I've been using Wu (Weather Underground) for a while to get local weather readings (temperature, humidity, wind, etc). With all the Raspberry pis in the house, I thought I'd use one to measure weather data at home.
For the pi, I selected a pi 2 that had been replaced by a pi 3 to play videos (the pi 3 just about copes with software x265 decoding at 720p).
I didn't want to do anything complicated for measurements given that I could get local data easily by using one of the neighbouring stations. So I orientated myself toward the Sense Hat (aka Astro Pi). It measures temperature, humidity, atmospheric pressure, the magnetic field, and position in space. That gave me atmospheric pressure on top of what I could already measure with a DHT22 so I went for that.
The Sense Hat is great in terms of hardware integration: all you need is to plug it in and it runs. Then it's a matter of reading the values and doing something with them.