The Paradise fire once again underscored shortcomings in warning systems.

Gov. Jerry Brown signed a bill in September requiring the development of statewide guidelines for Amber Alert-like warnings. A few Northern California communities are moving to install sirens after wine country residents complained they didn't receive warnings to evacuate ahead of a deadly wildfire in October 2017 that destroyed 5,300 homes.

In 2008, the pair of wildfires that menaced Paradise destroyed 130 homes. No one was seriously hurt, but the chaos highlighted the need for a plan.

Paradise sits on a ridge between two higher hills, with only one main exit out of town. The best solution seemed to be to order evacuations in phases, so people didn't get trapped.

"Gridlock is always the biggest concern," said William Stewart, a forestry professor at the University of California, Berkeley.

Authorities developed an evacuation plan that split the town of 27,000 into zones and called for a staggered exodus. Paradise even conducted a mock evacuation during a morning commute, turning the main thoroughfare into a one-way street out of town.

Last week, when a wind-whipped fire bore down on the town, the sheriff's department attempted an orderly, phased evacuation, instead of blasting a cellphone alert over an entire area.

Phil John, chairman of the Paradise Ridge Fire Safe Council, defended the evacuation plan he helped develop. John said that the wildfire this time was exceptionally fast-moving and hot, and that no plan was going to work perfectly.

When the fire reached the eastern edge of Paradise, six zones were ordered to clear out about 8 am But almost simultaneously, the gusting winds were carrying embers the size of dinner plates across town, and structures were catching fire throughout the city. Less than an hour later, the entire town was ordered evacuated.

"It didn't work perfectly," John said Thursday. "But no one could plan for a fire like that." Likewise, Stewart, the forestry professor, said the wildfire that hit Paradise disrupted the orderly evacuation plan because it "was moving too fast. All hell broke loose." Satellite images show half the town on fire less than two hours after the first evacuation order.

Stewart said experts continue to debate how best to issue evacuation orders, and no ideal solution has been found.

At the other end of the state, meanwhile, crews continued to gain ground against a blaze of more than 153 square miles (396 square kilometers) that destroyed over 500 structures in Malibu and other Southern California communities. At least three deaths were reported.

AP