The Karakum Desert is one of the driest deserts in the world; some places have an average annual precipitation of only . The highest temperature recorded in Ashgabat is  and Kerki, an extreme inland city located on the banks of the Amu Darya river, recorded  in July 1983, although this value is unofficial.  is the highest temperature recorded at Repetek Reserve, recognized as the highest temperature ever recorded in the whole former Soviet Union. Turkmenistan enjoys 235-240 sunny days per year. The average number of degree days ranges from 4500 to 5000 Celsius, sufficient for production of extra long staple cotton.