As far back as 1971/2, Soviet Air Defence radar spikes were quite visible on the C-141's APN 59 weather/mapping radar when passing up off the Kamchatka Peninsula en-route from Yokota AB in Japan to the West Coast on the NorthPac 1 route. In addition, one night in the wee hours between Johnston Island and Hickam, I became aware of similar spikes emanating from something on the sea below. To keep awake, I filled in one of the report forms in the route bag and handed it in at Operations after landing. By the next day, as we collected paperwork for return to Travis, that report had been upgraded to Secret with Codewords attached - so somebody seemed to think that there had been something of interest out there. All of that said, I don't ever recall seeing anything similar, anywhere around the globe, on the Ekco weather radars fitted in any of the three RAF Transport aircraft types I flew.