GATE rainfall and its relationship to easterly waves

Rainfall rate data from the three Phases of GATE are examined in relation to tropical easterly wave passages. Power spectra of rainfall and 700-mb meridional winds are performed. Precipitation is found to be highly correlated to easterly wave trough passages. In addition, a diurnal variation is also found in the rainfall data. Total accumulated rainfall and mean rainfall rates are examined in terms of wave category, and rainfall is once again seen to be modulated by wave trough passages. However, significant rainfall is found outside the wave trough as well. A waveby- wave examination of the data shows that rainfall occurs in association with squall lines, deformation in the 700-mb wind field, and ITCZ convection, in addition to precipitating cloud clusters in the wave trough. The results indicate that rainfall is consistently associated with organized wave features during all three Phases.