I remember those early games of mine!! Blimey I must've been fit, running about like a March hare haha
Totally your call then mate, they're difficult enough without mother nature chipping in! Taking into account you'll probably be running a shallow diagonal*, the formula still works for you, if you're having any difficulty identifying players anywhere on the FOP (in case of mischief in the fog) you might be wiser not starting/not continuing. If it's expected to lift, perhaps think about just suspending play? see if it'll clear, dependant on time or other games perhaps following of course
You may well have 30-40 meters visibility from wherever you are at any given moment, but keep asking yourself 'can I now see the whole FOP?' I don't think I'd be comfortable trying to control players/officers I can't actually see Micky.
Even money at the bookies (not that I endorce betting) that at least one player'll shout 'Even the ref says he can't see!'
*Working on my own, no linesmen, I found it a good idea to patrol the area within the width of the penalty area when possible, and only as far as the front edge of each at both ends, so limiting runs I made to the touchline and goal lines to 'absolutely essential I'm here' only, just to save on my energy/stamina. You do drift as the ball travels one way or another, most throw/gk/corner decisions you'll pretty much be in a 'credible' position anyway, as you run straight rather than off to one side each end. The line where you'd expect your linesman to be normally you can still drift towards, it'll mean you 'looking' at offsides from both sides of the FOP if you get it off to an art, as long as the players are all in your view.
You can't guarantee being dead right position wise for offside, but it'll demonstrate to the players that you're very much making an effort mate. Years ago we were taught to run left and right wings as linesmen, so a lot of us practised running the 'wrong' diagonal in the middle. Having done loads of games on my own in my early days, it worked to my advantage. I don't think they encourage swapping diagonals any more, but in the first minute of the 2nd half a full back would say 'What you doing over here Ref?' I'd wink and say 'Keeping a closer eye on you', they always laughed......luckily!
