<P> Ibadan is located in south - western Nigeria in the southeastern part of Oyo State at about 119 kilometres (74 miles) northeast of Lagos and 120 kilometres (75 miles) east of the Nigerian international border with the Republic of Benin . It lies completely within the tropical forest zone but close to the boundary between the forest and the derived savanna . The city ranges in elevation from 150 m in the valley area, to 275 m above sea level on the major north - south ridge which crosses the central part of the city . The city covers a total area of 3,080 square kilometres (1,190 sq mi), the largest in Nigeria . </P> <P> The city of Ibadan is naturally drained by four rivers with many tributaries: Ona River in the North and West; Ogbere River towards the East; Ogunpa River flowing through the city and Kudeti River in the Central part of the metropolis . Ogunpa River, a third - order stream with a channel length of 12.76 km and a catchment area of 54.92 km . Lake Eleyele is located at the northwestern part of the city, while the Osun River and the Asejire Lake bounds the city to the east . </P> <P> Ibadan has a tropical wet and dry climate (Köppen climate classification Aw), with a lengthy wet season and relatively constant temperatures throughout the course of the year . Ibadan's wet season runs from March through October, though August sees somewhat of a lull in precipitation . This lull nearly divides the wet season into two different wet seasons . November to February forms the city's dry season, during which Ibadan experiences the typical West African harmattan . The mean total rainfall for Ibadan is 1420.06 mm, falling in approximately 109 days . There are two peaks for rainfall, June and September . The mean maximum temperature is 26.46 C, minimum 21.42 C and the relative humidity is 74.55% . </P> <Table> <Tr> <Th_colspan="14"> (hide) Climate data for Ibadan </Th> </Tr> <Tr> <Th> Month </Th> <Th> Jan </Th> <Th> Feb </Th> <Th> Mar </Th> <Th> Apr </Th> <Th> May </Th> <Th> Jun </Th> <Th> Jul </Th> <Th> Aug </Th> <Th> Sep </Th> <Th> Oct </Th> <Th> Nov </Th> <Th> Dec </Th> <Th> Year </Th> </Tr> <Tr> <Th> Record high ° C (° F) </Th> <Td> 37.2 (99) </Td> <Td> 38.9 (102) </Td> <Td> 38.3 (100.9) </Td> <Td> 37.2 (99) </Td> <Td> 35.0 (95) </Td> <Td> 33.3 (91.9) </Td> <Td> 31.7 (89.1) </Td> <Td> 31.7 (89.1) </Td> <Td> 35.6 (96.1) </Td> <Td> 33.3 (91.9) </Td> <Td> 33.9 (93) </Td> <Td> 35.6 (96.1) </Td> <Td> 38.9 (102) </Td> </Tr> <Tr> <Th> Average high ° C (° F) </Th> <Td> 32.3 (90.1) </Td> <Td> 34.0 (93.2) </Td> <Td> 33.5 (92.3) </Td> <Td> 32.3 (90.1) </Td> <Td> 31.2 (88.2) </Td> <Td> 29.6 (85.3) </Td> <Td> 27.8 (82) </Td> <Td> 27.2 (81) </Td> <Td> 28.5 (83.3) </Td> <Td> 29.7 (85.5) </Td> <Td> 31.3 (88.3) </Td> <Td> 31.9 (89.4) </Td> <Td> 30.8 (87.4) </Td> </Tr> <Tr> <Th> Daily mean ° C (° F) </Th> <Td> 25.7 (78.3) </Td> <Td> 26.9 (80.4) </Td> <Td> 26.9 (80.4) </Td> <Td> 26.3 (79.3) </Td> <Td> 25.6 (78.1) </Td> <Td> 25.1 (77.2) </Td> <Td> 23.6 (74.5) </Td> <Td> 23.1 (73.6) </Td> <Td> 23.9 (75) </Td> <Td> 24.3 (75.7) </Td> <Td> 25.6 (78.1) </Td> <Td> 25.5 (77.9) </Td> <Td> 25.2 (77.4) </Td> </Tr> <Tr> <Th> Average low ° C (° F) </Th> <Td> 20.9 (69.6) </Td> <Td> 21.9 (71.4) </Td> <Td> 22.5 (72.5) </Td> <Td> 22.0 (71.6) </Td> <Td> 21.7 (71.1) </Td> <Td> 21.6 (70.9) </Td> <Td> 21.2 (70.2) </Td> <Td> 20.7 (69.3) </Td> <Td> 21.8 (71.2) </Td> <Td> 21.7 (71.1) </Td> <Td> 21.6 (70.9) </Td> <Td> 20.7 (69.3) </Td> <Td> 21.5 (70.7) </Td> </Tr> <Tr> <Th> Record low ° C (° F) </Th> <Td> 10.0 (50) </Td> <Td> 11.1 (52) </Td> <Td> 15.0 (59) </Td> <Td> 18.3 (64.9) </Td> <Td> 17.8 (64) </Td> <Td> 17.8 (64) </Td> <Td> 16.1 (61) </Td> <Td> 15.6 (60.1) </Td> <Td> 17.2 (63) </Td> <Td> 17.8 (64) </Td> <Td> 15.6 (60.1) </Td> <Td> 11.1 (52) </Td> <Td> 10.0 (50) </Td> </Tr> <Tr> <Th> Average rainfall mm (inches) </Th> <Td> 10 (0.39) </Td> <Td> 25 (0.98) </Td> <Td> 91 (3.58) </Td> <Td> 135 (5.31) </Td> <Td> 152 (5.98) </Td> <Td> 188 (7.4) </Td> <Td> 155 (6.1) </Td> <Td> 86 (3.39) </Td> <Td> 175 (6.89) </Td> <Td> 160 (6.3) </Td> <Td> 46 (1.81) </Td> <Td> 10 (0.39) </Td> <Td> 1,233 (48.54) </Td> </Tr> <Tr> <Th> Average rainy days (≥ 0.3 mm) </Th> <Td> </Td> <Td> </Td> <Td> 7 </Td> <Td> 9 </Td> <Td> 14 </Td> <Td> 17 </Td> <Td> 15 </Td> <Td> 13 </Td> <Td> 18 </Td> <Td> 18 </Td> <Td> 7 </Td> <Td> </Td> <Td> 123 </Td> </Tr> <Tr> <Th> Average relative humidity (%) </Th> <Td> 76 </Td> <Td> 73 </Td> <Td> 77 </Td> <Td> 82 </Td> <Td> 85 </Td> <Td> 87 </Td> <Td> 89 </Td> <Td> 88 </Td> <Td> 88 </Td> <Td> 87 </Td> <Td> 83 </Td> <Td> 79 </Td> <Td> 83 </Td> </Tr> <Tr> <Th> Mean monthly sunshine hours </Th> <Td> 198.4 </Td> <Td> 197.8 </Td> <Td> 186.0 </Td> <Td> 180.0 </Td> <Td> 195.3 </Td> <Td> 147.0 </Td> <Td> 86.8 </Td> <Td> 65.1 </Td> <Td> 93.0 </Td> <Td> 164.3 </Td> <Td> 207.0 </Td> <Td> 220.1 </Td> <Td> 1,940.8 </Td> </Tr> <Tr> <Th> Mean daily sunshine hours </Th> <Td> 6.4 </Td> <Td> 7.0 </Td> <Td> 6.0 </Td> <Td> 6.0 </Td> <Td> 6.3 </Td> <Td> 4.9 </Td> <Td> 2.8 </Td> <Td> 2.1 </Td> <Td> 3.1 </Td> <Td> 5.3 </Td> <Td> 6.9 </Td> <Td> 7.1 </Td> <Td> 5.3 </Td> </Tr> <Tr> <Td_colspan="14"> Source: Deutscher Wetterdienst </Td> </Tr> </Table>

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