How much rainfall does Houston receive each year?
Because rainfall is highly variable over short and long distances, the answer could be quite different.
When people refer to rainfall totals in Houston (TX), the data presented is typically from the official observation site, currently located at Houston’s Intercontinental Airport (KIAH) located about 17 miles north of Downtown Houston. KIAH has been the official site since the airport’s opening in 1969. The National Weather Service Forecast Office for the Houston/Galveston area offers this summary:
“The official observation site for the city of Houston was moved quite a few times during its long history. The city office was located in downtown Houston and observations began in July 1881. Regrettably, weather records prior to 1889 are not available. However, a relatively complete set of daily temperature and rainfall data is available dating back to 1892 with some temperature and rainfall records dating back to 1889. The city office remained in downtown Houston from 1881 through May 1969. Intercontinental Airport opened in June 1969 and the official observation site was moved to the airport upon its opening. The official observation site has been located at Intercontinental Airport ever since. Although the downtown office was the official observation site for almost eighty years, the office moved quite a few times around downtown Houston. Below is a list of locations and dates of the official observation site.
- Cotton Station (July 1881 – September 1909)
- Stewart Building at Preston and Fannin (September 1909 – February 1926)
- Shell Building at Texas and Fannin (March 1926 – August 1938)
- Federal Building at Franklin and Fannin (August 1938 – May 1969)
- Intercontinental Airport (June 1969 – Present)”
Here is a tabular view of the annual rainfall amount reported from KIAH since 1969:
Note: the data in 1969 is only a partial year’s worth of data and is not included in any calculations.
Here is a graph of the same data:
Source: Data obtained from the Midwestern Regional Climate Center, cli-MATE (MRCC Application Tools Environment, on http://mrcc.isws.illinois.edu/CLIMATE/welcome.jsp/)
So, back to the original question.
How much rainfall does Houston get each year? Well, going by the official observation site located at KIAH, right around 50″ of rain.