I had one of these before and it seemed to do the job...
Weather Station
I liked it because you could position the different sensors in different places (i.e. the wind sensors should be as high as possible, but temperature sensor should be 2m off the ground).
It worked well until I moved house and the removal people smashed all the cups off the anemometer! The temperature always seemed to be fairly accurate (unless it got really hot in the summer, but I think that was to do with where it was positioned).