As you can see in the RED column, 2012 takes top spot on Houston's climate list for warmest year. By far, the heat during the summers of 2011 and 2010 were MUCH higher than 2012. But 2012 tops all other years because of so many warmer nights throughout all the seasons coupled with average highs throughout the year. It seemed like a cooler year only because of the sweltering summers and record droughts the year before.
My zone 9 garden was actually a zone 10a garden with no freezes in early 2012 and no freezes in late 2012. For a tropical gardener, it's a nice year when you don't have to put all your plants in the greenhouse. But for the planet, I do worry about the changes to our climate.
Here's my annual monthly chart for 2012.