Wildfires - September 2006
Although drought persisted in the middle of the country in September, large wildland fire activity was concentrated in the northwest U.S. and Canada.
As of end of September, there have been about 84,000 wildland fires across the Lower 48 States since the beginning of 2006, and over 9 million acres were burned, according to estimates from the National Interagency Fire Center. The preliminary number of acres burned so far this year in the U.S. is a record for an entire year. Over half of the fires and a quarter of the burned acreage occurred in the Southern Area (which encompasses 13 states, Puerto Rico, the Virgin Islands and the District of Columbia).
|Totals as of early October||Nationwide Number of Fires||Nationwide Number of Acres Burned|
Medium to larger fuels (i.e., the September 30 100–hr and September 30 1000–hr fuel moistures) remained unusually dry over the past month from the California–Arizona–Mexico border northward into Utah, Oregon and Idaho.
The Keetch–Byram Drought Index (KBDI), a widely used index for fire risk, had the largest potential for wildland fire activity in the contiguous U.S. along the West Coast and in the South from Texas to Georgia by the end of the month. In addition, the observed experimental fire potential index at the end of September was anomalously high for one large area from southern California and Arizona northward into Oregon, Idaho and Wyoming.
Historically, the graphs below show that in the lower 48 states, the number of fires has been decreasing since the 1980s. However, the number of acres burned has been increasing. In Alaska the pattern is similar to the lower 48 states, but the number of fires was the highest in the early 1990s.