8/5 Update: A UFO was spotted in a thunderstorm in Houston a few days later.
A Texas UFO Sightings reader saw the sky light up - however it did not appear to be lightning. No sound, no thunder, and no storm. Here's a screenshot from the video took:
And the video, as well as testimony, he graciously shared with the site:
The sky is lighting up all around...almost like lightning but no thunder and no storm...never seen anything like it.