Mylar balloon causes temporary power outage St. Louis Airport

By First Alert 4 Staff

Published: Jun. 8, 2025 at 3:23 PM CDT|Updated: 5 hours ago

ST. LOUIS, Mo. (First Alert 4) - A temporary power outage Sunday in a part of St. Louis Lambert International Airport was caused by a Mylar balloon, according to Ameren.

According to a spokesperson for Lambert, power was out for about four minutes Sunday morning until their generators started. Terminal 2, which houses Southwest Airlines, was the main area impacted by the outage. Southwest Airlines tells First Alert 4 there were minor delays, but operations have resumed as normal.

Ameren tells First Alert 4 the outage was caused by a balloon tripping a feed into one of their substations that serves the airport. As of 3 p.m., the airport has full power.

Mylar balloons, which are metallic, can cause power outages due to the fact that they can conduct electricity. Ameren encourages people not to release Mylar balloons outdoors.