I can see the problem with the wet clothes.
but washing windows during rainy day is to me, a normal
thing.
since it is rainy, just close the windows for 10-15 mins.
Like one reader commented, imagine if she is doing it during
non-rainy days, then your head will swell.
just try to talk to her if you spot her at nearby coffeeshop or
grocery stall or NTUC.
but always start with defensive rather than offensive so give the
neighbour some space so can work this out.