Rain and snow are an essential elements in the Earth"s water cycle, which is critical to every life ~ above Earth. Rainfall is the main way that the water in the skies comes down to Earth, where it fills our lakes and also rivers, recharges the secret aquifers, and provides drinks to plants and also animals.

You are watching: How many inches of rain is a lot


A localized hefty summer rainstorm in Colorado

Here is a standard summer rainstorm; they space often little but intense. Other rain occasions are much more "frontal" in nature, with large nimbostratus varieties of clouds bringing precipitation over a large area. 

Credit: Howard Perlman, invernessgangshow.net

Fortunately because that everyone, water is a renewable source that move in a cycle v neither start nor finish (but, you deserve to put in her vote regarding where friend think it begins). Water vapor (evaporated from oceans, lakes, forests, fields, animals, and plants) condenses and returns to planet as precipitation, as soon as again replenishing reservoirs, lakes, rivers, underground aquifers, and other sources of water and providing the moisture forced by plants and animals... An endless water cycle.

The quantity of precipitation the falls about the human being may selection from less than 0.1 inch per year in some deserts to much more than 900 inches every year in the tropics. One of the driest clues on planet is Iquique, Chile, whereby no rain fell for 14 years. The world"s wettest spot, Mawsynram, in Northeastern India, skilled a average of 494 inches of rain a year throughout the years 1989-2010, instead of the previous placeholder, Cherrapunji, additionally in Northeastern India, whereby a median of 471 inches fell throughout the very same period.

In situation you"re wondering, the wettest ar in the united States, as displayed by data built up by the Western local Climate Center, is top top Mt. Waialeale, Hawaii, wherein an typical of 373 inches of rain has actually fallen annually between the years 1949 and 2008. Mt. Waialeale even experienced more 보다 642 inches of rain indigenous July 1947 come July 1948! If friend think that"s something, Cherrapunji holds the solitary year document of 905 customs measured in 1861!

By contrast, the conterminous (the 48 "lower" states) United claims receives sufficient precipitation throughout an mean year to cover the says to a depth of about 30 inches. This is identical to about 1,430 cubic miles of water every year. What happens to the water after it reaches the ground depends upon numerous factors such as the rate of rainfall, topography, floor condition, thickness of vegetation, temperature, and the degree of urbanization.


Wide spread flooding in Lithia Springs, Georgia just west that downtown Atlanta, after epic rainfall, 22 Sept. 2009. Impervious surfaces and urban buildup reasons rainfall to runoff much quicker, and with greater flooding consequences, throughout heavy rains.

Credit: NASA

For example, the direct runoff in a extremely urbanized area is fairly great, no only due to the fact that of the density of roofs and impermeable pavements permits less rain to infiltrate the ground, but additionally because storm-sewer systems carry more water straight to the streams and lakes. In a an ext natural or undeveloped area, the straight runoff would certainly be significantly less.

In the joined States, an median of part 70 percent that the yearly precipitation returns to the environment by evaporation indigenous land and water surfaces and also by transpiration native vegetation. The remaining 30 percent eventually reaches a stream, lake, or ocean, partly by overland runoff during and also immediately after ~ rain, and partly through a much slower course by relocating though the ground.

Much that the rain that enters the ground filter down into subsurface water-bearing rocks (aquifers) and eventually will lakes, streams, and also rivers whereby these surface-water body intercept the aquifers. The part of the precipitation the reaches the streams produce an average annual streamflow in the United says of roughly 1,200 exchange rate gallons a day. By comparison, the Nations"s homes, farms, and also factories withdraw and also use about 355 billion gallons a job (2010).


Amount the water received as soon as an customs of rain occurs

Have you ever before wondered just how much water drops onto your yard during a rainstorm? utilizing a 1-inch rainstorm together an example, the table below gives example of how much water falls throughout a storm for assorted land areas.


AreaArea (square miles)Area (square kilometers)Amount the water (gallons)Amount the water (liters)
A roof (40 x 70 feet)0.00010.0002571,7436,601
1 acre (1 square mile = 640 acres)0.001560.00427,154102,789
1 square mile12.617,380,00065,780,000
Atlanta, Georgia132.4342.92,293,000,0008,680,000,000
United States3,537,4389,161,92261,474,000,000,000232,700,000,000,000


Consider because that a moment just how much rainwater part cities might receive throughout a year. Because that example, Atlanta, Ga. Averages around 45 inches of precipitation every year; multiply this by the 2.293 billion gallons displayed in the table as the number of gallons in 1 customs reveals that part 103.2 billion gallons that water loss on Atlanta in an typical year. In a city the size of Atlanta, the per capita water use is about 110 gallons per day or 40,150 gallons every year. Thus, the water indigenous a year"s precipitation, if it can be gathered and save on computer without any type of loss, would certainly supply the needs of about 2,574,000 people.




Use our interactive Rainfall Calculator (English units or Metric units)to discover out just how much rain falls on your roof or yard, in her city block, or town.



When it rains, where does that go?

Once on the land, rainfall either seeps into the ground or i do not care runoff, which flows right into rivers and also lakes. What wake up to the rain ~ it drops depends on countless factors together as:

The rate of rainfall: A many rain in a short duration tends to run off the land right into streams fairly than soak right into the ground.The topography the the land: Topography is the place of the floor -- the hills, valleys, mountains, and also canyons. Water fall on uneven land drains downhill until it becomes part of a stream, find a hollow place to accumulate, prefer a lake, or soaks right into the ground.Soil conditions: over there is a many of dense clay in the southeastern United states that rain has a tough time soaking into. Contrast that to the sandy soils in an ext desert areas, which permit water to conveniently be absorbed, at least initially.Density that vegetation: It has actually long been well-known that plant expansion helps decrease erosion resulted in by flowing water. If girlfriend look in ~ hills without vegetation you"ll watch gullies dug the end by to run water. Land with plant cover slows the speed of the water flowing on it and thus helps to save soil indigenous eroding.


Water Equivalents (approximate)

The following equivalents present the relationship in between the volume and weight that water and also between the volume and also speed of flowing water.

Volume and also weight

One customs of rain fall on 1 acre of ground is same to around 27,154 gallons and also weighs about 113 tons.An customs of eye falling evenly on 1 acre of ground is identical to about 2,715 gallons of water. This figure, however, based upon the "rule-of-thumb" that 10 inch of eye is equal to 1 customs of water, can vary considerably, depending on whether the snow is heavy and wet, or powdery and also dry. Heavy, wet snow has a really high water content—4 or 5 customs of this sort of snow contains about 1 customs of water. Thus, an inch of very wet snow over an acre could amount to an ext than 5,400 gallons of water, while an inch of powdery snow can yield only around 1,300 gallons.One acre-foot that water (the quantity of water spanning 1 acre to a depth of 1 foot) amounts to 326,000 gallons or 43,560 cubic feet the water, and weighs 2.7 million pounds.One cubic mile of water amounts to 1.1 trillion gallons, 147.2 exchange rate cubic feet, or 3.38 million acre-feet, and weighs 9.2 trillion pounds (4.6 exchange rate tons).

See more: What Happened To The Cat Who Swallowed A Ball Of Yarn Math Answer Key

Rate of circulation (in a stream)

Water flowing at the steady rate of 1 gallon per minute is indistinguishable to: 1,440 gallons per day; 0.00223 cubic foot every second; 192.7 cubic feet per day; or 0.00442 acre-foot of water per day.Water flowing at the steady rate of 1 cubic foot per second is equivalent to: 449 gallons per minute; 646,000 gallons per day; 86,400 cubic feet every day; or 1.98 acre-feet of water every day.Water flowing at the steady price of 1 acre-foot every day is tantamount to: 226 gallons per minute; 326,000 gallons per day; 0.504 cubic foot per second; or 43, 560 cubic feet that water per day.Water flow at the steady rate of 1 cubic mile every day is tantamount to: 764.6 million gallons per minute; 1.1 trillion gallons per day; 1.7 million cubic feet every day; or 3.38 million acre-feet of water every day.