Over the last couple of weeks I've been startled to hear (and work)
stations in Asia and the Pacific in broad daylight, between 9AM and 10AM
CST. I even managed to snag T88XC at 9:30AM on JT65 running 20 Watts into
a vertical.

How long has this been going on? I always considered 40 to be a late
night and early morning DX band, and don't usually check the band
much during the day.

--
Bert Hyman W0RSB St. Paul, MN

Well Bert, is has been my experience that during the day, the 40 meters is used most often in the East Coast by mobiles because it is the easiest to work.

One rule of thumb - when the VHF is booming, the HF usually sucks, other then the lower bands.

When the 10 / 12 / 15 meters is open, the VHF usually sucks!

With inversions in the atmosphere with all this goofy weather we have been having lately - it is possible to get 2 or sometimes even 3 e hops when working the gray line.

You just need to keep in mind where the gray line is at different times of the day.