Widespread showers and thunderstorms across much of the central and eastern U.S. will produce areas of excessive rainfall, especially in the southern Mid-Atlantic states. Scattered severe thunderstorms are expected from Montana into portions of the central/southern Plains this weekend. A heatwave will build in the Desert Southwest, in parts of Arizona, southeastern California, and southern Nevada. Read More >
Biggest takeaway:
Whatever plan you base off a tornado warning, that NWS tornado warning needs to be received instantly, & your plan triggered and accomplished rapidly (within a few minutes) to be of value.
Warning/Trigger for Plan:
NWS Tornado Warning
Advance Notice/Time to Activate & Accomplish Your Planned Response:
Plan on 5-10 minutes of advance warning.
Allow options that there may be little/no advance warning, and it may be as much as 30 mins.
Frequency:
Average is 0-2/year for any one location in this region.
How Accurate Warnings?
If a tornado occurs, it is highly likely that it was preceded by at least a few minutes by a NWS Tornado Warning. That said, with the current state of the science, more than half of NWS Tornado Warnings are false alarms. Furthermore, even when a tornado does occur within a warning area, it is less likely to hit your specific location.