New Normal Climate: Nights Are Warmer

It doesn't take a meteorologist to tell you that temperatures are rising year after year, across the U.S. The most noticeable change over the last 30 years involves overnight lows. Overnight lows are averaging a whole degree warmer across many parts of the North. Nighttime temperatures set the stage for what happens the next day weather-wise. With warmer nights, fire season is longer. Pollination patterns may be changing. A study sponsored by Longwood Gardens showed that flowering plants have been blooming an average of one day earlier each decade. Warmer nights and later onset of freezing days also means that plants can generally survive farther north than they used to.

Average Minimum Temperature

Pests are also able to thrive and spread in forests and other natural landscapes at least in part because of warmer nights. Both the native pine bark beetle, which has ravaged forests from Colorado to Alaska, and the introduced wooly adelgid, which has been sucking the life out of hemlocks in the East, may be benefiting from warmer nights, especially in winter.