Happen to notice at work today that I had a spike show up on my detector, figured it was a PC lag doubling my count and probably was, but then got home and see there were 2 alerts from stations nearby and just checked them and quite a few of them showed some decent spikes all around me, and at a hundred miles out from my location. We have had some rains here, but mostly drizzle, no downpours and washouts, just plain drizzle so I don't think its a Radon affect unless someone thinks it is.

Can you please post a link to your stations graph?

Netc's Animation feature shows a clear line of Radcon 3, 4 and 5 alerts along the eastern seaboard earlier today. I can't seem to get doppler maps from more than a few hours ago (the alerts stopped by 5:00 pm), but it appear the rainy weather is highly correlated based on http://earth.nullschool.net/.

The EPA data is collected at 6 hours groups because the EPA will not post the data every hour, so Netc's animation map must be 6 hours delayed. The static map is always up to date with the data from all stations.