tianli wrote:

But looking at all the propagation conditions I can find, ie.
mag storms (none, in fact unusually quiet) and Xrays (none, quiet),
nothing changed from eg. yesterday to today.

So what indicator is there that I'm not seeing?


It is all quite elementary really :-P

MW/BCB Propagation Primer
http://66.175.38.157/kn4lf8.htm

Propagation Outlook:

...the low bands of 160, 120, 90 and 80 meters saw the best
propagation
conditions since September 2004. Why? Because all of the general
guide lines
as spelled out by me further down in this outlook were met.

http://www.kn4lf.com/kn4lf6.htm