SAN FRANCISCO (KPIX 5) — PG&E officials on Friday warned customers this weekend’s power shutoff could last 48 hours or even longer and is likely to impact 850,000 customers spanning 36 counties starting tomorrow.

“We are preparing for what is likely going to be a widespread safety shut off across our service territory to combat the risk of a catastrophic wildfire,” said PG&E Executive Sumeet Singh.

The historic wind event is expected to last until Monday. PG&E said they will decide Saturday at 8 a.m. after looking at the forecast who will in fact have their power shut off.

But PG&E officials said they’ve learned from this week’s outage after admitting they only shut off low voltage lines and not high voltage transmission lines prior to the Kincade Fire because winds weren’t strong enough.

“We have revisited and adjusted some of our standards and protocols to determining when we will de-energize a high voltage transmission line,” said PG&E Utility President and CEO Andy Vesey.

He said if power lines are in areas with higher winds than forecasted because of topograpghy — for example, ridges that act as wind tunnels — those lines will likely now be shut off.

A transmission line at one of PG&E’s towers failed just minutes before the Kincade Fire began Wednesday night. Last night, PG&E officials did not have an answer as to why it took crews ten hours to inspect the faulty line.

On Friday, however, Veyes answered the question when asked again.

“We dispatched qualified electrical workers to the site, they were there within 90 minutes, but at that time the fire was already on going and our people could not get to the structure,” he said.

While the outages may be widespread, so is the anger and frustration among customers.

PG&E officials confirmed some are having their power shut off when they don’t necessarily live in an area impacted by high fire danger or winds.

“One of the things that we’re committed to do as soon as we get through fire season and we can sit back is to really think about what additional sectionalizes we need to put in, how we might be able to reconfigure the system, so that areas that don’t typically see bad weather, but are somehow connected through the system will not be impacted,” Veyes said.