It has been a "bad hair day" on 10m today.
The first USA station to spot my 500mW beacon was at 1610z (very late) by WG2Z (5600km). This reminds me of the brief 6m F2 openings to the USA many years ago. To be honest, I was beginning to think that an opening to the USA would not happen at all today. In a few months we'll be on the look-out for multi-hop Es across the Atlantic in the Es season.
UPDATE 1808z: Only 2 USA stations have spotted my 500mW beacon today with K9AN (6505km) at 1754z. I suspect conditions are changing.
UPDATE 1940z: It now seems that the 1902z spot by K9AN of my 500mW 10m beacon was the last today by a station in the USA. Since then, just local UK spots.
UPDATE 2010z: Now going QRT on 10m. Still active on 160m WSPR where I have received 36 unique spots using my earth-electrode "antenna".