Severe thunderstorm warnings, flash flood watches, wind advisories...
Anytime the National Weather Service issues a watch, warning, or advisory, they do so becuase certain pre-determined criteria have been met, or will be met soon.
For example, consider a severe thunderstorm warning. Meteorologists at the National Weather Service don't just see a strong storm on radar and decide to issue a warning. It's much more complicated than that. In order to be considered severe, a thunderstorm must meet at least one of these three criteria...
- Winds 58 mph or greater
- Hail 3/4" in diameter or larger
- Tornado (pretty obvious, right?)
Likewise, certain criteria have to be met (or expected) in order for the National Weather Service to issue a heat advisory or an excessive heat warning -- and those criteria have just been changed.
After reviewing past weather data and consulting with local health officials, the National Weather Service office in St. Louis has adopted new criteria to be used for the issuance of heat-related advisories and warnings. As the hot and humid days of summer approach, it's time to get back into a summer weather safety state of mind.
Check out the new criteria established by our friends at the local National Weather Service office, and get ready for the dog days of summer -- they'll be here before you know it!