Sequences or bursts of uniform pulses have been recorded during a large fraction of intracloud lightning discharges in Florida and Arizona. The wave form of a typical pulse begins with a fast, large amplitude portion followed by a small and slowly varying overshoot. The full width at half maximum of the large amplitude peak is typically 0.75 μs, and the time intervals between pulses are typically 5 μs, in both maritime and continental storms. The pulse shapes and interval times suggest that the source of these pulses is an intracloud dart-stepped leader process similar to that which has been photographed in discharges to ground.