Japan's Nuclear Fallout Maps: Photoshop Hoax or Not?

Nuclear Fallout Map Snopes
Claim: Map issued by Australian Radiation Services shows expected path of nuclear fallout across the western United States.


Winds at Japan Power Plants Should Send Radiation out to Sea
Calculated time for radioactive particles to cross the Pacific from the power plants in Japan to big West Coast cities if the particles take a direct path and move at a speed of 20 mph:

Cities Est. Distance (miles) Est. Time to Cross Pacific (days)
Anchorage 3,457 7
Honolulu 3,847 8
Seattle 4,792 10
Los Angeles 5,477 11

Are We In Danger of Radioactive Exposure from the Japanese Nuclear Leaks? ZeroHedge
The worst case scenario is that the fuel rods fuse together, the temperatures get so hot that they melt together in a radioactive molten mass that bursts through the containment mechanisms and is exposed to the outside. So they spew radioactivity in the ground, into the air, into the water. Some of the radioactivity could carry in the atmosphere to the West Coast of the United States.

U.S. West Coast in Path of Fallout Prison Planet
“If There Were a Reactor Meltdown or Major Leak at Fukushima, the Radioactive Cloud Would Likely be Blown Out … Towards the US West Coast”

The top two fallout maps have been widley circulated thoughout the web and this was before the recent reactor explosions in Japan. Is this an example of myth preceding reality or just dark humor?