WASHINGTON (CBSDC/AP) — District of Columbia Mayor Vincent Gray has asked the White House for a federal disaster declaration in anticipation of major damage from Hurricane Sandy.

District officials say they are expecting between 5 and 10 inches of rain, and they’re concerned about flooding in parts of the city. Gray has already declared a local state of emergency.

A decision to close D.C. schools on Monday has already been made.

Chris Geldart, director of the D.C. Homeland Security and Emergency Management Agency, says people with trees around their homes are advised to stay on the lower levels. He says the storm is unusual because sustained winds of 35-45 miles per hour are expected to last for more than 24 hours, starting around noon Monday.

Pepco regional president Thomas Graham says the utility has requested 3,700 out-of-state workers, the most in its history.

The president has already signed an emergency declaration for Maryland.

RELATED

Hurricane Resources

(TM and Copyright 2012 CBS Radio Inc. and its relevant subsidiaries. CBS RADIO and EYE Logo TM and Copyright 2012 CBS Broadcasting Inc. Used under license. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed. The Associated Press contributed to this report.)