The weather in Pembrokeshire is surprisingly good, as a result of being on the Peninsula and benefitting from the warmth of the Gulf stream.
The winters tend to be warmer than inland (+3-5degrees), with very few frosts... and summers are usually a little cooler (-3-5 degrees).
It's very difficult to trust the forecast as, very often, a prediction of cloud and rain for the general area will end up being sunny in St Davids, as we're so close to the sea.... just a few minutes walk, so clouds gather inland, whilst we're bathed in sunshine! Not all the time, but quite often!