About 20 seconds before the magnitude 7.1 earthquake struck near Mexico City on Tuesday, sirens went off around the area.

They were part of the country's earthquake early warning system, a system that alerts the public seconds, and in some cases minutes, before an earthquake strikes.

It's also technology scientists are working to bring to the Pacific Northwest.

It's called ShakeAlert.

"It could save your life if you were in a precarious situation," said Mouse Reusch, regional ShakeAlert coordinator.

Here's how ShakeAlert works:

The moment the fault breaks, offshore and on-land sensors pick up the quakes fast moving P-waves and immediately issue an alert.

That alert will lets us know how much time we have before the slower and much more damaging surface waves arrive.

In the event of a major Cascadia Subduction Zone quake, it could give people in Portland as much as three minutes of warning.

"Would we be better off and be able to recover faster and have fewer fatalities and fewer casualties? Yes," said Reusch. "I think ShakeAlert is really very important for the West Coast."

Coordinators are hoping to roll out ShakeAlert to some public institutions by the end of next year, but admit it could take several years before it's available to the general public.

President Trump's initial budget cut all federal funding for earthquake early warning. But recently, congressional committees restored that funding.

The system would cost about $16 million a year to operate. Scientists have about $10 million of that covered, but still need another $6 million.