Alert archive / Louisiana / Severe Thunderstorm Warnings in 2009
Severe Thunderstorm Warning 83, NWS New Orleans, LA
NWS New Orleans, LA issued this severe thunderstorm warning at Apr 19, 2009, 5:09 AM CDT for Terrebonne Parish, Louisiana. It was in force for 36 min. No storm report in the archive falls inside the area while it was in force.
The area
The counties it named.
The facts
- Issued
- Apr 19, 2009, 5:09 AM CDT (10:09 UTC)
- Expired
- Apr 19, 2009, 5:45 AM CDT
- In force
- 36 min
- Issued by
- NWS New Orleans, LA
- Area
- Storm-based polygon
County Terrebonne Parish, LA
The nearest sounding before it
Lake Charles Mun, LA (KLCH), launched 00:00Z, 10.2 hours before the alert went out and 244 km from the middle of its area. This is the routine balloon launch nearest before it, the air the forecaster had in hand, not a measurement taken for the alert.
- Mixed-layer CAPE
- 1481 J/kg
- Mixed-layer CIN
- -11 J/kg
- Mixed-layer LCL
- 448 m above ground
- 0-6 km bulk shear
- 41 kt
- 0-1 km storm-relative helicity
- 260 m²/s²
- 0-3 km storm-relative helicity
- 345 m²/s²
- Significant tornado parameter
- 2.3
- Supercell composite
- 16.7
What forecasters said that day
The local office's own words before this severe thunderstorm warning went out, 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 this severe thunderstorm warning went out at Apr 19, 3:51 AM CDT, 1 hour 18 minutes earlier.
Area forecast discussion, Apr 19, 3:51 AM CDT, 1 hour 18 minutes before
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HAZARDOUS WEATHER OUTLOOK NATIONAL WEATHER SERVICE NEW ORLEANS LA 715 PM CDT SAT APR 18 2009 GMZ530-550-555-570-575-LAZ034>040-046>050-056>070-MSZ068>071-077- 080>082-200015- LAKE PONTCHARTRAIN AND LAKE MAUREPAS- COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO LOWER ATCHAFALAYA RIVER LA OUT 20 NM- COASTAL WATERS FROM PASCAGOULA MS TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20 NM- COASTAL WATERS FROM THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO LOWER ATCHAFALAYA RIVER LA FROM 20 TO 60 NM- COASTAL WATERS FROM PASCAGOULA MS TO THE SOUTHWEST PASS OF THE MISSISSIPPI RIVER FROM 20 TO 60 NM-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- 715 PM CDT SAT APR 18 2009 THIS HAZARDOUS WEATHER OUTLOOK IS FOR PORTIONS OF COASTAL WATERS OF SOUTHEAST LOUISIANA AND SOUTH MISSISSIPPI...SOUTHEAST LOUISIANA AND SOUTHERN MISSISSIPPI. .DAY ONE...TONIGHT THUNDERSTORMS AND HEAVY RAIN...A SLIGHT RISK OF SEVERE THUNDERSTORMS EXISTS FOR TONIGHT. THE STRONGEST THUNDERSTORM ACTIVITY WILL BE TONIGHT...AS A COLD FRONT PUSHES THROUGH THE AREA. RAINFALL AMOUNTS OF 1 TO 2 INCHES WILL BE COMMON WITH ISOLATED AMOUNTS IN EXCESS OF 3 INCHES POSSIBLE. IN ADDITION...ATMOSPHERIC PROFILES SUPPORT THE THREAT FOR DAMAGING WIND...HAIL...AND ISOLATED TORNADOES. RIVER FLOODING...SEVERAL AREA RIVERS REMAIN ABOVE FLOOD STAGE. REFER TO THE LATEST RIVER FLOOD STATEMENTS FOR DETAILED INFORMATION. MARINE...SMALL CRAFT ADVISORIES ARE IN EFFECT FOR ALL COASTAL WATERS INCLUDING THE TIDAL LAKES THROUGH TONIGHT DUE TO PERSISTENT SOUTHEAST WINDS OF 20 TO 25 KNOTS AND ROUGH SEAS. COASTAL FLOODING...TIDES WILL CONTINUE 1 TO 2 FEET ABOVE NORMAL AS A STRONG DEEP SOUTHERLY FETCH COUPLES WITH ABNORMALLY HIGH LUNAR TIDES TONIGHT. .DAYS TWO THROUGH SEVEN...SUNDAY THROUGH FRIDAY THUNDERSTORMS...ONGOING THUNDERSTORM ACTIVITY WILL CONTINUE TO IMPACT COASTAL MISSISSIPPI AND COASTAL SECTIONS OF SOUTHEAST LOUISIANA SUNDAY MORNING. THIS THUNDERSTORM ACTIVITY SHOULD QUICKLY MOVE OFFSHORE INTO THE COASTAL WATERS LATE SUNDAY MORNING INTO SUNDAY AFTERNOON...BEFORE CLEARING THE ENTIRE REGION SUNDAY NIGHT. A FEW OF THE THUNDERSTORMS COULD BE STRONG TO LOCALLY SEVERE SUNDAY MORNING...PRODUCING DAMAGING WINDS AND HEAVY RAIN. RIVER FLOODING...SEVERAL AREA RIVERS WILL REMAIN ABOVE FLOOD STAGE. REFER TO THE LATEST RIVER FLOOD STATEMENTS FOR DETAILED INFORMATION. .SPOTTER INFORMATION STATEMENT... SPOTTER ACTIVATION MAY BE REQUIRED TONIGHT AND INTO SUNDAY MORNING.
In the hours before
Special weather statement, Apr 19, 1:48 AM CDT, 3 hours 21 minutes before
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</html>The office that day
Everything else NWS New Orleans, LA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Apr 18, 8:36 PM CDT | Tornado Warning | LIX | Pointe Coupee | 24 min |
| Apr 18, 9:18 PM CDT | Tornado Warning | LIX | Pointe Coupee | 27 min |
| Apr 18, 11:12 PM CDT | Severe Thunderstorm Warning | LIX | East Baton Rouge, East Feliciana, Pointe Coupee, West Baton Rouge, West Feliciana | 33 min |
| Apr 18, 11:46 PM CDT | Severe Thunderstorm Warning | LIX | East Feliciana, Pointe Coupee, West Feliciana | 47 min |
| Apr 19, 12:02 AM CDT | Severe Thunderstorm Warning | LIX | East Baton Rouge, East Feliciana, Pointe Coupee, West Feliciana | 32 min |
| Apr 19, 2:57 AM CDT | Severe Thunderstorm Warning | LIX | Terrebonne | 33 min |
| Apr 19, 4:16 AM CDT | Severe Thunderstorm Warning | LIX | Lafourche, Terrebonne | 29 min |
| Apr 19, 4:26 AM CDT | Small Craft Advisory | LIX | 8 hr | |
| Apr 19, 4:40 AM CDT | Special Marine Warning | LIX | 65 min | |
| Apr 19, 4:44 AM CDT | Severe Thunderstorm Warning | LIX | Lafourche, Saint Charles | 31 min |
| Apr 19, 5:16 AM CDT | Special Marine Warning | LIX | 44 min | |
| Apr 19, 5:44 AM CDT | Special Marine Warning | LIX | 61 min | |
| Apr 19, 6:33 AM CDT | Special Marine Warning | LIX | 57 min | |
| Apr 19, 6:51 AM CDT | Special Marine Warning | LIX | 39 min | |
| Apr 19, 7:29 AM CDT | Special Marine Warning | LIX | 61 min | |
| Apr 19, 8:25 AM CDT | Special Marine Warning | LIX | 65 min | |
| Apr 19, 3:44 PM CDT | Small Craft Advisory | LIX | 15 hr |
Nearby
Severe Thunderstorm Warnings in Louisiana, 2009Every severe thunderstorm warning in 2009
Sources
The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive.