE ON THE DRY SIDE. IN ADDITION...MANY SPOTS WILL EXPERIENCE HIGH TEMPS IN THE MID TO UPPER 90S THURSDAY...FRIDAY AND SATURDAY. .LONG TERM... UPPER LEVEL HIGH WILL CONTINUE TO PUSH EAST WITH THE RIDGE AXIS FROM THE MID SOUTH TO SOUTHERN GEORGIA. THIS WILL PLACE THE FORECAST AREA UNDER A DEEP CONTINENTAL EAST FLOW LATE SATURDAY THROUGH SUNDAY. PW VALUES WILL SLIGHTLY BELOW NORM FOR SHORT TIME SATURDAY BUT VALUES RETURNING TO NORM BY MONDAY. WITH THE RIDGE AXIS SITUATED FROM THE CENTRAL PLAINS TO NORTH FLORIDA...EAST TO SOUTHEAST FLOW WILL ALLOW DEEPER MOISTURE ACROSS THE GULF...NORTH GULF AND FORECAST AREA TUESDAY AND WEDNESDAY OF NEXT WEEK. WILL INCREASE RAIN CHANCES UP TO NORM FOR THIS PERIODS. TEMPS REMAINING NEAR TO SLIGHTLY ABOVE NORM FROM SATURDAY THROUGH NEXT WEEK. && .AVIATION... SCT CU FIELD WILL CONTINUE TO GIVE WAY ISLD TSRA AND AFFECT MCB...BTR AND POSSIBLY MSY THROUGH 00Z THU. DEEP NORTH TO NORTHEAST FLOW WILL BRING IN DRY AIR LATE TONIGHT AND FRIDAY...THUS DECREASING RAIN CHANCES TO SLIGHT AND ADDING HAZE TO MOST TAFS THROUGH 00Z SAT. OTHERWISE...VFR CONDITIONS WILL PREVAIL OUTSIDE OF CONVECTION. && .MARINE... SWELL GENERATED BY TROP STORM ARLENE OVER THE SOUTHERN GULF WILL CONTINUE TO MOVE INTO THE COASTAL WATERS THROUGH THURSDAY. WILL KEEP A LONG PERIOD SWELL IN THE FCAST AT 3 FEET. WITH SEVERAL SURFACE TROUGHS OVER THE AREA AND AN APPROACHING FRONT FROM THE NORTH....PRESSURE GRADIENT WILL REMAIN RELAXED OVER THE NORTHERN GULF LEADING TO VERY LIGHT WINDS SPEEDS AND NO WIND WAVE PRODUCTION...LENDING TO ONLY SWELL HEIGHTS TO MAKE UP THE TOTAL SEA CONDITIONS TONIGHT. WAVES SHOULD SUBSIDE OVER THE WEEKEND AS ARLENE MOVES INLAND AND PRESSURE GRADIENT REMAIN RELAXED THROUGH MONDAY. && .PRELIMINARY POINT TEMPS/POPS... MCB 71 95 71 96 / 20 10 10 10 BTR 74 97 74 95 / 20 20 10 10 ASD 72 95 74 94 / 20 20 20 10 MSY 75 94 77 93 / 20 20 20 20 GPT 73 94 75 93 / 20 20 20 10 PQL 70 97 72 94 / 20 10 20 10 && .LIX WATCHES/WARNINGS/ADVISORIES... LA...NONE. GM...NONE. MS...NONE. GM...NONE. &&
HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE NEW ORLEANS LA 611 AM CDT WED JUN 29 2011 GMZ530-532-534-536-538-550-552-555-557-570-572-575-577-LAZ034>037- 039-040-046>050-056>072-MSZ068>071-077-080>082-301115- LAKE PONTCHARTRAIN AND LAKE MAUREPAS-MISSISSIPPI SOUND- LAKE BORGNE-CHANDELEUR SOUND-BRETON SOUND- COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER OUT 20 NM- COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON OUT 20 NM- COASTAL WATERS FROM BOOTHVILLE LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20 NM- COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA OUT 20 NM- COASTAL WATERS FROM PORT FOURCHON TO LOWER ATCHAFALAYA RIVER FROM 20 TO 60 NM- COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON FROM 20 TO 60 NM- COASTAL WATERS FROM STAKE ISLAND LA TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60 NM- COASTAL WATERS FROM PASCAGOULA MS TO STAKE ISLAND LA FROM 20 TO 60 NM-POINTE COUPEE-WEST FELICIANA-EAST FELICIANA-ST. HELENA- 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-NORTHERN TANGIPAHOA- SOUTHERN TANGIPAHOA-WILKINSON-AMITE-PIKE-WALTHALL-PEARL RIVER- HANCOCK-HARRISON-JACKSON- 611 AM CDT WED JUN 29 2011 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF COASTAL WATERS OF SOUTHEAST LOUISIANA AND SOUTH MISSISSIPPI...SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI. .DAY ONE...TODAY AND TONIGHT ISOLATED TO SCATTERED SHOWERS AND THUNDERSTORMS OVER PORTIONS OF THE COASTAL AREAS AND COASTAL WATERS ARE EXPECTED TO DEVELOP INLAND THROUGH THE DAY...LEADING TO SCATTERED COVERAGE OF SHOWERS AND THUNDERSTORMS OVER MOST LAND AREAS IN THE AFTERNOON. A FEW THUNDERSTORMS MAY BECOME STRONG TO SEVERE WITH THE MAIN THREATS BEING STRONG...POSSIBLY DAMAGING WIND GUSTS OF 50 TO 60 MPH ALONG WITH FREQUENT LIGHTNING STRIKES. LOCALLY HEAVY RAINFALL COULD LEAD TO BRIEF PONDING OF WATER IN LOW LYING AREAS. THE ATCHAFALAYA RIVER REMAINS ABOVE FLOOD STAGE AT MORGAN CITY AND WILL CONTINUE TO FALL SLOWLY. REFER TO THE LATEST RIVER FLOOD STATEMENT FOR DETAILS. .DAYS TWO THROUGH SEVEN...THURSDAY THROUGH TUESDAY THUNDERSTORMS ARE EXPECTED TO BECOME MORE ISOLATED THURSDAY THROUGH SUNDAY. A FEW STRONG TO SEVERE THUNDERSTORMS WILL BE POSSIBLE THURSDAY...MAINLY DURING THE AFTERNOON AND EARLY EVENING HOURS...WITH THE MAIN THREATS BEING STRONG WINDS AND FREQUENT LIGHTNING. THE CHANCE OF THUNDERSTORMS MAY INCREASE SLIGHTLY ON INDEPENDENCE DAY AND TUESDAY. HEAT INDICES ARE EXPECTED TO REACH 100 TO 105 DEGREES AT TIMES DURING THE MIDDAY AND AFTERNOON HOURS EACH DAY. THE ATCHAFALAYA RIVER AT MORGAN CITY WILL BE IN MINOR FLOOD BUT CONTINUING TO RECEDE SLOWLY THROUGH TUESDAY. .SPOTTER INFORMATION STATEMENT... THE ACTIVATION OF STORM SPOTTERS...HAM RADIO OPERATORS...AND EMERGENCY MANAGEMENT PERSONNEL IN SUPPORT OF SEVERE WEATHER OPERATIONS IS NOT EXPECTED THROUGH TUESDAY...JULY 5TH. 22/TD
The national radar mosaic for the moment the first event began.
1 thunderstorm wind. Local standard time, as filed.
Trees were blown down near the intersection of U.S. Highway 61 and Louisiana Highway 54. One tree fell on a business.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Louisiana in 2011Every state in 2011This day in weather historyWarnings in Louisiana, June 2011
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 311077.