I use this excel sheet to graph the weather each day. Simply copy the rectangle under the weather, and paste it in its column to form a bar graph. Every month, save and print the weather, then start fresh with a new sheet. You can then compare weather in September to weather in January to weather in April. Make sure page layout is landscape and margins are set to "narrow" before printing!
I project this excel sheet onto our smartboard, so that the students can see the data and count/analyze as the month goes on. I ask the "Weather Helper" questions like "What's the temperature today?" and then I input the data. I allow students to choose "both" for cloudy and sunny if they think that's the case. If you want to add a "partly cloudy" option to your graph, feel free!