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Abstract
In warm, moist Gulf airmasses, temperature and relative humidity on an exposed ridgetop were similar to those in a nearby valley. In cooler Canadian and Pacific airmasses, afternoon measurements at the two locations were about the same, but during the night the ridgetop averaged 8 °F. warmer and 27 percentage points drier than the valley.
Citation
Gwinner, Myron W. 1965. Forest-fire danger as related to airmass in the Ouachita Mountains. Res. Note SO-21. New Orleans, LA: U.S. Department of Agriculture, Forest Service, Southern Forest Experiment Station. 4 p.