Battle of Los Angeles Anniversary: Weather Balloon Sparked Air Raid, UFO Scare

Coastal defense forces opened fire in 1942, mistaking a meteorological balloon for a Japanese attack.

Feb. 25, 2026 at 4:33pm

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On February 25, 1942, coastal defense forces in Los Angeles opened fire, fearing a Japanese attack. However, a military review later concluded that the likely cause was the launch of a meteorological weather balloon, which triggered the chaos and "war nerves" that led to the shooting. The incident remains a flashpoint for conspiracy theories, including claims of an alien spacecraft being captured.

Why it matters

The "Battle of Los Angeles" highlights the heightened wartime fears and tensions that existed in the U.S. shortly after the attack on Pearl Harbor. It also demonstrates how easily misidentified objects in the sky can spark panic and military responses, even when there is no actual threat.

The details

In the early hours of February 25, 1942, coastal defense forces in Los Angeles opened fire, believing they were under attack by the Imperial Japanese Army Air Force. A 1949 review by the United States Coast Artillery Association concluded that a meteorological balloon launched at 1:00 a.m. was the likely cause of "all the shooting". The official review explained that once the chaos began, frayed nerves and imagination resulted in defense forces creating "all kinds of targets in the sky". A later report by the US Office of Air Force History called it a case of "war nerves" triggered by a weather balloon and made worse by flares and shell bursts from other batteries.

  • On February 25, 1942, coastal defense forces in Los Angeles opened fire in the early hours of the morning.
  • At 1:00 a.m. on February 25, 1942, a meteorological balloon had been sent aloft, which was likely the cause of the shooting.
  • The incident took place less than 3 months after the U.S. entered World War II in response to the attack on Pearl Harbor.
  • The incident occurred only a day after a Japanese submarine opened fire on the California coast near Santa Barbara.

The players

United States Coast Artillery Association

The organization that conducted a 1949 review of the incident and concluded a meteorological balloon was the likely cause.

U.S. Office of Air Force History

The organization that later called the incident a case of "war nerves" triggered by a weather balloon.

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What they’re saying

“A meteorological balloon had been sent aloft at 1:00 a.m. and was the likely cause of "all the shooting".”

— United States Coast Artillery Association, Review of the incident

“Once the chaos began, frayed nerves and imagination resulted in defense forces creating "all kinds of targets in the sky".”

— United States Coast Artillery Association, Review of the incident

“It was a case of "war nerves" triggered by a weather balloon and made worse by flares and shell bursts from other batteries.”

— U.S. Office of Air Force History, Report on the incident

The takeaway

The "Battle of Los Angeles" highlights the heightened wartime fears and tensions that existed in the U.S. shortly after the attack on Pearl Harbor, and demonstrates how easily misidentified objects in the sky can spark panic and military responses, even when there is no actual threat.