Abnormally Warm September Concludes


September 2018 was a remarkable month for warmth in the eastern United States. Its generally persistent warmth provided yet another case demonstrating that September has increasingly become an extension of summer more than the start of fall in recent years.

In the New York City area, the last week of September had an average temperature of 63.6° prior to 1980. Since 1980, it has had an average temperature of 64.6°. Since 2000, that figure has climbed further to 65.9°. That is essentially the same as the average temperature was for the preceding seven days prior to 1980. Then, the average temperature was 66.1°. Records for Central Park go back to 1869.

The warmth was present up and down the Eastern Seaboard. September monthly average temperature data for select cities follows:
Albany: 67.2° (8th warmest)
Asheville: 74.1° (old record: 73.6°, 1925)
Atlanta: 80.9° (2nd warmest)
Baltimore: 73.0° (11th warmest)
Boston: 69.0° (5th warmest)
Burlington: 65.7° (2nd warmest)
Charleston: 81.5° (old record: 79.8°, 1980 and 2016)
Charlotte: 78.9° (3rd warmest)
Columbia: 81.9° (2nd warmest)
Concord: 64.6° (6th warmest)
Jacksonville: 82.4° (2nd warmest)
Key West: 85.8° (old record: 85.2°, 1951)
Miami: 83.3° (12th warmest)
New York City: 70.7° (21st warmest) — record 4th consecutive September with a mean temperature of 70° or above
Newark: 71.4° (9th warmest)
Norfolk: 79.1° (old record: 78.2°, 1881)
Orlando: 83.4° (3rd warmest)
Philadelphia: 72.5° (9th warmest)
Portland: 63.6° (10th warmest)
Raleigh: 76.9° (4th warmest)
Richmond: 76.4° (2nd warmest)
Savannah: 81.8° (3rd warmest)
Tallahassee: 82.7° (2nd warmest)
Tampa: 85.9° (old record: 83.8°, 2016) — warmest month on record
Washington, DC: 75.5° (6th warmest)
Wilmington, NC: 79.2° (tied record set in 1921)