Tropical systems played a key role in moistening parts of the nation but bypassed a broad area stretching from the central Gulf Coast states into the Ohio Valley. Eight named tropical systems (four tropical storms and four hurricanes) formed over the Atlantic Basin during the month, tying a September record originally set in 2002.
Warm weather dominated the United States during September, except across portions of the nation's northern tier. Late-season warmth was most impressive in the Southwest and Southeast, while unusually cool conditions stretched from the northern Plains into the Great Lakes States.
Earl to the East
Early in the month, Hurricane Earl dealt a glancing blow to the East Coast, grazing North Carolina's Outer Banks and coastal New England on September 2–3 before racing ashore in Nova Scotia, Canada, as a strong tropical storm on September 4. Before dawn on September 3, Hurricane Earl passed about 85 miles east of Cape Hatteras, North Carolina, with maximum sustained winds near 105 mph. September 2–3 rainfall totaled 4.52 inches at Cape Hatteras.
Later, Tropical Storm Earl passed about 90 miles south-southeast of Nantucket, Massachusetts, shortly before midnight on September 3, with sustained winds near 70 mph. September 3–4 rainfall totaled 4.47 inches in Hyannis, Massachusetts. Bangor, Maine, received 3.46 inches of rain during the first four days of the month, including a daily record total of 3.31 inches on September 4.
Weatherwise Contributing Editor BRAD RIPPEY is the U.S. Editor of the Weekly Weather and Crop Bulletin of the Joint Agriculture NOAA Weather Facility.
Weatherwise Contributing Editor JEFFREY B. HALVERSON is an associate professor of geography at the University of Maryland, Baltimore County. He was a Mission Scientist during NASA's GRIP experiment and is on the NASA Global Hawk hurricane research team.