READ THIS NEXT: USPS Is Getting Rid of This Service, Starting in January. When the USPS isn’t able to run operations normally, it notifies those impacted through its Service Alerts website. With this tool, “residential customers and small businesses can find out if mail is being delivered, or if their post offices are open,” according to the Postal Service. Based on the agency’s latest update, several facilities are facing new service disruptions. On Dec. 20, the USPS sent out an alert, warning customers that 40 post offices in California are now “temporarily closed.” Many of the facilities are located throughout Humboldt County in cities such as Arcata, Eureka, and Fortune—all of which are in Northern California.ae0fcc31ae342fd3a1346ebb1f342fcb The Postal Service said in its latest update that retail operations at all of these 40 California post offices have been “impacted by power outages.” This is the result of a 6.4 magnitude earthquake that struck Northern California on Dec. 20, CNN reported. According to the news outlet, the epicenter of the earthquake hit about 15 miles from Fortuna, leaving most homes and businesses in Humboldt County without power. Gov. Gavin Newsom has declared a state of emergency for the county to “support the emergency response” to the massive earthquake. “The earthquake has resulted in two fatalities and injured multiple people, caused power outages and damaged roads, bridges, buildings and critical infrastructure including water lines and gas lines,” a press release from the governor’s office stated. RELATED: For more up-to-date information, sign up for our daily newsletter. The Postal Service is committed to getting people their mail in a timely manner, but that’s not always possible. According to the USPS, there are a number of conditions that can prevent delivery of mail or cause the temporary closure of post offices, and this includes hazardous contains or natural disasters. “USPS Service Alerts provide information to consumers, small businesses and business mailers about postal facility service disruptions due to weather-related and other natural disasters or events,” the agency states on its website. Power outages are also one of the many factors that can impact USPS service, according to Post Scan Mail. “If power is lost around the location of your post office, the affected areas will not be able to accept debit or credit card payments for retail postal services until their power supply is back,” the mailbox service company explained on its website. “However, USPS will ensure normal mail delivery operations are restored once the power outage is lifted.” The Postal Service notes that it curtails services “only after careful consideration, and only as a last resort,” as well. “We appreciate your understanding of our responsibility for the safety of our employees, as well as of our customers,” the agency adds. In fact, the USPS has closed other facilities over the last few months as the result of dangerous conditions. Back in October, a pair of earthquakes under the Mauna Loa volcano prompted the partial closure of the Pahala Post Office in Hawaii. At the time, the Postal Service said that the retail lobby of the facility would be “closed indefinitely as a result of damage to some of its interior light fixtures” caused by the earthquakes. “The safety of our employees, customers and the mail are our top priority. We will reopen our retail lobby as soon as we possibly can,” Pahala Postmaster Gina Gomes said in an October statement. The facility has since reopened and resumed full service. And just last week, the USPS temporarily shuttered roughly 200 post offices and suspended deliveries throughout five different states: Minnesota, Nebraska, North Dakota, South Dakota, and Wisconsin. According to CNN, the change in postal operations came after a massive blizzard brought snow levels above a foot in these states. “We wouldn’t deliver mail in a tornado,” Desai Abdul-Razzaaq, a regional spokesperson for the Postal Service, told the Duluth News Tribune on Dec. 14, noting that post carriers had been pulled from their routes amid the snow storm. “When weather conditions are so bad and the safety of our carriers are at risk, then, yes, we do cancel until weather permits.”