Me thinks I may have encountered such weather on flights made together out of that Sunshine Holiday Capital in the Shetlands as we flogged to and from the Ninian Field in its early days.
In the time of Decca finding home was more by Braille than by Science.
Memory serves me that VMC Minima was lower than IMC.....something about clear of cloud (which Fog ain't it being a surface weather phenomenon and all).
For sure you could not see over the nose of the Helicopter and see anything but gray....requiring you to look down past your elbow to see anything Green.
All by the book of course!