Heavy wind + heavy rain, give up!
Showers or light rain and light winds, no problem, you can work in conditions that would stop you if you were using traditional methods.
But the higher you go, the more the wind will have an effect, but again, I rarely think about the wind now, there are days when there is no way I would climb a ladder, but don't give it so much as a second thought with WFP.
I'm sat on my arse at the mo, raining quite heavy at times and very windy too, so for me that is a combination that will not leave the windows I clean in a good conditioin, well, with domestic at any rate,commercial stuff I carry on regardless of conditions.
Well, ok, maybe not regardless, but the conditions have to be pretty extreme to stop me cleaning my shops
Live long, and prosper
Ian