During the hottest period, the average high temperatures are generally between 36 and 42 °C (97 and 108 °F) (and even more in the hottest regions), often for more than three months, while the average low temperatures are around 25 to 31 °C (77 to 88 °F). During the "coldest period", the average high temperatures are between 27 and 33 °C (81 and 91 °F) and the average low temperatures are between 15 and 21 °C (59 and 70 °F). Everywhere in the Sahel, the average mean temperature is over 18 °C (64 °F).