GOES-9 Super Rapid Scan Observations were used to monitor minute to minute changes in fire characteristics for several large fires burning in the Western US on 16 August 1996. Fires A, B, C, and D were monitored at 1-minute intervals from 0122 to 0139 UTC. Time series of the 3.9 and 10.7 micron observations of brightness temperatures for the fire pixels (T4 and T11, respectively) and nearby background non-fire pixels (TB4 and TB11, respectively) provide insight on changes in fire size/intensity. Fire pixels B and C remain fairly constant while fire pixels A and D show rapid fluctuations from one time period to the next representing changes in sub-pixel fire size/intensity.