An Investigation of the Synoptic Situations Associated with Major Wildland Fires

Fifty-two major wildland fires in the eastern half of the United States were analyzed to determine the synoptic situations involved. Three-fourths of the fires were found near surface frontal areas. The vast majority of fires were associated with the eastern portion of small-amplitude but intense short-wave troughs at 500 mb. A lack of moisture advection at 850 mb inhibits precipitation which normally accompanies these systems. This lack of precipitation in association with strong low-level winds found in these regions produces dangerous fire conditions at the surface. Such situations are shown to occur rarely.