UPDATE 1-Oncor says Texas power outages fall to 85,000

(Updates outage figure)

NEW YORK, June 12 (Reuters) - Oncor expects to restore service by the end of the weekend to the remaining 85,000 homes and businesses in the Dallas/Fort Worth area still without power, a spokeswoman for Texas' biggest power distribution and transmission company said Friday.

She said this was one of the top three worst storms in the company's history, knocking power out to an estimated 500,000 customers over a two-day period as a series of storms moved across the northern half of the state.

At the peak, about 260,000 customers were without service.

The company's worst storms occurred in June 2004 when 1.4 million customers lost power and May 2007 when more than 620,000 were left in the dark.

Oncor has already restored power to some 415,000 customers since the storm began on June 10. As Oncor crews and contractors restored power to affected customers, the company said other homes and businesses lost power from the subsequent storm waves.

The weather in the Dallas-Fort Worth area is currently sunny and humid, but later Friday the mercury will soar to the mid 90s and damaging thunderstorms are forecast to return, according to AccuWeather.com.

In a release, the company said the national Lightning Detection Network reported about 45,000 lightning strikes occurred in the Dallas/Fort Worth area during the storm waves.

Oncor transmits and delivers power to about 3 million homes and businesses in Texas.

Energy Future Holdings owns three business units - TXU Energy, a competitive electricity retailer; Luminant, a competitive power generation business; and Oncor, a regulated power distribution and transmission business. (Reporting by Scott DiSavino and Eileen O'Grady; Editing by John Picinich)