Over the last few days I have been copying a lot of stations on 40m and 30m that I don't think I should be able to hear. Many of them are very strong. The distances involved are between roughly 60 and 300 statute miles, well within the "skip zone." Distribution within that range appears to be rather uniform. Stations at 100 miles appear to do as well as those at 200 miles. When I see stations coming in from such distances, I check the ionograms closest to me. None of them have (yet) shown foF2 support for NVIS anywhere near 40m or 30m, and none of them show foE support, either. These frequencies are far too high for ground wave over the distances seen. So I can't think of any propagation modes that can explain this. I have written to a few of the stronger stations to inquire about transmit antennas they are using, and almost universally, they are using antennas you would expect with NVIS -- low dipoles. One particularly strong station, at about 150 miles, was using a 40m antenna at 66', which is a little high for solid NVIS coverage on that band. If this was just one or two stations for an hour on one day, I'd chalk it up to "sporadic something-or-other" and move on. But this has been going on for days, for most of the day, and I suspect if I watch it for a while, it will continue. An interesting side-note -- I'm not seeing this on 20m. When I look at the map of the stations I have heard on 20m (so far), there's a very satisfying "skip zone" hole around my location. The unexplained propagation seems to be specific to 30m and 40m. Any idea how these signals are getting to me? When I look at all my texts on propagation, they tell me nothing that could explain this.