I have a Maplin’s UBS Pro weather station (£60 from Maplins – if the black one is expensive the white one is cheap).
http://www.maplin.co.uk/p/black-usb-wireless-touchscreen-weather-forecaster-n96gy
Records temp, rainfall, wind speed and direction and relative humidity. Awesome!
I plugged mine into a Raspberry Pi (which plugs into the base station via a USB cable – sitting neatly in the living room)
I then installed pywws (Python) using the guide on this website:
http://www.weather.dragontail.co.uk/index.php?page=station_setup
It feeds every 5 minutes to Weather Underground:
http://www.wunderground.com/personal-weather-station/dashboard?ID=ISTIRLIN11#current
If going for more than an overnight min/max – which is a bit boring really 😉 think about how you’re going to view the data. Weather Underground solves the problem for me – else you’ll need a laptop running some logging software. The Maplin’s station comes with some, or there’s software out there on the web for free or a fee.