Global Seasonal Climate Update

The WMO Global Seasonal Climate Update (GSCU), issued quarterly, summarizes the current status (monitoring) and the expected future behaviour (prediction) of the global seasonal climate focusing on the major general circulation features and large‐scale oceanic anomalies around the globe (e.g., El Niño/Southern Oscillation, North Atlantic Oscillation, Indian Ocean Dipole, etc.) and their potential impacts on the worldwide surface temperature and precipitation patterns.

The monitoring component of the GSCU is based on global climate monitoring information compiled by the National Oceanic and Atmospheric Administration (NOAA), United States of America, in collaboration with other global climate monitoring centres. The seasonal prediction component of the GSCU is based on an ensemble of global model forecasts produced by WMO-designated Global Producing Centres of Long-Range Forecasts (GPCs-LRF) spread around the world, whose products are consolidated by the WMO Lead Centre for Long-Range Forecast Multi-Model Ensemble (LC LRFMME), jointly coordinated by the Korea Meteorological Administration (KMA) and NOAA.


WMO has been issuing El Niño/La Niña Updates on a quasi-regular basis over the past 25 years, providing useful real-time information based on expert assessments underpinned by WMO’s role as the UN System’s authoritative voice on weather, climate and water. While these have been well‐received worldwide due to the significant implications of El Niño/La Niña occurrence for regional climate impacts, there has been a persistent and widely expressed need to expand on these products to include more comprehensive information on the seasonal climate, particularly in terms of precipitation and temperature patterns. To complement the WMO El Niño/La Niña Updates, the Sixteenth World Meteorological Congress decided to develop a Global Seasonal Climate Update (GSCU). The GSCU provides information on regional climate anomalies associated with El Niño, La Niña and other climate drivers." The GSCU provides the international community with a global‐scale expert assessment of the ongoing and upcoming seasonal climate along with information on robustness of the available forecast signals.

The GSCU has been designed to be used primarily by WMO Regional Climate Centres (RCCs), Regional Climate Outlook Forums (RCOFs) and National Meteorological and Hydrological Services (NMHSs) as an important global input into their operational activities to elaborate on the ongoing and upcoming seasonal climate on regional and national scales. Additionally, it also caters to the global user needs such as those of the United Nations agencies, humanitarian agencies, the Early Warning Early Action Reports of the Inter Agency Standing Committee (IASC), etc. The Updates are regularly issued a few days ahead of each of the standard seasons (DJF/MAM/JJA/SON). In addition, a simplified version of the GSCU is also being provided every month as an interim update. The coordinators of WMO LC LRFMME, NOAA and KMA have integrated the regular production of GSCU into their operational schedule and have made concerted efforts to ensure its timely provision and dissemination.

The GSCU has a long history over more than a  decade in its making, involving consultations with a wide range of stakeholders,  a trial run, a peer-review process and a pre-operational phase under the  guidance of the World Meteorological Congress, WMO Executive Council and WMO  Technical Commissions.  The GSCU is  currently guided by the WMO Services Commission and Infrastructure Commission.

For more information: GSCU Evolution: WMO Cg/EC/CClDecisions (key development milestones).

Past releases

Since May 2019 the GSCU is being produced on a regular basis as a pre-operational product and disseminated widely to WMO Members, as well as regional and international partners and United Nations organizations. The GSCU current and past releases are accessible in real-time through a dedicated web page of LC-LRFMME website