Two days before the attack, the Sunday edition of The New York Times reported “Fall is the city’s most glorious season with clear skies and a crackle in the air.” It proclaimed perfect weather “means visitors pour into town ... residents stay put until the moment summer evaporates.” The opening line in the official 9/11 Commission report was, “Tuesday, September 11, 2001, dawned temperate and nearly cloudless in the eastern United States.” The report stated, “For those heading to an airport, weather conditions could not have been better for a safe, pleasant journey.” One section, titled “Focus,” included a writeup called “Hurricane Day,” explaining how in nine out of 10 years since 1886, one tropical storm or hurricane has raged in the Atlantic on Sept. 11.

Fastcast: More clouds.