During a hurricane, storm surge is one of the greatest threats to life and land, yet many people don't understand the dire warnings from forecasters to get out of its way.

MIAMI (AP) - During a hurricane, storm surge is one of the greatest threats to life and land, yet many people don't understand the dire warnings from forecasters to get out of its way.

This season, forecasters hope to offer easy-to-understand, color-coded maps and change the way they talk to the public.

Simply put, storm surge is the abnormal rise of sea water. Predicting it is far more complicated, and so is explaining it. Forecasters at the National Hurricane Center in Miami discovered that again during a review of Superstorm Sandy.

Forecasts during Sandy were exceptionally accurate, but often confusing. Perhaps because so many things contribute to storm surge: intensity, pressure, forward speed, size, where it makes landfall and other factors.

Wind, humidity and rainfall combined precisely to create the massive killer tornado in Moore, Okla. And when they did, the awesome amount of energy released over that city dwarfed the power of the atomic bomb that leveled Hiroshima.

WASHINGTON (AP) - Wind, humidity and rainfall combined precisely to create the massive killer tornado in Moore, Okla. And when they did, the awesome amount of energy released over that city dwarfed the power of the atomic bomb that leveled Hiroshima.

Meteorologists contacted by The Associated Press used real time measurements to calculate the energy released during the storm's life span of almost an hour. Their estimates ranged from 8 times to more than 600 times the power of the Hiroshima bomb.

Scientists know the key ingredients that go into a devastating tornado. But they are struggling to figure out why they develop in some big storms and not others. They also are still trying to determine what effects, if any, global warming has on tornadoes.

Pounding rain soaked tornado-ravaged Moore, Oklahoma, on Thursday morning, and winds sent pieces of debris flying, hindering recovery efforts three days after the devastating tornado.

(CNN) -- Pounding rain soaked tornado-ravaged Moore, Oklahoma, on Thursday morning, and winds sent pieces of debris flying, hindering recovery efforts three days after the devastating tornado.

In addition to the 24 people killed in Monday's massive twister, two people died elsewhere in the state in storms Sunday, the Oklahoma Department of Emergency Management said.

In all, 377 people have been treated for injuries as a result of this week's storms, the department said.

Of the 24 people killed Monday, 10 were children -- including two infants, the state medical examiner's office said.

As water gushed through the streets Thursday, the National Weather Service issued a flash flood warning for the Oklahoma City area, including Moore, and a severe thunderstorm warning.

Strong storms in southwestern Oklahoma City "are making a (southeast) turn toward Moore," the National Weather Service tweeted at 10:30 a.m. "Small hail, gusty winds, lightning and flooding main threats!"

But shortly after, the service said storms were moving out of the metropolitan Oklahoma City area. "Next chance of storms is late tonight," the weather service tweeted.

Predictions of heavy wind gusts also brought with them the possibility, though slight, of an isolated twister in the area.

A group of people who rode out Monday's ferocious tornado in a bank vault huddled together under a tarp early Thursday near a CNN crew.

More thunderstorms could be ahead for the region through Memorial Day weekend.

Officials estimate that 12,000 homes were damaged or destroyed by the EF5 tornado.

On Wednesday, a command center set up to help people with insurance processed 4,000 claims, Oklahoma Insurance Commissioner John Doak said Thursday.

"We have it down to a science here," he said.

Some people may choose to move to another neighborhood, but most are indicating they want to rebuild in Moore, Doak said.

The two elementary schools destroyed will be rebuilt, the incoming superintendent of Moore public schools said Thursday.

"That's the beginning of the healing process," Robert Romines said.

The schools did not have storm shelters. At one, Plaza Towers Elementary, seven children died.

Six were 9-year-olds who died from asphyxia, or suffocation; one was an 8-year-old killed by blunt force trauma, the state medical examiner's office said.

Romines said he supports the effort to add storm shelters during the rebuilding. He called for funding from the Federal Emergency Management Agency to cover it.

Other schools that were rebuilt after a 1999 tornado have such shelters, he said. But numerous other schools don't. "As funds become available, we will look at that," Romines said, adding that money "is an obstacle."

The school year was set to end Thursday.

High school commencement ceremonies will take place Saturday in downtown Oklahoma City, Romines said. The community will "do the best we can and make sure that our students are all taken care of."

CNN's Sean Morris, Judson Jones, Vivian Kuo, Jennifer Delgado and John Berman contributed to this report.

Federal forecasters are predicting yet another busy hurricane season.

COLLEGE PARK, Md. (AP) - Federal forecasters are predicting yet another busy hurricane season.

Thursday's outlook calls for 13 to 20 named storms, 7 to 11 that strengthen into hurricanes and 3 to 6 that become major hurricanes.

The prediction by the National Oceanic and Atmospheric Administration is more than what's considered an average Atlantic season.

Last year was the third-busiest on record with 19 named storms. Ten became hurricanes and were two major storms, with winds over 111 mph.

That included Sandy, which caused $50 billion in damage even though it lost hurricane status when it made landfall in New Jersey.

The last time a major hurricane made landfall in the United States was Wilma in 2005. The seven year U.S. landfall drought is the longest on record.

The six-month season starts June 1.

Tornado sirens accidentally sounded Wednesday night in Crawford County.

Tornado sirens accidentally sounded Wednesday night in Crawford County.

During Wednesday night’s storms, the sirens were activated across the county just before 9 p.m.

As you might imagine, the alert startled some that severe weather was imminent but according to Emergency Manager Jake Watson, their system activated due to a technical issue and they're investigating why it happened.