Philadelphia and Allentown also just missed posting their warmest October, placing second. Philadelphia’s average temperature of 64.1 degrees was a shade below the record-setting 64.5 degrees set in 2007. Allentown missed its record, also set in 2007, by 0.7 degrees.
The warmer-than-normal air set up in the Northeast due to a semi-persistent area of high pressure that influenced the region
The unusually warm weather took its toll on fall foliage, which was described as duller than normal. Clear, cold nights are deemed optimal for vibrant foliage and, more often than not, it was warm and wet.
The Southeast U.S. wasn’t as warm relative to normal as the Northeast, but most locations still experienced one of their top 10 warmest Octobers.
The abnormally warm October in the Northeast is part of a long-term trend. CBS Boston meteorologist Eric Fisher wrote the Blue Hill Observatory outside Boston, which recorded its warmest October, has now observed its warmest April, July, August, September, October, November, December, spring, summer, fall, winter and year on record since 2010.