https://www.sfgate.com/sfhistory/article/the-skylab-race-to-san-francisco-18074888.php
After its launch in 1973, Skylab was a successful observatory and laboratory that saw three separate crews climb aboard to conduct experiments over 24 weeks. But by 1979, with the country’s interest in space already waning, diminished budgets and a delay in construction of a shuttle needed to refuel it, the only solely American-owned space station in history was left derelict, and would eventually fall back to Earth.
While the agency insisted that injuries were very unlikely, it did add that if citizens of any country heard that the space station was falling nearby, they should maybe hide out in the lowest floors of their homes.
Skylab was the size of a three-story house and was expected to break into about 500 pieces upon reentry anywhere in a wide band around the Earth that covered 90% of the population. In late June, NASA said that Skylab would hit around July 10 to 14, but that NASA would only have a two-hour period of notice to pinpoint where it would land after the space wreck pierced the atmosphere.