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Daily rainfall, wind, and omega datasets over the global tropics are analysed to characterize raifall intraseasonal variability over the Nordeste of Brazil. This work presents observational evidence that the temporal distribution of rainfall over Nordeste during the wet periods of 1998 to 2000 were modulated by planetary scale atmospheric oscillations detected along the tropics over both the Pacific and Atlantic Basins. Eastward propagating pulses of tropical convection reached the tropical Atlantic Ocean with periods ranging from 30 to 60 days. The negative phases of such pulses (associated with subsidence and suppression of rainfall) reached the Nordeste during the peak of the rainy season over the area, contributing to reducing the total seasonal rainfall totals substantially. The analyses also show that the pulses have a essentially baroclinic vertical structure, with convergence/divergence in lower levels aligned with divergence/convergence in upper levels of the troposphere, thus strongly modulating deep cummulus convection over the Nordeste. It is also shown that while the intraseasonal variability can be detected during all the three years analysed, its effect is largest in the absence of large scale induced subsidence over the region, as that associated with the 1998 ENSO event.