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.