A top secret military rocket launch may create thunder-like noise in portions of the Mid Atlantic. According to NASA, the U.S. Navy will be involved in a training exercise at the NASA Wallops spaceport which will involve some kind of rocket launch.

“It may be visible from surrounding areas and could cause loud sounds, similar to thunder,” NASA Wallops cautioned.

However, due to the secrecy of the mission, there will be no livestream and no real-time updates. In fact, NASA and the U.S. Navy won’t even reveal the specific time or date of the launch, other than to say it will happen sometime on July 27 or 28.

NASA Wallops did say, though, once the lunch is complete, they will make an announcement stating so.

The Flight Facility at Wallops is operated by the Goddard Space Flight Center in Greenblet, Maryland. The spaceport, located on Wallops Island on the Eastern Shore of Virginia about 100 miles north-northeast of Norfolk, primarily serves to support science and exploration missions for NASA and other federal agencies.

Since its founding in 1945, there have been over 16,000 rockets launched from Wallops, with rockets of a wide range of shape and size launched. Some rockets have been as small as Super Loki meteorological rockets to orbital-class vehicles.