The accurite digital weather station is a great option. It is actually an indoor outdoor household thermometer but it works great for single setups. It has an external probe that measures "outdoor" temperature (which you can use to measure your hotside) and the unit measures "indoor" temperature and humidity (which can measure your ambient temps and humidity). You can find this unit at the home depot, lowes, or walmart. It costs about $12 and is well worth the money.