TLDR couple real world ceilings to the IF visibility at airports in a 1:19 ratio.
Most people who’ve used IF for a long time have probably realized that IFR conditions are much more rare than they are irl. For example, this is what North America currently looks like (red → IFR, pink → low IFR):
Now if you load into almost any of these airports in IF you’ll find that it’s a perfectly clear day.
My understanding is that IF bases its airport weather purely off the real visibility, not the ceiling. And that’s makes perfect sense- after all we don’t have thick stratus layers yet. The issue is that it’s very common to have real airports reporting IFR ceilings but 10sm visibility.
For example look at KELK, it’s currently IFR since it’s 600ft overcast. However, the visibility is 10sm. This is pretty common in the real world.
If you go to KELK in IF it’s completely clear because the weather is only based off visibility. This is why IFR conditions are so rare in IF. If you think about the locations where IF does have IFR regularly (VIDP, KSFO, etc) you’ll see that these are locations where it’s a visibility issue (haze, fog), not a ceiling issue. However, IFR conditions due to ceilings are much more common irl which is why we’re missing out on so much good IFR flying in IF!
I believe there is a solution which doesn’t require any performance changes or cloud rendering: couple real world ceilings to IF visibility
To be clear I don’t believe this should be a 1:1 coupling. I.e 600ft overcast irl shouldn’t correspond to 600ft visibility in IF. We can do some quick maths to determine the appropriate ratio:
So we can see that 1:19 means you’d see the runway at the same time as a pilot flying the approach irl. Therefore, if we had a 600ft overcast we’d see the runway at 11400ft or just over 2 miles away. Again, just about where you’d get visual contact on the real approach.
I think this would be relatively easy to implement since the metars in IF do report the ceilings. They just don’t use the ceilings. In other words, all the necessary information is there, the visibility just needs to be adjusted accordingly.