April among coolest months

According to the National Climatic Data Center, April was a full degree Fahrenheit cooler than the 20th Century average. This wouldn't be a big deal, except that about now, according to Al Gore, we should start to feel the Earth's fever stating to boil over. So what's with the dropping temperature? Especially when we had not decades but mere years, and perhaps not even that much, to prevent the planet's death by fever. This ought to buy us a few more days, right?