Riyadh has a hot desert climate (Köppen Climate Classification ''BWh''), with long, extremely hot summers and short, very mild winters. The average high temperature in August is . If it was not for the elevation the city was on, Riyadh would experience an even hotter climate. The city experiences very little precipitation, especially in summer, but receives a fair amount of rain in March and April. It is also known to have dust storms during which the dust can be so thick that visibility is under . On 1 and 2 April 2015, a massive dust storm hit Riyadh, causing suspension of classes in many schools in the area and cancellation of hundreds of flights, both domestic and international.