This map shows the estimated position of the nuclear radiation plume drifting towards the US at 2 am on March 22nd. Position is conditional upon wind and weather variations.
Now have an update on this map at this link.
This forecast comes by way of the Comprehensive Nuclear Test Ban Treaty Organization The Organization provides a confusing rider to the information thus-
“The forecast does not show actual levels of radiation, but it does allow the organization to estimate when different monitoring stations, marked with small dots, might be able to detect extremely low levels of radiation.”
They also specify that health and nuclear experts emphasize that any plume will be diluted as it travels and, at worst, would have extremely minor health consequences in the United States.