UN: Radioactive Plume Could Come to South California By Friday

The forecast explained that the plume will lose radioactive force as it travels and may not even be detectable by the time it reaches Southern California.

The projection, made by the Comprehensive Test Ban Treaty Organization in Vienna, is based on patterns of Pacific winds and gives no information about actual radiation levels. It is likely to change if the weather shifts over the next few days.

The Chernobyl disaster in 1986 also made its way to the West Coast in 10 days, but radiation levels were too low to register.

In the case that the plumes do make it ashore, the U.S. Environmental Protection Agency has said it will deploy additional electronic monitors to measure radiation levels in the air.

The monitors, which detect gamma radiation and radioactive particles, will be set up in "parts of the Western U.S. and U.S. territories," the agency said in a statement.