Polar winter echoes

Following several periods of unsettled geomagnetic conditions, quite frequent and strong Polar Mesospheric Winter Echoes (PMWE) have been occurring at high latitudes.

Today, PMWE were again strong - as strong as we might see in the summer. Sometimes, the formation of PMWE and Es happens at the same time, other times not.  The forcing mechanisms for PMWE and Es are often the same, though they are regarded by some - by no means a consensus - as separate phenomena.

The kind of PMWE return strength that we expect in summer, not winter.

 

Of course, the apparent occurrence of Es depends on where it forms, and its alignment with various places. Today, it seems any Es that may have occurred is nowhere near Europe, as 10m is only weakly open from where I am, and there seems to be no opening elsewhere. 12m, on the other hand, is very active.