Got to agree with you there RMC.
The commonly-accepted rule to keep your flight from developing into 'thriller' proportions is to avoid by at
least 20NM, any thunderstorm that's identified as severe or giving an intense radar echo.
The same avoidance distance should also be applied if you can't clear the top of a known or suspected severe thunderstorm by at least 10,000 feet.
Honeywell agrees with the 20NM avoidance distance, and also provides advice that thunderstorm with tops >35,000 ft should be treated as
severe.
