Alert archive / Louisiana / Special Marine Warnings in 2021
Special Marine Warning 21, NWS New Orleans, LA
NWS New Orleans, LA issued this special marine warning at Feb 15, 2021, 9:14 AM CST. It was in force for 61 min. No storm report in the archive falls inside the area while it was in force.
The area
The outline as issued.
The facts
- Issued
- Feb 15, 2021, 9:14 AM CST (15:14 UTC)
- Expired
- Feb 15, 2021, 10:15 AM CST
- In force
- 61 min
- Issued by
- NWS New Orleans, LA
- Area
- Storm-based polygon
- Hail
- 0.0 in
- Wind
- 34.0 mph
The nearest sounding before it
Slidell Radar S, LA (KSIL), launched 12:00Z, 3.2 hours before the alert went out and 147 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
- 20 J/kg
- Mixed-layer CIN
- 0 J/kg
- Mixed-layer LCL
- 319 m above ground
- 0-6 km bulk shear
- 67 kt
- 0-1 km storm-relative helicity
- 461 m²/s²
- 0-3 km storm-relative helicity
- 590 m²/s²
- Significant tornado parameter
- 0.0
- Supercell composite
- 0.2
The text
As transmitted.
091
WHUS54 KLIX 151514
SMWLIX
GMZ552-555-151615-
/O.NEW.KLIX.MA.W.0021.210215T1514Z-210215T1615Z/
BULLETIN - IMMEDIATE BROADCAST REQUESTED
Special Marine Warning
National Weather Service New Orleans LA
914 AM CST Mon Feb 15 2021
The National Weather Service in New Orleans has issued a
* Special Marine Warning for...
Coastal Waters from Boothville LA to Southwest Pass of the
Mississippi River out 20 nm...
Coastal waters from the Southwest Pass of the Mississippi River to
Port Fourchon Louisiana out 20 NM...
* Until 1015 AM CST.
* At 912 AM CST, a strong thunderstorm was located 9 nm southeast of
Southwest Pass Of the Mississippi River, moving northeast at 20
knots.
HAZARD...Wind gusts 34 knots or greater and small hail.
SOURCE...Radar.
IMPACT...Expect wind gusts in excess of 34 knots and suddenly
higher waves. Boats could sustain damage or capsize. Make
sure all on board are wearing life jackets. Return to
safe harbor if possible.
* Locations impacted include...
Southwest Pass Of the Mississippi River.
LAT...LON 2863 8936 2899 8955 2913 8929 2910 8921
2908 8923 2907 8921 2903 8918 2905 8918
2905 8919 2909 8920 2906 8911 2911 8907
2911 8905 2915 8903 2888 8874
TIME...MOT...LOC 1512Z 239DEG 20KT 2884 8928
HAIL...0.00IN
WIND...>34KTS
$$
BL3 follow-up statements
023
FZUS74 KLIX 151524
MWSLIX
Marine Weather Statement
National Weather Service New Orleans LA
924 AM CST Mon Feb 15 2021
GMZ552-555-151615-
/O.CON.KLIX.MA.W.0021.000000T0000Z-210215T1615Z/
924 AM CST Mon Feb 15 2021
...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 1015 AM CST...
For the following areas...
Coastal Waters from Boothville LA to Southwest Pass of the
Mississippi River out 20 nm...
Coastal waters from the Southwest Pass of the Mississippi River to
Port Fourchon Louisiana out 20 NM...
At 923 AM CST, a severe thunderstorm capable of producing waterspouts
was located 10 nm southeast of Southwest Pass Of the Mississippi
River, moving northeast at 20 knots.
HAZARD...Waterspouts, wind gusts 34 knots or greater, and small
hail.
SOURCE...Radar indicated.
IMPACT...Waterspouts can quickly form and capsize boats...damage
vessels and oil rigs...and create suddenly higher waves.
Make sure all on board are in a secure location and wearing
life jackets. Expect wind gusts in excess of 34 knots and
suddenly higher waves. Boats could sustain damage or
capsize. Make sure all on board are wearing life jackets.
Return to safe harbor if possible.
Locations impacted include...
Southwest Pass Of the Mississippi River.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to safe harbor until hazardous weather passes.
&&
LAT...LON 2868 8924 2904 8944 2913 8928 2910 8921
2908 8923 2907 8921 2903 8918 2905 8918
2905 8919 2909 8920 2906 8911 2911 8907
2911 8905 2915 8903 2912 8900 2912 8899
2888 8874
TIME...MOT...LOC 1523Z 239DEG 20KT 2887 8921
WATERSPOUT...POSSIBLE
HAIL...<.75IN
WIND...>34KTS
$$
BL832
FZUS74 KLIX 151550
MWSLIX
Marine Weather Statement
National Weather Service New Orleans LA
950 AM CST Mon Feb 15 2021
GMZ552-151559-
/O.CAN.KLIX.MA.W.0021.000000T0000Z-210215T1615Z/
950 AM CST Mon Feb 15 2021
...THE SPECIAL MARINE WARNING IS CANCELLED...
The affected areas were...
Coastal waters from the Southwest Pass of the Mississippi River to
Port Fourchon Louisiana out 20 NM...
The thunderstorm has moved out of the warned area and no longer
poses a significant threat to boaters.
LAT...LON 2880 8893 2899 8896 2904 8891 2888 8874
TIME...MOT...LOC 1549Z 239DEG 20KT 2895 8907
$$
GMZ555-151615-
/O.CON.KLIX.MA.W.0021.000000T0000Z-210215T1615Z/
950 AM CST Mon Feb 15 2021
...A SPECIAL MARINE WARNING REMAINS IN EFFECT UNTIL 1015 AM CST...
For the following areas...
Coastal Waters from Boothville LA to Southwest Pass of the
Mississippi River out 20 nm...
At 949 AM CST, a strong thunderstorm was located 17 nm east of
Southwest Pass Of the Mississippi River, moving northeast at 20
knots.
HAZARD...Wind gusts 34 knots or greater and small hail.
SOURCE...Radar indicated.
IMPACT...Expect wind gusts in excess of 34 knots and suddenly higher
waves. Boats could sustain damage or capsize. Make sure all
on board are wearing life jackets. Return to safe harbor if
possible.
The strong thunderstorm will remain over mainly open waters.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
Move to safe harbor until hazardous weather passes.
&&
LAT...LON 2880 8893 2899 8896 2904 8891 2888 8874
TIME...MOT...LOC 1549Z 239DEG 20KT 2895 8907
HAIL...<.75IN
WIND...>34KTS
$$
BL327 FZUS74 KLIX 151606 MWSLIX Marine Weather Statement National Weather Service New Orleans LA 1006 AM CST Mon Feb 15 2021 GMZ555-151615- /O.EXP.KLIX.MA.W.0021.000000T0000Z-210215T1615Z/ 1006 AM CST Mon Feb 15 2021 ...THE SPECIAL MARINE WARNING WILL EXPIRE AT 1015 AM CST... The affected areas were... Coastal Waters from Boothville LA to Southwest Pass of the Mississippi River out 20 nm... The thunderstorm has moved out of the area and no longer poses a significant threat to boaters. LAT...LON 2880 8893 2899 8896 2904 8891 2888 8874 TIME...MOT...LOC 1605Z 239DEG 20KT 2899 8898 $$ BL
The office that day
Everything else NWS New Orleans, LA issued on the same UTC day.
| Issued | Product | Office | Counties | Lasted |
|---|---|---|---|---|
| Feb 14, 7:17 PM CST | Hard Freeze Warning | LIX | East Feliciana, Pointe Coupee, Saint Helena, Tangipahoa, West Feliciana | 41 hr |
| Feb 14, 7:17 PM CST | Hard Freeze Warning | LIX | Assumption, East Baton Rouge, Iberville, Saint Bernard, Saint Helena, Saint James and 4 more | 41 hr |
| Feb 14, 7:17 PM CST | Wind Chill Advisory | LIX | Assumption, East Baton Rouge, East Feliciana, Iberville, Pointe Coupee, Saint Bernard and 7 more | 41 hr |
| Feb 14, 9:26 PM CST | Gale Warning | LIX | 17 hr | |
| Feb 14, 9:26 PM CST | Small Craft Advisory | LIX | 9 hr | |
| Feb 15, 7:06 AM CST | Special Weather Statement | LIX | Saint James | 24 min |
| Feb 15, 7:14 AM CST | Special Marine Warning | LIX | 61 min | |
| Feb 15, 8:17 AM CST | Special Marine Warning | LIX | 58 min | |
| Feb 15, 8:56 AM CST | Special Weather Statement | LIX | Plaquemines | 64 min |
| Feb 15, 9:45 AM CST | Special Marine Warning | LIX | 43 min | |
| Feb 15, 10:26 AM CST | Special Marine Warning | LIX | 37 min |
Nearby
Special Marine Warnings in Louisiana, 2021Every special marine warning in 2021
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.