A strong upper air trough moving through the lower Mississippi River Valley aided in the development of numerous thunderstorms, some of which became severe, during the morning hours of the 4th.

Marine Thunderstorm Wind in COASTAL WATERS FROM SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON LOUISIANA OUT 20 NM, GULF OF MEXICO
From 04-MAY-19 09:35:00 to 04-MAY-19 09:35:00 (CST-6)
Location: PORT FOURCHON STATION (PTFL1)
Magnitude: 37.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

The station at Port Fourchon Heliport reported a 37 knot wind gust during a thunderstorm.

Marine Thunderstorm Wind in LAKE PONCHARTRAIN AND LAKE MAUREPAS, GULF OF MEXICO
From 04-MAY-19 09:45:00 to 04-MAY-19 09:45:00 (CST-6)
Location: MID LAKE PONTCHARTRAIN
Magnitude: 47.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

The Weatherflow Mesonet observation at the midpoint of the Lake Pontchartrain Causeway reported a 54 mph wind gust in a thunderstorm.

Marine Thunderstorm Wind in COASTAL WATERS FROM PORT FOURCHON LOUISIANA TO LOWER ATCHAFALAYA RIVER LOUISIANA FROM 20 TO 60 NM, GULF OF MEXICO
From 04-MAY-19 08:15:00 to 04-MAY-19 08:15:00 (CST-6)
Location: SHIP SHOAL OIL PLATFORM (KSPR)
Magnitude: 34.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Station KSPR reported a 34 knot wind gust in a thunderstorm.

Marine Thunderstorm Wind in LAKE PONCHARTRAIN AND LAKE MAUREPAS, GULF OF MEXICO
From 04-MAY-19 09:53:00 to 04-MAY-19 09:53:00 (CST-6)
Location: LKFRNT ARPT NEW
Magnitude: 37.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS

Lakefront Airport reported a 37 knot wind gust in a thunderstorm.

Marine Thunderstorm Wind in LAKE BORGNE, GULF OF MEXICO
From 04-MAY-19 10:30:00 to 04-MAY-19 10:30:00 (CST-6)
Location: SHELL BEACH STATION (SHBL1)
Magnitude: 41.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: C-MAN Station

The C-MAN station at Shell Beach reported a 41 knot wind gust in a thunderstorm.

Marine Thunderstorm Wind in COASTAL WATERS FROM BOOTHVILLE LOUISIANA TO SOUTHWEST PASS OF THE MISSISSIPPI RIVER OUT 20 NM, GULF OF MEXICO
From 04-MAY-19 11:06:00 to 04-MAY-19 11:06:00 (CST-6)
Location: PILOTS STATION (PSTL1)
Magnitude: 40.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: C-MAN Station

Station PILL1 at Pilottown reported a 40 knot wind gust during a thunderstorm.

Marine Thunderstorm Wind in MISSISSIPPI SOUND, GULF OF MEXICO
From 04-MAY-19 12:36:00 to 04-MAY-19 12:36:00 (CST-6)
Location: PETIS BOIS ISLAND STATION (PTBM6)
Magnitude: 34.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: C-MAN Station

The C-MAN station PTBM6 at Petit Bois Island reported a 34 knot wind gust in a thunderstorm.

Marine Thunderstorm Wind in COASTAL WATERS FROM PASCAGOULA MISSISSIPPI TO STAKE ISLAND LOUISIANA FROM 20 TO 60 NM, GULF OF MEXICO
From 04-MAY-19 12:35:00 to 04-MAY-19 12:35:00 (CST-6)
Location: MAIN PASS 289 AWOS (KVKY)
Magnitude: 35.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

AWOS station KVKY in Main Pass Block 289C reported a 35 knot wind gust in a thunderstorm.

Marine Thunderstorm Wind in LAKE PONCHARTRAIN AND LAKE MAUREPAS, GULF OF MEXICO
From 04-MAY-19 09:50:00 to 04-MAY-19 09:50:00 (CST-6)
Location: NORTH LAKE PONTCHARTRAIN
Magnitude: 41.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

The Weatherflow Mesonet site at Mandeville reported a 47 mph wind gust in a thunderstorm.

Marine Thunderstorm Wind in COASTAL WATERS FROM SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON LOUISIANA OUT 20 NM, GULF OF MEXICO
From 04-MAY-19 10:00:00 to 04-MAY-19 10:00:00 (CST-6)
Location: GRAND ISLE STATION (GISL1)
Magnitude: 38.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: C-MAN Station

The C-MAN station at Grand Isle (GISL1) reported a 38 knot wind gust in a thunderstorm.

Waterspout in COASTAL WATERS FROM SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON LOUISIANA OUT 20 NM, GULF OF MEXICO
From 04-MAY-19 10:00:00 to 04-MAY-19 10:00:00 (CST-6)
Location: GRAND ISLE STATION (GISL1)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Broadcast Media

Broadcast media relayed a video of a waterspout near Grand Isle. Event time was estimated by radar.

Marine Thunderstorm Wind in COASTAL WATERS FROM SOUTHWEST PASS OF THE MISSISSIPPI RIVER TO PORT FOURCHON LOUISIANA FROM 20 TO 60 NM, GULF OF MEXICO
From 04-MAY-19 10:35:00 to 04-MAY-19 10:35:00 (CST-6)
Location: MISSISSIPPI CANYON OIL PLATFORM 311A (KMDJ)
Magnitude: 36.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: AWOS

Station KMDJ in Mississippi Canyon Block 311A reported a 36 knot wind gust in a thunderstorm.

Waterspout in MISSISSIPPI SOUND, GULF OF MEXICO
From 04-MAY-19 11:40:00 to 04-MAY-19 11:40:00 (CST-6)
Location: WEST PIER GULFPORT STATION (GWPM6)
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Emergency Manager

The Harrison County Emergency Manager relayed a report of a waterspout offshore south of Gulfport.

Marine Thunderstorm Wind in MISSISSIPPI SOUND, GULF OF MEXICO
From 04-MAY-19 11:41:00 to 04-MAY-19 11:41:00 (CST-6)
Location: SHIP ISLAND PASS STATION (SIPM6)
Magnitude: 36.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: Mesonet

The Weatherflow Mesonet station at Ship Island reported a 41 mph wind gust in a thunderstorm.

Marine Thunderstorm Wind in LAKE PONCHARTRAIN AND LAKE MAUREPAS, GULF OF MEXICO
From 04-MAY-19 06:13:00 to 04-MAY-19 06:13:00 (CST-6)
Location: LKFRNT ARPT NEW
Magnitude: 40.00 MG
Property damage: 0.00K
Crop damage: 0.00K
Reported by: ASOS