Rain blew the blues away Sunday, but Washington had its Brass Monkey Blues Festival anyway as 1,500 high-spirited and vociferous blues lovers showed up for the rain date last night and boogied in their seats at Carter Barron.

With Nap ("Don't Forget the Blues") Turner as the emcee, the nearly five-hour blast opened with traditional acoustic sounds and ended with high-energy updated electric blues.

Alone on the stage but in need of no company, Rory Block recreated with her voice the cadences, inflections and earthy realism of the classic country blues, while her guitar punched out walking basses and whined bottleneck slides.

"Harmonica" Phil Wiggins and guitarist "Bowling Green" John Cephus were a tight team, working so closely that their instruments often seemed played by one individual. Their unison vocal on "Up Down" had the house rocking.

The earth shook when Lonnie Brooks came on with his five-piece band for a set of pile-driver beat, latter-day Chicago blues. Brooks once or twice played his guitar behind his back and even applied teeth to its strings for several electrifying bars.

Luther "Guitar Jr." Johnson, a player of subtlety and understatement, used electronics to convey nuances of emotion in a satisfying set. He was given excellent laid-back support by his rhythm section. Ron Levy's electric organ offered especially sympathetic foundation for Johnson, and his solos were substantive.

Well deserving of their top billing, those area favorites, the Nighthawks, came on as the final act with a blend of wailing harmonica and hornlike guitar lines over a driving ground beat. They are a quartet, but their riff-filled arrangements lend to them the impact of a group twice that size.