If a region receives more than 10 inches (250 mm) of precipitation on average per year it is not considered a desert.
Deserts are defined as regions that receive less than 10 inches (250 mm) of rainfall on average annually.
32.5
The amount of rainfall in England varies by region. However, the average amount of rain for the entire country is 33.7 inches, or 885 millimeters.
650-750in
Victoria's average annual rainfall is 37.41 inches
59" to 200"
Dubai receives an average annual rainfall of about 3.7 inches (94 mm). This amount of rainfall is considered quite low, making Dubai a desert climate with arid conditions. Rainfall mostly occurs during the winter months and is sporadic.
According to Encarta, the lowest yearly average rainfall in Africa occurs in Wadt Halfa, Sudan. The average amount annually is 3mm or .1 inch.
Average rainfall is typically measured using a rain gauge, a container designed to collect and measure the amount of precipitation that falls over a specific period of time. The total amount of rainfall collected in the rain gauge is then divided by the number of days in the period to determine the average daily rainfall.
'bout 500 mm
42 inches in Cardiff
There is no minimum amount as some deserts go centuries with no measurable rainfall. The maximum is 10 inches (250 mm). More than 10 inches average in a year moves the region into the steppe climate.