I use a few tools to figure out is the propagation is "On"
The first one I use is PSK reporter...For example, I will TX using 10 watts, and see my signal strength, across the world...From there I can deduce if my SSB will close the link to the desired DX station
Another tool I use is VOACAP...That is one need tool...Plug in your desired DX, put in your antenna, power, band and assumption of DX Station, and presto, you will know if you can make the DX
But the PSK reporter is the real deal, and in real time...You can't miss
Nothing worse than calling CQ for a Half hour, and no returns! But if you know the bands are "On" by using the above tools, you can have more confidence of success landing DX QSOs
Cheers
DE NN2X TOM