More than an inch of drenching rain, sometimes accompanied by thunder and lightning, poured down on Washington yesterday in intense bursts that overwhelmed drainage systems and flooded several major streets and intersections.

In addition, hail measuring one-half inch in diameter was reported in Alexandria, and storm-related power failures affected 10,000 or more homes throughout the area, authorities said.

At times during the day and evening, most area roads and streets shimmered under sheets of rainwater, and in one extreme case, depths of three feet were reported on a west-bound section of the Capital Beltway in Springfield.

A northbound strip of the Anacostia Freeway in Washington was closed for a time between Minnesota and Keilworth avenues and part of Nannie Helen Burroughs Avenue in Northeast was reported still closed late last night. In Rock Creek Park, the U.S. Park Police said they expected Beach Drive between Broad Branch and Joyce roads to remain closed under high water until early today.

Flooded intersections, the result of clogged or overtaxed storm drains, were reported at such spots in Northeast as Bladensburg Road and V Street, 15th and H streets and 18th Street and Benning Road.

By late last night, the National Weather Service had recorded 1.34 inches of rain at National Airport and 1.21 inches at Dulles Airport. Although the rain was heavy, winds were light, particulary for a day of sporadic thunderstorms. Winds at Dulles never exceeded 12 or 13 miles an hour.

Weather service forcaster John Forsing attributed the thunderstorms, with their billowing black clouds, to a weak cold front that passed through the area yesterday, wringing moisture from the warm air that had lodged here for the past few days.

The relatively feeble force of the winds failed to drive all the moist air from the area. Forsing said, and clouds are expected to linger through the early part of today. Fair weather is expected tonight and tomorrow.