Workers begin to clear a downed tree in a yard along East West Highway Thursday morning Credit: Andrew Metcalf

Updated – Friday, 9:50 a.m. – High-speed hitting Montgomery County are expected to continue throughout the day Friday and throughout the weekend, according to the National Weather Service.

Already, the local power utility Pepco has reported about 15,000 customers in Montgomery County were without power as of 9:30 a.m. Friday. The winds have blown over trees, which have crashed into power lines and homes. In one instance, a tree fell on the home of a 100-year-old woman in Kensington, injuring her.

Read more – High Winds Result in Damages, Crashes and Fires in Montgomery County

Original story – 3 p.m., Thursday – Weather service meteorologist Dan Hofmann said Thursday afternoon the winds will be widespread throughout the Washington, D.C., region and are expected to significantly impact Montgomery County.

“It’s shaping up to be a pretty rare high-wind event,” Hofmann said.

He said wind gusts will increase to around 40 mph to 50 mph after midnight and then increase to around 60 mph to 70 mph during midday Friday. Sustained wind speeds will remain relatively constant between 25 mph to 40 mph throughout the day. Some rain showers are expected before the high-speed winds hit and a high near 46 degrees is predicted for Friday.

A radar image captured at 3 p.m. Thursday afternoon showing the approaching storm. Via National Weather Service

Gusts ranging from 30 mph to 40 mph are expected throughout the weekend, according to Hofmann.

“The storm will drift away, but it’s not going to move all that much,” Hofmann said. “The 60 to 70 mph wind gusts are relatively commonplace in intense summer storms, but that’s normally for a short period of time.”

He said it’s rare for high-speed gusts to continue over three days. The weather service is warning people to expect widespread power outages and prepare for losing electricity. Hofmann also said high-profile vehicles such as large trucks or vans should use extreme caution when traveling Friday, especially on overpasses where there may be dangerous crosswinds.

“If you don’t have to travel tomorrow, I would suggest you don’t, especially if you drive a high-profile vehicle,” Hofmann said.

The Capital Weather Gang predicts the winds will not be as strong as the Derecho that brought down power lines in the region in 2012, but the winds will be significant and last for an extended period of time:

Pepco spokesman Marcus Beal said Thursday the local electric utility is preparing to respond to power outages. He said wind gusts, which could send trees or limbs into contact with power lines, create the primary threat for outages.

The utility is planning to deploy its full complement of 150 internal Pepco linemen as well as 250 overhead line contractors and 180 tree crew personnel to respond to incidents as the storm unfolds.

He noted the utility has trimmed trees near lines, installed stronger power lines and inspected existing infrastructure over the past five years to prevent outages.

“We’ve done a lot to harden the system,” Beal said. “We want to try to prevent or minimize those outages.”

Hofmann said trees in the region are still bare, so there are no leaves to act as sails, which can put stress on trees and their limbs.

The Maryland State Highway Administration warned Thursday that recent rain has saturated the ground, which makes trees more susceptible to toppling over. It advised motorists to check wind warnings on its website before traveling.