LOS ANGELES — Less than two weeks after it was slammed for cutting off power to hundreds of thousands of customers to prevent wildfires, California's biggest utility said Monday it will likely have to do it again this week.

Pacific Gas & Electric Corp., or PG&E, said at a hastily arranged late afternoon news conference that it was calling, emailing and texting more than 200,000 customers in 15 Northern California counties to alert them that their power could be shut off for as long as 48 hours, starting Wednesday.

A power "customer" can be a single residence or a large business; the standard conversion utilities use assesses 2½ people per customer, meaning as many as a half-million people could be affected Wednesday. Most of the impact will be felt in the Sierra Foothills and the northern part of the San Francisco Bay area, the utility said.

PG&E said high winds and dry conditions would lead to a critical risk of wildfires sparked by faulty electric lines. Those same conditions plunged as many as 2 million people into darkness two weeks ago in rolling blackouts, which PG&E called a public safety power shutoff.

Californians from Gov. Gavin Newsom on down slammed PG&E for that blackout, especially as it, like other utilities, has a policy of not reimbursing customers for lost business, housing alternatives or spoiled food and medicines.

To make matters worse, heavy user volume crashed PG&E's website for long periods, keeping customers from getting critical blackout and safety updates. Newsom said he was "outraged" by PG&E's performance, while state regulators called it "unacceptable."

PG&E said it was setting up a separate dedicated website to handle the extra load this time.

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Blackouts are "certainly not a tool we like to use," PG&E Chief Executive Bill Johnson said Monday. "It runs against the grain of why most of us got in the business."

But PG&E said the blackouts could be necessary because strong, dry offshore wind gusts that could exceed 55 mph were expected Wednesday and Thursday. In a notice to investors Monday, the utility said it found more than 100 "serious hazards" on its transmission lines from wind gusts during the shutdown two weeks ago.

PG&E is rushing to upgrade its equipment after years of neglect, which it has acknowledged contributed to deadly wildfires in the last few years. Johnson told state regulators last week that power shutoffs could be needed for as long as another decade.

PG&E's energy unit declared the largest utility bankruptcy in U.S. history in January as it faced massive liabilities from its role in several highly destructive fires that burned hundreds of thousands of acres of Northern California in 2017 and 2018.

More than 80 people were killed last year in one of the blazes, which was dubbed the Camp Fire. The company could be on the hook for up to $18 billion in financial damages at a scheduled trial over its responsibility in the Camp Fire and other devastating wildfires going back to 2017.