Cleaning in the rain divides people on here. I'm wfp and have been since I started in 2009. I was determined to clean in the rain at first, but within a few months I changed my mind. 2 reasons - a) I didn't enjoy it, and b) comments from my custies.
Now before you all jump on me I live on a (non-profit making) smallholding 900 feet up in the Preselis, west Wales. I'm well aquainted with all types of precipitation, most of which falls horizontally, and I don't mind it - to a point. More seriously when my custies started exclaiming "You're not going to clean them in THIS are you" I had to reappraise my business approach.
I am a window cleaner but I see myself also as being in the customer service business - I want my customers to be happy to see me every time - so getting the frequency and price right and doing a good job every time is essential. Before this I worked in travel, planning all types of adventure holidays all over the Middle East and Asia. If people told us that they didn't like an aspect of a trip, or a hotel we listened and changed things, even if we didn't agree with their opinions or if it removed some of the adventure from the adventure trip they booked.
Similarly if my custies are going to begrudge paying me for cleaning windows if it was raining I had to listen. I upped my prices a little and built in wet days - like today - it's raining right now and here I am on CIU. If it stops i'll go out. Incidentally I find I have very few people comment "Leave it, it's going to rain".
Whatever people on here say rain can make windows dirty. It depends on the location of the property, how close the frontage is to a road, how busy that road is, the time of year and whether it's been warm/hot and dry for a while, and which way the rain comes from. I'd love someone to offer me a rain guarantee on my house - i'm on a main road where traffic does 50/60mph. We are 40 feet back from the road, but the spray blown on our windows would mean any WC offering such a guarantee would never be away at some times of the year. Again, if there is a hot dry spell and a southerly wind brings rain holding dust from the Continent, well you might get some spotting, like on cars. It would be fine i'm guessing on your average housing estate, with little, slow moving traffic - you could train your custies as lads on here say and get away with it.
At the end of the day it depends on each individual and there needs - there is no one size fits all business models.
Personally I prefer to stay dry-ish. I clean in light rain, but as soon as it's anything more than that and I rethink things, taking into account the jobs I have on. When it was hot in July I turned up at someone's place and she said "You're not going to clean in THIS are you?". I asked what she meant and she said, "It's too dry and hot". I really had to bite my tongue but I just laughed it off and carried on.
I use this website and find it very accurate - better than Metcheck and Netweather:
http://www.yr.no/ You'll have to choose English and put in your location. Explore it, it's good. Also useful is this:
http://www.rain-alarm.com/?from=sidebar It's a rain radar showing where rain is moving.
Cheers