The "Albuquerque Box"
Source: Albuquerque International Balloon Festival
The famous "Albuquerque Box" in the ballooning community is a terrain-influenced feature. During the Fall months the predominant wind direction in the lower atmosphere is from the South or Southwest. The southwesterly wind occurs quite often during the afternoon in the Albuquerque area. However in the mornings, especially during the mornings after a fairly cloud-free sky overnight, a significant temperature inversion is present where the coldest air is near the surface. This cold and dense air from the higher terrain north of Balloon Fiesta Park "pours" down the valley through Balloon Fiesta, thus the surface wind in the morning hours is typically from the North while the wind direction above the surface remains from the predominant southerly direction. This wind from the North near the surface and from the South above the surface forms the infamous "Albuquerque Box". With a little luck, this enables ballonists to lift-off, float south, increase altitude and return north to land back at the starting point. When the sunlight comes over the Sandia mountain range and heats up the lower atmosphere the temperature inversion is lost and the entire atmosphere mixes, thus the southerly wind from above extends to lower altitudes and the Albuquerque Box dissipates.
