2 Million People Are At 'High' Risk For Catastrophic Tornadoes In Parts Of Oklahoma And Texas

(CNN) -- For the first time in two years, forecasters have issued their most dire warning for the risk of catastrophic tornadoes. The target: parts of the Texas Panhandle and Oklahoma, which is also marking the sixth anniversary of a tornado that pulverized the city of Moore, killing 24 people.

Over 2 million people are in harm's way, with the National Weather Service's Storm Prediction Center issuing a threat level 5 out of 5 for violent tornadoes Monday.

"This event should result in a significant threat to life and property," the Storm Prediction Center said.

Forecasters also said conditions are favorable "for long-track strong tornadoes and possibly violent tornadoes."

To put things in perspective, violent tornadoes make up only 0.5% of all tornadoes but account for about half of all tornado deaths, CNN meteorologist Brandon Miller said.

But it's not just tornadoes expected to wreak havoc Monday.

More than 50 million people are at risk of other severe weather, including fierce winds, large hail and flash flooding, Miller said.

On top of that, "there is also a high risk for flash flooding from parts of Oklahoma and Kansas, where rainfall totals of 3-6" will fall on already saturated ground," CNN meteorologist Dave Hennen said.

The risk is so high, schools are closed in some of the hardiest, most storm-weathered cities: Oklahoma City and Tulsa.

What makes this rash of storms especially dangerous

The Storm Prediction Center issued a rare "particularly dangerous situation" tornado watch for much of western and central Oklahoma, including the entire Oklahoma City metro area, until 10 p.m. Central Time.

The designation means that "an outbreak of tornadoes, including the risk of intense and long-track tornadoes" is expected across the watch area.

The chances of tornadoes -- including strong ones -- severe wind in excess of 75 mph, and hail larger than two inches are all greater than 95%.

Several airlines canceled afternoon and evening flights at Will Rogers World Airport in Oklahoma City to "prevent extended delays in other cities or to avoid having aircraft damaged due to high winds or hail," the airport said.

"Tornadoes could occur well after dark, making this situation potentially even more deadly," Hennen said.

The National Weather Service office in Norman, Oklahoma, gave a stern warning to residents.

"Do not let your guard down on Monday night," the office said. "It looks like severe storms and flooding will be a big problem overnight ... into Tuesday morning."

Air Force base sends aircraft elsewhere

Tinker Air Force Base, about 8 miles southeast of Oklahoma City, is evacuating some aircraft ahead of the storm.

The number of aircraft being moved off base wasn't immediately known, a spokesman said.

As for personnel on base, all facilities have "shelter in place" areas where people can hunker down.

52 tornadoes in 3 days

States such as Louisiana, Oklahoma and Texas are still reeling from weekend tornadoes and storms.

In the past three days, 52 tornadoes were reported across seven states, CNN Meteorologist Michael Guy said.

In Ville Platte, Louisiana, a possible tornado damaged more than 50 homes and businesses, CNN affiliate WBRZ reported.

Further west, the storm wiped out roofs, barns and trees in DeRidder, CNN affiliate KPLC reported.

"We woke up to the sound of glass breaking, and went in and saw the window in the kitchen was broken," resident Dorine Bearden told KPLC.

"Before, I had always told my husband it looked like we lived in a park," she said. "And when I looked out there, that park was gone. It was heartbreaking."

Baseball-sized hail could be on the way

Destructive hail and brutal winds are also possible through Tuesday.

Oklahoma City and Texas cities such as Lubbock, Amarillo and Abilene could get pounded with baseball-sized hail and hurricane-force winds, the National Weather Service said.

After a brief break, the risk of severe thunderstorms will increase again, the National Weather Service's Fort Worth office said. It urged residents to have a "safe plan in place" for Tuesday.

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