Judging by last week's forecasts for my region: pretty far off. Sudden rain in the regions of 10mm/m² and a lot of clouds when sunny weather was predicted. The exact opposite happened as well. Temperatures were off by 5-8°C, too.

All of this for same day forecasts, not even 2 days in advance.

rain is pretty hard to predict though. I guess what matters the most is if you can reliably predict major events like heavy storms rather than if you will get a bit wet later today.