SAN FRANCISCO (CBS SF) — Vail Resorts announced Saturday they were shutting down operations at their ski areas around the country including Heavenly Valley, Kirkwood and Northstar in the Lake Tahoe area for at least a week because of the growing coronavirus outbreak.

Hours later, Alterra Mountain Company destinations announced it was also shutting down operations at its Squaw Valley Alpine Meadows, Mammoth Mountain, June Mountain and Big Bear Mountain resorts in California. Those resorts will be shut down indefinitely.

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“I sincerely apologize for the inconvenience this short notice will undoubtedly create,” Alterra CEO Rusty Gregory said. “We look forward to welcoming you back to the mountains as circumstances improve.”

Meanwhile, Vail Resorts said all 37 of their resorts would close Sunday and not reopen until at least March 22 while officials evaluate the impact of the virus outbreak.

Word of the closure came as the Tahoe area was bracing for a winter storm bringing as much as 4 feet of new snow to the ski runs.

“This has no doubt been an incredibly challenging time,” company CEO Rob Katz said in a statement released announcing his decision to shut down the resorts. “With 37 resorts spread across 15 states and three countries, we, like the rest of the world, have been closely tracking every new development related to coronavirus (COVID-19) and have been in constant contact with local health officials for guidance.”

“Without question, our top priority has been the health and wellbeing of our guests and employees and to no lesser extent the health and wellbeing of the communities where we operate. We know each decision we make has a broad impact far beyond our operations.”

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Resort officials said they would use the time while the resorts at closed to reassess their approach for the rest of the season.

“Our lodging and property management operations will remain open to service the guests we have on location or those with existing reservations, but we will not be taking new reservations for this upcoming week,” Katz said.

Officials said all employees, both seasonal and year-round, would be paid during the eight-day period without needing to use any vacation or sick time.

“This was not an easy decision to make, as we deeply considered the impact it will have on our guests, employees, and the people and businesses in our communities,” Katz said. “We understand this change may be confusing given our communications of operational changes over the past week, and as late as last night. Please know that this has been a fast-moving, constantly developing situation with new information from our communities coming to us by the day, if not by the hour, and we are trying to react as quickly as we can.”

“We sincerely apologize to guests who are currently at our resorts and those who were planning to come during this time.”

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Officials said refund information can be found on the company’s website.