# The Gu and Deyr rains, 1950 to 2023: every rainy season in numbers > Rain in Somalia's Gu and Deyr seasons for every year from 1950 to 2023, compared with normal, with the dry seasons and floods that shaped people's lives. Source page: https://calankii.com/en/data/gu-and-deyr-rains-1950-2023/ Last checked: 2026-11-12 Publisher: Calankii (https://calankii.com) ## Where these numbers come from These figures are from **ERA5**, the climate reanalysis of the European Centre for Medium-Range Weather Forecasts. A reanalysis combines weather stations, satellites and a weather model to rebuild the rain for every month since 1950, even where there are no stations. We took Somalia's national monthly averages from the World Bank's Climate Change Knowledge Portal and added up the months of each season ([World Bank Climate Change Knowledge Portal, ERA5](https://climateknowledgeportal.worldbank.org/country/somalia/era5-historical); [ECMWF, ERA5](https://www.ecmwf.int/en/forecasts/dataset/ecmwf-reanalysis-v5)). "Normal" here means the 1991 to 2020 average. The full table for every year is in the data file `somalia-gu-deyr-rainfall-1950-2023.csv` on this page. **Why ERA5 and not station data.** Somalia has had few working weather stations since 1991. The station-based CRU dataset, which the [yearly rainfall page](/en/data/rainfall-and-temperature-1901-2023/) uses for the long view back to 1901, shows the Gu of 2022 as wet. ERA5 shows it as the driest Gu since 1950, which matches what farmers, herders and the World Meteorological Organization reported ([WMO, August 2022](https://wmo.int/media/news/greater-horn-of-africa-faces-5th-failed-rainy-season)). This site uses ERA5 for single seasons for that reason. ## A normal year Average rain by month, 1991 to 2020, ERA5 (same source): - Jiilaal: January 6 mm, February 3 mm, March 12 mm - **Gu:** April 64 mm, May 51 mm, June 8 mm. Season total about 123 mm. - Xagaa: July 7 mm, August 7 mm, September 10 mm - **[Deyr](/en/economy/pastoralism-in-somalia/):** October 58 mm, November 54 mm, December 17 mm. Season total about 130 mm. The year totals about 297 mm, and the two seasons bring more than four fifths of it. ## The driest seasons since 1950 Rain as a share of the normal season (same source): - **Deyr 2010: 11 percent.** It was followed by a poor Gu in 2011 (84 percent). The UN declared famine in parts of southern Somalia in July 2011 ([2011 East Africa drought, Wikipedia](https://en.wikipedia.org/wiki/2011_East_Africa_drought)). - **Deyr 2021: 31 percent**, then **Gu 2022: 44 percent** and **Deyr 2022: 47 percent**. Three failed seasons in a row, in the Horn of Africa's worst drought in more than 40 years ([WMO, August 2022](https://wmo.int/media/news/greater-horn-of-africa-faces-5th-failed-rainy-season)). - **Deyr 1974: 34 percent** and **Deyr 1975: 38 percent.** This was the drought Somalis call **Abaartii Dabadheer**, "the long-tailed drought". The government declared a state of emergency in November 1974 ([Hiiraan Online, 2014](https://hiiraan.com/op4/2014/Oct/56713/the_approaching_risk_of_another_famine_in_somalia.aspx); [Yeheb](https://www.yeheb.org/drought-context-vulnerability-solutions-muna-ismail/)). - **Deyr 2016: 44 percent**, followed by a below-normal Gu in 2017 (78 percent). - Other dry Gu seasons: 1969 (59 percent), 1999 (61 percent), 1992 (68 percent), 2004 (68 percent) and 2014 (70 percent). ## The wettest seasons - **Deyr 1997: 318 percent of normal**, the wettest season in the record. - **Deyr 2023: 199 percent**, in an El Niño year, straight after the long drought. - Deyr 1951 (201 percent), Deyr 2004 (181 percent) and Deyr 2019 (181 percent). - Gu 1953 (234 percent), Gu 1951 (213 percent) and Gu 2018 (166 percent). ## What the record shows - **The Deyr swings more than the Gu.** Since 1950 the Deyr has ranged from 11 to 318 percent of normal; the Gu from 44 to 234 percent. - **Bad Deyr seasons come before most hunger crises.** The Deyr of 1974, 2010, 2016 and 2021 were each followed by a hard year. The Deyr rain feeds the pasture and water that herders depend on through the Jiilaal dry season, and the Gu harvest comes months later. - **Wet can follow dry.** In 2023 the wettest Deyr since 1997 came straight after three seasons in a row with well below normal rain. A national average hides big differences between regions. The farming regions between the [Juba](/en/economy/farming-and-harvests/) and Shabelle rivers depend most on the Gu harvest; the pastoral north depends on both seasons for pasture. For seasonal outlooks and hunger warnings by region, see FEWS NET and [FSNAU](/en/institutions/fao-somalia/) ([FEWS NET, Somalia](https://fews.net/east-africa/somalia); [FAO FSNAU](https://fsnau.org/)). ## Related - [Rain by region, 1991 to 2023](/en/data/rain-by-region-1991-2023/) - [Rainfall and temperature in Somalia since 1901](/en/data/rainfall-and-temperature-1901-2023/) - [Internal displacement](/en/society/internal-displacement/) - [Prices and inflation](/en/economy/prices-and-inflation/) --- I want to help with this: email hello@calankii.com. Fix this page: email hello@calankii.com with the page link and your source.