Saint-Jean-de-Védas (French pronunciation: [sɛ̃ ʒɑ̃ də vedas]; Languedocien: Sant Joan de Vedats) is a commune in the Hérault department in the Occitanie region in southern France.

Located southwest of Montpellier, the commune is composed of a series of increasingly steep hills towards the southwest and the Gardiole massif. It is traversed by the Rieucoulon River along its boundary with Montpellier and by the Mosson River to the west and south.

The commune borders Montpellier to the north and east, Juvignac and Lavérune to the northwest, Fabrègues to the southwest, and Villeneuve-lès-Maguelone to the southeast, and Lattes to the east.

In 2010, the climate of the commune is classified as a frank Mediterranean climate, according to a study based on a dataset covering the 1971-2000 period. In 2020, Météo-France published a typology of climates in mainland France in which the commune is exposed to a Mediterranean climate and is part of the Provence, Languedoc-Roussillon climatic region, characterized by low rainfall in summer, very good sunshine (2,600 h/year), a hot summer 21.5 °C (71 °F), very dry air in summer, dry conditions in all seasons, strong winds (with a frequency of 40 to 50% for winds > 5 m/s), and little fog.

For the 1971-2000 period, the average annual temperature was 14.4 °C (58 °F) with an annual atmospheric temperature of 16.3 °C (61 °F). The average annual total rainfall during this period was 657 mm, with 5.8 days of precipitation in January and 2.7 days in July. For the subsequent period of 1991 to 2020, the average annual temperature observed at the nearest weather station, located in the commune of Saint-André-de-Sangonis, 6 kilometres (4 mi) away as the crow flies, is 15.4 °C (60 °F), and the average annual total rainfall is 591.6 mm.

For the future, climate parameters for the commune projected for 2050, based on different greenhouse gas emission scenarios, can be consulted on a dedicated website published by Météo-France in November 2022.

As of January 1, 2024, Saint-Jean-de-Védas is classified as a ‘grand centre urbain’ (major urban center) according to the new seven-level commune density grid established by Insee in 2022. It is part of the Montpellier urban unit, an intra-departmental agglomeration comprising 22 communes, of which Saint-Jean-de-Védas is a suburban commune. Additionally, Saint-Jean-de-Védas belongs to the Montpellier attraction area, where it is designated as a primary hub city. This area, encompassing 161 communes, falls under the category of areas with 700,000 inhabitants or more (excluding Paris).

The land use in the commune, as recorded in the European biophysical land use database, Corine Land Cover (CLC), is characterized by a high proportion of artificial areas, accounting for 51.4% in 2018, up from 33.9% in 1990. The detailed distribution in 2018 was as follows: urban areas (30.2%), heterogeneous agricultural areas (26.5%), industrial or commercial zones and communication networks (21.2%), shrub and/or herbaceous vegetation environments (18.5%), grasslands (1.9%), forests (1.3%), and arable land (0.5%). Changes in the commune’s land use and infrastructure can be observed on various cartographic representations of the area: the Cassini map (18th century), the military topographic map (1820–1866), and IGN maps or aerial photographs from 1950 to the present day.

Changes in the number of inhabitants have been documented through population censuses conducted in the commune since 1793. For communes with over 10,000 inhabitants, censuses are conducted annually via a survey based on a sampling of addresses representing 8% of the dwellings. This differs from other communes, where a full census is conducted every five years.

In 2021, the commune had a population of 12,570; reflecting an increase of +38.6 since 2015 (Hérault: +7.29%, France excluding Mayotte: +1.84%).

Historical population

Year Pop. ±% p.a. 1793 441 —     1800 483 +1.31% 1806 497 +0.48% 1821 483 −0.19% 1831 562 +1.53% 1836 593 +1.08% 1841 628 +1.15% 1846 662 +1.06% 1851 703 +1.21% 1856 650 −1.56% 1861 655 +0.15% 1866 746 +2.64% 1872 824 +1.67% 1876 864 +1.19% 1881 674 −4.85% 1886 759 +2.40% 1891 788 +0.75% 1896 883 +2.30% 1901 859 −0.55%	Year Pop. ±% p.a. 1906 845 −0.33% 1911 858 +0.31% 1921 876 +0.21% 1926 910 +0.76% 1931 936 +0.57% 1936 956 +0.42% 1946 986 +0.31% 1954 1,149 +1.93% 1962 1,772 +5.56% 1968 2,086 +2.76% 1975 3,529 +7.80% 1982 4,284 +2.81% 1990 5,390 +2.91% 1999 8,056 +4.57% 2006 8,585 +0.91% 2011 8,632 +0.11% 2016 9,539 +2.02% 2021 12,570 +5.67%
Source: Ldh/EHESS/Cassini until 1999, and INSEE since 2006.

• Communes of the Hérault department