Annual rainfall generally decreases from the coast inland from an average of about 3000 mm in Warri on the coast to less than 500 mm in Nguru in the Sahel of the north-east. However, rainfall is mostly seasonal- in the south, the wet season extends from March to October, while it is May to September in the north. Temperatures are more or less moderate throughout the year except in one or two months when the dry cold north-easterly wind dominates the wind system. (Second National Communication, 2014)
- The southern part of Nigeria has seen a larger increase in mean temperature than the north during the period of 1961-1990.
- Average maximum temperatures have been increasing in Nigeria with maximum temperatures ranging between 31-33° C.
- The annual number of ‘hot’ nights and ‘hot’ days has increased in Nigeria between 1960-2003; ‘hot’ days have increased by 73 days between 1960-2003 with the rate strongest during September-November.
- ‘Cold’ days and nights have decreased between 1960-2003. The annual average number of ‘cold’ nights has decreased by 45 (statistically significant), with the strongest rate of decrease seen during September-November.
- Average precipitation per year has decreased significantly in Nigeria by 3.5 mm per month per decade between 1960-2006.
- The period of the maximum in the north may have shifted from August to July and the primary rainfall peak in the south from July to September.
- Also, the high intra-annual variability of Nigeria’s rainfall is becoming more prominent.
This section provides the options to visualize historical climate data for different timeframes via map and annual cycle chart.