Abstract
A tropical squall line that passed over the ship array of the Global Atmospheric Research Programme's Atlantic Tropical Experiment (GATE) on 9-10 August 1974 is analyzed. This squall line was similar to squall systems that passed over the GATE ship array on four other days. It began as a purely convective cloud line, then developed an associated stratiform cloud and precipitation area. The stratiform rain built up to a maximum amount over a period of 8 h, then gradually diminished over a 6 h period. This stratiform rain is estimated to have accounted for 32% of the squall system's total precipitation. As in other GATE squall lines, the upper-level cloud shield from which the stratiform rain fell, was advected slowly forward of the line during the system's lifetime, the leading line of convective clouds consisted of transient smaller-scale convective elements, which lent the line an irregular shape and pulsatory movement, and the stratiform portion of the system was characterized by the development of a mid-level mesoscale vortex similar to that seen in other GATE cases.
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Tongjian, W., Houze, R.A. The GATE squall line of 9-10 August 1974. Adv. Atmos. Sci. 4, 85–92 (1987). https://doi.org/10.1007/BF02656664
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DOI: https://doi.org/10.1007/BF02656664