What Is the Wettest Place on Earth?

Mawsynram in northeastern India holds the World Meteorological Organization’s (WMO) official record for the highest average annual rainfall, with 11,872 millimeters (467.4 inches) recorded from 1941 to 1979. However, a rain gauge in western Colombia has measured an even higher long-term average.

The Puerto Lopez rain gauge, located in the municipality of Lopez de Micay in Colombia’s Cauca Department, recorded an annual average of 13,159 millimeters (518.1 inches) between 1960 and 2018. Researchers at the National University of Colombia identified it as the highest long-term average among the stations they evaluated. Their analysis used historical records from Colombia’s Institute of Hydrology, Meteorology and Environmental Studies (IDEAM).

The Colombian figure does not replace Mawsynram’s official WMO record. The two measurements come from different observation periods and have not been evaluated through the same international record system. Additional stations across Colombia have produced extraordinary totals, reinforcing evidence that the country’s Pacific coast is one of the planet’s most intensely rainy regions.

Western Colombia: A global precipitation hotspot

The Pacific lowlands of Colombia form a broad zone of extreme rainfall along the country’s western coast. A 2023 study in the Journal of Geophysical Research: Atmospheres identified western Colombia and the adjacent eastern equatorial Pacific as the rainiest region on Earth. Researchers documented long-term mean annual rainfall of 10,000 to 13,000 millimeters (393.7 to 511.8 inches) across parts of the region, with single-year totals exceeding 26,000 millimeters (1,023.6 inches) in some locations.

IDEAM identifies Colombia’s Pacific slope as the nation’s wettest zone, particularly in parts of Choco and Cauca. Annual rainfall exceeds 10,000 millimeters (393.7 inches) in several areas, with precipitation falling on more than 200 days a year.

The extreme rainfall results from the interaction between the Pacific Ocean and the Andes. The low-level Choco jet transports large amounts of moisture inland from the Pacific. When the humid airflow reaches the western slopes of the Andes, the mountains force it upward, helping trigger deep convection and heavy rainfall. The interaction of the Choco and Caribbean-Panama low-level jets further strengthens the atmospheric circulation that sustains the region’s exceptional precipitation.

The same conditions affect a broad stretch of the Pacific lowlands, where several stations have recorded exceptional rainfall totals. One of the strongest long-term records comes from the Puerto Lopez gauge.

Puerto Lopez yields Colombia’s strongest baseline

A 2020 study published in the Revista de la Academia Colombiana de Ciencias Exactas, Físicas y Naturales used historical IDEAM records from the Pacific lowlands to compare rainfall across several stations. The Puerto Lopez gauge had the highest average, at 13,159 millimeters (518.1 inches) per year from 1960 through 2018.

Nearby, the La Concha station recorded an annual average of 12,069 millimeters (475.2 inches) over the same timeframe.

Regional gauges further demonstrate the area’s extreme rainfall. Annual averages reached 10,946 millimeters (430.9 inches) at Tutunendo, Choco, and 10,536 millimeters (414.8 inches) at San Antonio de Yurumangui, Valle. In 2018, San Antonio de Yurumangui also set a dramatic single-year mark of 26,987 millimeters (1,062.5 inches).

The researchers stopped short of declaring an official world record. They described Puerto Lopez as “probably” the rainiest place on Earth, acknowledging the difficulty of comparing rainfall data from different countries and observation networks.

The 2018 total from San Antonio de Yurumangui also exceeds the WMO’s 12-month accumulation record for Cherrapunji, India, although the two measurements are not directly equivalent. The Colombian figure covers a calendar year, while the WMO record covers a specific consecutive 12-month period.

Data gaps and short records complicate historical claims

Earlier measurements at Puerto López yielded figures similar to the 2020 baseline. A 2013 analysis of IDEAM data calculated an annual average of 12,892.4 millimeters (507.6 inches) between April 1960 and Feb. 2012.

However, that series contained significant gaps, notably a long interruption from 1968 to 1979. Isolating the 31 complete monitoring years through 2011 produced an average of 13,466.3 millimeters (530.2 inches), though four months were missing after 1991.

Lloro in Choco presents similar comparative hurdles. Between 1952 and 1958, the Lloro La Granja station recorded an annual average of 12,717 millimeters (500.7 inches)—exceeding Mawsynram’s official benchmark—before closing after just seven years. A replacement gauge in Lloro averaged 8,240 millimeters (324.4 inches) per year from 1983 to 2018.

While this lower figure does not invalidate the 1950s data, the short operational window prevents direct comparison with multi-decade baselines. Consequently, the 2020 study excluded the historical Lloro gauge when selecting active stations for comparison.

Mawsynram retains official WMO recognition

Mawsynram’s status reflects the WMO’s formal system for recognizing meteorological extremes. The site lies in Meghalaya, where moisture-laden monsoon air from the Bay of Bengal encounters the Khasi Hills. The terrain forces the air upward, producing intense rainfall during the monsoon season.

Its official benchmark is 11,872 millimeters (467.4 inches) of average annual rainfall, based on observations from 1941 to 1979. The India Meteorological Department also continues to list Mawsynram as the world’s wettest location.

A rainfall measurement can exceed an established international record without automatically replacing it. The WMO record reflects a formal international system for evaluating meteorological extremes, while the Puerto Lopez figure comes from a peer-reviewed analysis of Colombian station data.

Single-year peaks vs. multi-decade averages

Average annual rainfall measures something different from the largest amount of rain recorded over 12 consecutive months.

The WMO lists nearby Cherrapunji, India, as the site of the greatest 12-month accumulation. A gauge there recorded 26,470 millimeters (1,042.1 inches) between Aug. 8, 1860, and July 7, 1861.

That total more than doubles Mawsynram’s long-term annual average and far exceeds Puerto Lopez’s baseline. It represents a 12-month accumulation, however, rather than the amount of rainfall expected at the location over many years.

So, what is the wettest place on Earth?

Determining the wettest place depends on the rainfall statistic being measured:

• Official WMO long-term average: Mawsynram, India — 11,872 millimeters (467.4 inches) per year over 38 years.
• Official WMO 12-month accumulation: Cherrapunji, India — 26,470 millimeters (1,042.1 inches) from 1860 to 1861.
• Highest long-term average reported in the Colombian station study: Puerto Lopez, Cauca — 13,159 millimeters (518.1 inches) per year over 58 years.

Mawsynram retains the formal WMO record, while Lopez de Micay gives Colombia a higher long-term average documented in peer-reviewed research. Which location is called the “wettest” depends on whether the comparison uses an internationally recognized record or a specific station’s long-term rainfall series.