Washington ? Those vague domestic terrorism alerts from grim-faced federal officials haven’t worked well, experts say, so the terror warning system is about to get an overhaul.

Homeland Security Director Tom Ridge is expected to unveil a new terrorism alert system in the next few weeks. His office is floating a four-step system whose alarms would be, in descending order, “Critical, serious, alert and ready,” according to Peter Ward, interim chairman of the Partnership for Public Warning, a new nonprofit group in McLean, Va., promoting a better national alarm system.

The idea, said Homeland Security spokesman Gordon Johndroe, is “to have a system that is understandable.”

It would be employed for ” a cross-section of events and places,” including all kinds of terrorism and, possibly, for natural disasters as well.

Police and disaster experts deplore the current sequence of four vague terrorism warnings, in effect continually since Oct. 11. Police and disaster experts say they’re worthless.

“We use them as bad examples in class because they violate all of the guidance that we’ve come up with from disaster research,” said Mike Lindell, director of the Hazard Reduction and Recovery Center at Texas A&M University in College Station, Tex. “They don’t tell you what to do other than be vigilant. What’s that? We don’t know.”

An alert system that keeps people perpetually on edge “contributes to complacency … You can only be alert so much,” said North Carolina Emergency Management Director Eric Tolbert, president of an association of state disaster chiefs.

Now the question is how to devise warnings that work.

On Thursday the head of the National Oceanic and Atmospheric Administration will meet with Ridge’s staff to propose that the new warning system be broadcast over NOAA weather radios, said Don Wernly, chief of the agency’s warning system.

Next week, the nation’s state disaster chiefs will meet in Washington to discuss, among other things, a better terror warning system. Ward’s partnership wants to unify the varying disaster warning systems used for weather, volcanoes, nuclear power plant disasters, civilian terrorism and military preparedness.