Throughout this analysis, I have often referred to the fact that the ground temperatures was only 1341F/727C on September 16 and 23. The evidence for this comes from the USGS Thermal scans of the area. You may view the report here:

OFR 01-0429: World Trade Center USGS Thermal

In addition, you may also observe for yourself how the temperature decreases over this time span via the associated thermal imagery for that time period:

WTC – Thermal Imagery, September 16, 2001. New York State, Office for Technology (c2001) and EarthData International.

WTC – Thermal Imagery, October 18, 2001. New York State, Office for Technology (c2001) and EarthData International.

These facts tell us that there was an additional source of heat, or a localised accelerant of some form, present at all instances documented in this analysis, both before and for months after the attacks.