Its just the way the winds seem to work. A change of 5 degrees can make it swap from one side of a ridge to the other so you can go from having to shove the nose down with the power off and still be climbing at Vne to 30 seconds later to max chat at the stall going downwards like a brick parrot.
If the wind increases by 5 knts it gets bounced off high and if it drops by 5 knts you get a more linear flow over the hill and no rotar. In the middle you get sheds loads of turbulence.
You are quite right a radio doesn't help with a CFIT if thats what it was, which we have no way of knowing yet. Scottish pilots tend not to
about with clouds unless above MSA they invariably have hard centers.