Sometimes the system we use really baffles me. I did a maintenance clean the other week in very poor weather, being dry, but not able to move the pole an inch because it was so windy. Clean was okay, but had spots here and there.
Did a clean two days ago, first clean, tremendous downpour with really bad winds, and windows came up lovely.
Gotta love wfp, too many variables and unexplained results sometimes.
I think downpours aren't always that bad, since there isn't a lot of dust coming off the fields etc, but the wind can be tricky.
Oh well, I just go out and go for it, bills to be paid.