Moderate to heavy rain with a flooding risk will continue for northern and central California, with heavy mountain snow in the Sierras, southern Cascades, and northern Rockies through Friday. A series of winter storms will track from the Upper Midwest to off the Northeast U.S. coast into next week bringing rounds of moderate to locally heavy rain south of their track and ice and snow to the north. Read More >
Biggest takeaway:
This is a rare event, but one that needs to be planned for given its catastrophic potential. Any plan will likely revolve around near instant notification of all people with a canned, prepared statement of what can be done to take cover very quickly. This plan should be able to link to your Tornado Warning plan (the "threat" listed just above this one) to enhance actions (hopefully) already taken from the NWS tornado warning that likely was already issued.
Warning/Trigger for Plan:
Either:
A) NWS Tornado Warning mentioning “CONFIRMED” tornado.
B) Sighted tornado from your location
Advance Notice/Time to Activate & Accomplish Your Planned Response:
Plan on 0-2 minutes of advance warning
Allow options that there may be as much as 10 mins if a NWS Tornado Warning contains confirmation of a tornado [uncommon].
Frequency:
Rare, but a high end threat that needs to have a plan to allow proper response.
How Accurate Warnings?
If a tornado is confirmed in a warning, or you see one - the threat is there. It will just be a matter of if it will hit your exact location. Race to do what you can.