PASADENA, Calif. (AP) _ A miles-long sidewalk slumber party ushered in today's Rose Parade, the annual New Year's Day procession of flowery floats and marching bands.

An estimated 500,000 people were encamped along Orange Grove and Colorado boulevards as the parade got under way this morning with a worldwide television audience of up to 365 million anticipated, organizers said.

Thousands of people had staked out prime curbside locations hours before the parade. Sunny skies prevailed after a New Year's Eve rainstorm _ it was 40 degrees beneath the palms at dawn with afternoon highs expected to peak in the low 70s.

The grand marshal was Roy E. Disney, newphew of the late Walt Disney.

Claudia Borrelli traveled from Hales Corners, Wis., where it was 32 degrees and cloudy this morning, to see the parade and the afternoon Stanford-Wisconsin college football battle in the Rose Bowl.

``We brought the weather with us because our guys are used to playing in the cold, none of this hot California stuff,'' Borelli said.

Sidewalks were jammed with sleeping bags, beach chairs and coolers, and the sleepy all-nighters who partied away 1999 were jarred alert by a flyover of a B-2 Stealth bomber. The crowd roared with approval.

There were 54 floats delivering the ``Celebration 2000: Visions of the Future'' theme in a display of technology and entertainment for the 21st century.

There was also a dose of old-fashioned tradition.

A Missouri couple _ Neil Neumeyer and Leslie Ogle of Kansas City _ exchanged wedding vows before climbing onto Florists' Transworld Delivery's ``Promises for Tomorrow'' float, which won the directors' trophy for artistic design and floral presentation.

Brimming with tulips, narcissus, hyacinths, lilies and roses, it depicted an elegant chapel garden and cascading floral arrangements along a fountain-lined aisle stairway.