The 7.3 µm “Lower-level water vapor” band typically senses farthest down into the mid-troposphere in cloud-free regions. It is used to track lower tropospheric winds, identify jet streaks, monitor severe weather potential, estimate lower-level moisture, identify regions where the potential for turbulence exists, highlight volcanic plumes that are rich in sulphur dioxide (SO2) and track Lake Effect snow bands. In this imagery, bright blue and white areas indicate the presence of high water vapor or moisture content, whereas dark orange and brown areas indicate little or no moisture present.
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