Stu,
I am not sure that is correct either.... If you have a period of 60 minutes where the wind speed is say 40 km/h from the North but the rest of the day it was 2 km/h varying from NW to NE, does that make the dominant direction North? It's a hard call and I am not sure what the real answer is. I will post a message on the Cumulus forum so see what they believe is the right answer.
As we use 0900hrs as the start of the day here in Aus, then that is what I would use, but others may have a different opinion on that.
BTW, the request for UTC.... The format they expect in the file is yyyy,m,d,h,m,s
The script author has got back to me and asked what changes I have made etc. to which I have replied but as yet have heard nothing further.
I have still been unable to test the rain part of the gauges here as we haven't had any rain since the 20th Dec. I picked a bad time of year to try and get all this working.
Col.