Rwanda lies within the equatorial zone, but has sizeable mountains and hills that moderate its climate and cause it to be more temperate. Generally, rainfall follows a gradient from west to east with the western regions experiencing more annual rainfall than the eastern. The mean annual temperature of Rwanda is around 18°C with maximum temperatures of about 25°C and minimum temperatures of 13°C. There are two rainy seasons and two dry seasons within Rwanda that are controlled by the Inter-Tropical Convergence Zone (ITCZ), as it travels back and forth between the Equator and Tropic of Capricorn throughout the year. One rainy season occurs from March-May and another from September-December. Rwanda receives an average annual rainfall of around 1,295 mm, with the highest monthly rainfall occurring in April, which has an average monthly rainfall total of 157 mm. Key historical climate trends are summarized below:

Temperature

• Observations of mean annual temperature at Kigali Airport and Kamembe meteorological stations shows the average temperature has increased. Temperatures rose by about 1.2°C at Kigali Airport station during 1971-2009 and similar values were seen at the Kamembe station.
• Rwanda has experienced a temperature increase of 1.4°C since 1970, higher than the global average (Rwanda Green Growth Strategy, 2011).

Precipitation

• From 1961-1990, observed average monthly and annual precipitation at the meteorological station at Kigali Airport exhibit decreasing trends.
• Mean annual rainfall has declined by 80 mm from 1961 until 2006 at the Kigali Airport meteorological station.
• Observations of the extent of the rainy seasons (March-May and September-November) exhibit a shortening trend.

This section provides the options to visualize historical climate data for different timeframes via map and annual cycle chart.