You are just going to have to do a test on some scrap wood and see how it looks..
That is always a good idea, though it seems I'll have to wait till monday annyhow since now it's raining, and tommorow seems to have pretty high chances of rain too.
Did a bit more googling with better succes, if the results are anything to go by, between 40 and 50 is ideal and up to 60 is okay.
Guess I'll use the inbetween time to do more sanding or work on the neck or something
Ehh, the climate here is pretty much fail, but at least it doesnt rain quite as much as Britain
If you were using Nitro you could spray with the humidity and use blush eraser to get rid of the blushing caused by the water that is drawn out of the air. You could build a small spray booth out of a refrigerator box and heat it with a lightbulb to reduce humidity inside. If you do that make sure you leave a couple small vent holes in the top of the box. Also make sure the light has some sort of globe around it to keep the fumes from direct contact with it just to be safe.