Rare rainfall event in Sahara Desert

The Sahara Desert is the driest place on Earth, but it's about to receive over 500% its monthly rainfall.

Rainfall events in the Sahara don't come around often, in fact less than once a decade on average. The Sahara Desert receives little to no precipitation all year.

This figure is around 3 inches on average, though over half the desert only sees an average of an inch of rainfall per year, making it the driest place on the planet.

It is because of the atmospheric patterns that it is this way. The Sahara Desert sits under a subtropical ridge; a semi-permanent high pressure system, meaning dry, stable air descends, preventing cloud formation and precipitation.

However, the ITCZ, the Inter-Tropical Convergence Zone, a permanent low pressure belt of rainfall spread across the equator, has been shifting north in recent months.

This has knock-on effects across the globe in terms of weather patterns, but also means that rainfall is being driven into the Sahara. Heavy rain and storms are in the forecast for the desert over the next few weeks.

While the rainfall amounts relative to other parts of the world may not seem significant, it is over 500% as much as the Sahara's monthly rainfall for August and September, and as much as 1000% for some central regions.