What is a heat burst?

AUSTIN (KXAN) — It is widely accepted information that, on the whole, the temperature goes down during the evening and nighttime hours. If they aren't dropping every hour it could be that they are holding steady. If they go up, it's not by much.But a rare event happened late Friday night in Burnet and Georgetown. And, it might have awakened you from a sound sleep.
The midnight temperature at Georgetown Municipal Airport was 83° with a humidity of 59%. The wind was out of the southwest