Drought is a major environmental hazard affecting agriculture and other socio-economic activities globally but most prominent in the arid and semi-arid zones. This study examined drought characteristics in the semi-arid tropics of Nigeria from 1981 to 2012. Standardized Precipitation Index-12 series analysis, drought magnitude index, drought probability index, recurrence interval and descriptive statistics were employed for the study. The results showed a decline in drought frequency from 58.9% mild to 5.1% extreme, a variation of 0 to 28 times for individual drought category and 21 to 46 times for its total. The northeastern area (Pokistum and Maiduguri - 53.8%) is the most notorious for extreme drought events. Pokistum and Yelwa contributed 47.25% of the entire extreme droughts magnitude in the zone. Drought intensity is from -0.01 to -4.49 on SPI scale with the highest at Nguru in June 2004. Drought duration is a mix of various categories with the lowest of one month in a few stations and highest of about seven years (80 months) at Kano from December 1981 to July 1988. The absolute probability and the recurrence interval ranged from 0 to 0.70 and 0 to 33.3 years respectively. The droughts demonstrated extensive monthly inconsistency exemplified by fluctuation.