YOKOTA AIR BASE, Japan — A powerful thunderstorm ripped through Yokota on Saturday afternoon, dumping marble-sized hail, knocking out power in many buildings, uprooting trees and causing minor low-level flooding.

Other U.S. military bases on the Kanto Plain reportedly fared better. Camp Zama received some rainfall but no high winds, while Atsugi Naval Air Facility — where a major festival was under way Saturday — encountered no weather problems.

At Yokota, no major damage or injuries were reported. A base spokesman said security forces and civil engineering personnel were dispatched to unclog drains, restore power and clear roads littered with limbs, branches and leaves.

In downtown Tokyo — sweltering in high humidity and temperatures that spiked to 95 degrees Saturday — public address loudspeakers announced a severe weather alert as lightning flashed and thunder echoed off skyscrapers.

The storm struck Yokota with more ferocity than the 50 mph to 60 mph winds typhoons bring when they pass through the Tokyo area. Maximum wind speeds at the base were unavailable Saturday because the power failure affected data storage equipment, officials said.

People on base scrambled for cover as an outdoor bazaar at the Yujo Recreation Center had to be quickly dismantled and brought inside.

“Some CE people got recalled for cleanup duty,” said Capt. Warren Comer, a 374th Airlift Wing spokesman. “We got some strong winds. It was a sudden storm that came in fast and blew some things around. … I’m sure it disrupted a few picnics and the Yujo bazaar. They didn’t have much time to take everything inside. The hail was coming down hard.”

The storm hit Yokota just after lunchtime Saturday. The sky turned an odd orange-tinted glow, followed by heavy downpours, high winds, thunderous booms and lightning flashes.

At least one window was blown out in an older single-story office building that sits across from the Yokota Community Center.

Strong downbursts toppled a large tree near the Samurai Cafe, the base’s dining facility. It fell across Airlift Avenue in the heart of Yokota. Traffic was blocked briefly in both directions as heavy-lifting crews pulled it off the road.

In Yokota’s north housing area, a trampoline was flipped over a concrete wall and onto Airlift Avenue not far from the Terminal Gate. Five security forces members were needed to return it to the backyard of a garden apartment building.

A cluster of buildings, offices and warehouses on the base’s south side — including the Yokota Par 3 Golf Course, Auto Hobby Shop and Stars and Stripes bureau — remained without power until about 5:30 p.m. Saturday.