Nope, wasn't accurate at all for me! Mine started at 30 degrees then 28 and beautiful, then 20, then 18 and it was 20 and rained after the photos/ceremony. I constantly checked it and on the day it didn't even matter what it was, I didnt even notice.
i wouldn't rely solely on these. most of the time the weather man cant even predict the weather! lol. i would use it for a guage only... i would have a look at the satelite picture you should then be able to see what kind of weather will be comming by the cloud bands etc. but as we all know the weather can be unpredictable especially with the weird weather we have been haing lately!
I turned into a crazy person checking the weather forecast. the day turned out perfect. prior to the day, it was forecast to be overcast and rainy. save the stress and go with the flow and try not to worry!
Mine was accurate, but it was fairly normal weather for Perth at that time of year, so it wasn't a major surprise! It certainly didn't predict the bushfire that almost caused our wedding to be evacuated!