The National Weather Service already issues similar warnings for severe weather (tornado watches and PDS tornado watches, when ingredients are there for strong tornado outbreaks, etc.), and there is no requirement to evacuate, just suggestions that if you live in a mobile home or other non-durable structure you find temporary shelter. I assume messaging will be similar here with regard to ignition sources and having an evac plan.
This strikes me more as standardization than anything else. Curious whether issuance will be down to individual forecast offices or the Storm Prediction Center at a national level.
A few years ago, I thought the NWS was going to, or had, started giving atmospheric rivers categories 1-5 like tornados. I think in concept it is, as well as the new enhanced warnings, but the problem is when the conditions don’t materialize, and people begin to feel it’s all crying wolf.
Correct. The PDS language started with the severe wx products and is now being applied to Red Flags, as you state “standardization”. The PDS decision is done at the local office level and not by SPC.
So for what its worth the main push for adding the PDS language came from the Fire Agencies as a request to the NWS to delineate between more “routine” vs truly rare or historic events. Mainly as part of AARs after the 2017 wine country fires, 2019 October fires in NorCal/SoCal (Getty, Kincade, etc). The GACC decision makers needed a more clear understanding of the magnitude of the weather events to justify resource allocation and help Emergency Mangers/Sheriffs with Evac Order decisions. Nothing came out of the blue. It was collaboration, learning, growth and change rather than leaving things as status quo.
