Regional Activities in Hydrology
Decisions concerning the implementation of the regional activities are taken by the WMO Regional Associations at their four-yearly meetings. The six Regional Associations of WMO have each established a working group on hydrology (WGH), and a Regional Hydrological Adviser (RHA) represents his/her entire Region and authoritatively represents the regional hydrologic concerns, problems or expectations, particularly as based on regional consultations. At the national level, the Hydrological Adviser (HA) is the ambassador of WMO hydrology.

RA I - Africa
Current RA I Hydrological and Water Coordination Panel
- Terms of reference for Hydrological and Water Coordination Panel (Resolution 3.2/1 (RA I-18) 2021) en - fr
- Regional progress on Hydrological and Water Resources Services components (Resolution 4.1/3 (RA I-18(II)) 2021) en - fr
Hybrid Forums
- Second Hydrological And Water Coordination Panel Region I - Africa, 5-7 April 2022, Yaounde, Cameroon
Virtual Forums
- Third Hydrological Advisors Forum and HWCP Region I- Africa, 02 August 2022
- Third Hydrological And Water Coordination Panel Region I - Africa, 16 December 2022
- Second Hydrological Advisors Forum Region I - Africa, 29 January 2021
- First Hydrological Advisors Forum Region I - Africa, 16 June 2020
Former Working Group on Hydrology
- WMO RAI Working Group on Hydrology
- Report of the eleventh session of the WMO RA I Working Group on Hydrology (WGH) 16 – 20 November 2015, Accra, Ghana

RA II - Asia
Current RA II Working structure in hydrology and Water Resources
- Terms of reference for Coordination Panel on Hydrology and Water Resources (Resolution 2 (RA II-17) 2021) ar - ch - en - ru
- Terms of reference for Substructure of Working Groups in RA II en
- Regional priorities for hydrology and water resources in RA II (Resolution 6 (RA II-17) 2021) ar - ch - en - ru
- RA II Operating Plan (Resolution 10 (RAII-17) 2021) ar - ch - en - ru
RA II Coordination Panel on Hydrology and Water Resources (RA II CP-Hydrology)
- First face-to-face meeting (hybrid format), 31 October and 1 November 2022
- First virtual meeting, 29 September 2022
Virtual Forums
- Fifth Hydrological Advisers Forum Region II - Asia, 15 December 2022
- Fourth Hydrological Advisers Forum Region II - Asia, 29 March 2022
- Third Hydrological Advisers Forum Region II - Asia, 30 November 2021
- Second Hydrological Advisers Forum Region II - Asia, 26 March 2021
- First Hydrological Advisers Forum Region II - Asia, 11 September 2020
Former Working Group on Hydrology
- 2019 Meeting of RA II WGHS (7-9 October 2019)
- 2018 Meeting of RA II WGHS (26-28 November 2018)
- First Meeting of RA II WGHS (17-19 October 2017)
- Third Meeting of RA II WGHS (25-27 October 2016)
- Second Meeting of RA II WGHS (14-16 April 2015)
- First Meeting of RA II WGHS (30 September - 2 October 2014)
- Report of the RA II WGHS Session, 29-30 March 2007, Beijng, China

RA III - South America
Current RA III Working Group on Hydrology and Water Resources
- First meeting of the RA III Working Group on Hydrology and Water Resources, 31 May 2022 eng - esp
- Terms of reference (Resolution 1 (RA III-18) 2020) eng - esp
- Regional hydrological priorities (Resolution 4 (RA III-18) 2020) eng - esp
- Composition and information about the group
Current Developments
- WMO Hydrological Observing System in the La Plata Basin (WHOS-Plata) Portal
- Hydrometeorological Forecasting and Early Warnings System in the La Plata Basin (PROHMSAT-Plata)
- Enhancing Adaptive Capacity of Andean Communities through Climate Services (ENANDES)
- North West South America Flash Flood Guidance System (NWSAFFGS)
Virtual Forums
- RA III Virtual Hydrology Forum
- Hydrological Advisers Forums
- 6th Hydrological Advisers Forum Region III, 14 January, 2023
- 5th Hydrological Advisers Forum Region III, 27 July, 2022
- 4th Hydrological Advisers Forum Region III, 17 February 2022
- 3rd Hydrological Advisers Forum Region III, 26 August 2021
- 2nd Hydrological Advisers Forum Region III, 25 March 2021
- 1st Hydrological Advisers Forum Region III, 8 October 2020
Former Working Group on Hydrology
- Segunda Reunión Conjunta de los Grupos de Trabajo de la AR-III: Hidrología (GT-HRH), Clima (GT-CL) e Infraestructura y Desarrollo Tecnológico (GT-IDT), 4-6 Octubre 2017, Asunción, Paraguay
- Second joint meeting of the RA III Working Groups on Hydrology (WG-HWR), Climate (WG-CL) and Infrastructure and Technological Development (WG-ITD), 4-6 October 2017, Asunción, Paraguay
- Informe Final GT-HRH Décimo cuarta reunión, 4-6 Octubre 2017, Asunción, Paraguay
- Informe Final Décimo tercera reunión, Grupo de Trabajo sobre Hidrología y Recursos Hídricos, (octubre 2015)

RA IV - North America, Central America, Caribbean
Current RA IV Hydrological and Water Coordination Panel
- Second meeting of the RA IV Hydrological and Water Coordination Panel, 5 April 2022
- First meeting of the RA IV Hydrological and Water Coordination Panel, 11 March 2022
- Terms of reference (Resolution 5 (RA IV-18) 2020) eng - esp
- Hydrology and Water Resources (Resolution 3 (RA IV-18) 2021) eng - esp
- Composition and information about the Panel
- Groups working in coordination with the Panel:
Documents
- Road map for Hydrology and Water in RA IV (May 2021)
Current developments
- Development of the RA IV Action plan in Hydrology (in preparation)
- Synergies between hydrometeorological systems in the Dominican Republic
- Central America Flash Flood Guidance System (CAFFGS)
Virtual Forums
- RA IV Virtual Hydrology Forum
- Hydrological Advisers Forums
- 6th Hydrological Advisers Forum RA IV, 2 December, 2022
- 5th Hydrological Advisers Forum RA IV, 8 July, 2022
- 4th Hydrological Advisers Forum RA IV, 12 August 2021
- 3rd Hydrological Advisers Forum RA IV, 26 April 2021
- Second Hydrological Advisers Forum RA IV, 5 October 2020
- First Hydrological Advisers Forum RA IV, 20 July 2020
Former Working Group on Hydrology
- Report Eleventh Meeting of RA IV WGH, 23-25 January 2018, Kingston, Jamaica
- Report Tenth Meeting of RA IV WGH, 23 February 2015, San Salvador, El Salvador
- Report Ninth Session of RA IV WGH, 4-7 December 2006, San Salvador, El Salvador

RA V - South-west Pacific
Current RA V Working Group on Hydrology and Water Resources
- Terms of reference for Working Group on Hydrology and Water Resources (Resolution 3.1/1 (RA V-18) 2021) en - fr
- Regional progress on Hydrological and Water Resources components in RA V (Resolution 4.1/1 (RA V-18) 2021) en - fr
Virtual Forums
- Fourth Hydrological Advisers Forum Region V - South-west Pacific, 7 April 2022
- Third Hydrological Advisers Forum Region V - South-west Pacific, 2 December 2021
- Second Hydrological Advisers Forum Region V - South-west Pacific, 18 March 2021
- First Hydrological Advisers Forum Region V - South-west Pacific, 15 October 2020
- RA V Virtual Hydrology Forum
Former Working Group on Hydrology
- Report Ninth Session RA V WGH , 9-13 November 2015, Brisbane, Australia Final report
- Report Eighth Session RA V WGH , 25-29 November 2013, Christchurch, New Zealand
- Report Seventh Session RA V WGH, 14-18 December 2009, Bandung, Indonesia Final report
- Report Sixth Session RA V WGH, 17-21 October 2005, Nadi, Fiji
- Report meeting of experts on Hydrological needs of small islands, 4-6 October 1999, Nadi, Fiji

RA VI - Europe
Current RA VI Regional Hydrological Assembly
- Terms of reference for Regional Hydrological Assembly (Resolution 3.2/1 (RA VI-18) 2021) ar - en - fr - ru
Virtual Forums
- Third Hydrological Adviser Forum Region VI Europe, 28 June 2022
- Second Hydrological Advisers Forum Region VI - Europe, 27 April 2021
- First Hydrological Advisers Forum Region VI - Europe, 15 September 2020