Pilot Balloon Observation (PIBAL) 1
Pilot Balloon Observation (PIBAL) 1 : A method of determining winds aloft in the vicinity of an observation station by periodically reading the elevation and azimuth angles of a theodolite, usually at 1-minute intervals, while optically tracking the ascent of a small free-lift balloon. A PIBAL is commonly used for constructing a vertical wind profile. Note: Minisonde and Rawinsonde Observations