Mid to upper 90's here, not sure what the humidity is, but, when I went out to mow grass at 3 pm, it was still wet with dew. Mowed anyway, at least mower was working better, put new belts and idler pulley on the deck, and sharpened the blades. I think the old ones needed replacing for a long time. I think they have been bad enough they were slipping, blades seem to turn faster and cut better.