Extreme weather across the United States, from huge floods to deadly tornadoes, has led to $32 billion in economic losses so far this year, the director of the National Weather Service said Thursday.

"It has been a costly year for extreme weather," Jack Hayes told reporters on a teleconference, referring to the thousands of homes and millions of acres of farmland lost.

"The steady rise in extreme weather and the nation's growing vulnerability to these events has moved us from concern to action."

The country has experienced severe weather throughout 2011, from the record spring rainfall that overwhelmed rivers already swollen from the melting of heavy winter snows, to the searing summer heat now affecting many states.

Drought in the southern part of the country is the worst in decades, with dry conditions sparking massive wildfires. Tornadoes have killed more than 540 people in 2011 -- the highest toll in more than 60 years.