Updated

About 20,000 customers are without electricity in the Denver area amid a powerful wind storm.

Xcel Energy says the blackouts affected about 50,000 customers in Denver, Fort Collins and Greeley starting at 10 p.m. Tuesday. Crews restored service to most by midday Wednesday.

The company hoped to have everyone online Wednesday afternoon but later said it might be evening.

The National Weather Service expects sustained winds of 25 to 40 mph with gusts of up to 60 mph possible across eastern Colorado Wednesday.

By early afternoon, 40-mph gusts had been reported in a handful of northern and northeastern Colorado communities.

The wind and low humidity prompted forecasters to issue a red flag warning for eastern and southeastern Colorado, meaning the danger of fire is very high to extreme.