As Monday's devastating touch down in Moore shows, a slow start of the season says nothing about how it how it could eventually shape up.
"It was quiet in February through April; that doesn't tell us anything that will happen in May," Brooks said.
As Moore residents frantically searched the wreckage of schools and homes destroyed by Monday's strike, communities elsewhere in Oklahoma and the region were bracing for the possibility of new funnel clouds or huge hail stones.
Hours before the Moore strike, National Weather Service meteorologist Peter Snyder predicted that twisters could touch down in the region and other areas to the east.
"There's a good environment for super cell development and it could develop a squall line that produces 70 mph wind and clusters of thunderstorms," Snyder said. "It's a similar situation (as Sunday) but it will affect points east today."
The deadly tornado strikes began Wednesday, when a twister outbreak in North Texas killed six people and injured dozens of others, many in the community of Granbury. A massive storm system that moved through the Plains and Midwest on Sunday produced tornadoes in Kansas and Iowa, but it was Oklahoma that bore the brunt of the destruction, with at least 39 injured throughout the state and two deaths from a tornado strike near Shawnee, 30 miles east of Moore.
Associated Press Science Writer Seth Borenstein in Washington, D.C., contributed to this report.