it was really unsettling - we had good weather with 20C, no rain, not even cloudy, but visibility was well below 20km. Even mountains which were like 15-20km from my viewpoint, were barely visible. With normal visibility, from where I hiked, I should have easily seen mountains 50-80km away (and not just see them as a line on the horizon - during my past hikes I had been able to distinguish and name almost every single peak!)