The guy lives in San Diego. San Diego is one of only about 60 locations in the contiguous US that launches weather balloons. They are launched twice a day at 0000 and 1200 UTC. For San Diego that is 5 AM and 5 PM. It takes an hour to an hour and a half for them to reach the altitude where they normally burst. They normally burst at or above 100,000 feet.
http://weather.uwyo.edu/upperair/naconf.html
The same guy has also posted videos of a "chembomb" exploding (it was a weather balloon popping) and a UFO flying in front of the Moon (it was a bird).