ECMWF has substantially increased the amount of weather prediction data it makes available free of charge to Members of the World Meteorological Organization (WMO).
The provision of the data is part of the Centre’s obligations as a World Meteorological Centre (WMC). ECMWF became a WMC in June 2017.
The additional data enable a much more comprehensive view of atmospheric conditions as predicted by ECMWF than before, including near-surface weather conditions. This will help users to make better assessments of weather-related risks out to day 10.
Registered national meteorological and hydrological services (NMHSs) have been able to access the new data since 2 July 2018.
Additional fields are available for both probabilistic and deterministic forecasts. Users can now assess the probability of more than 1 mm and 5 mm precipitation in 24-hour periods out to 10 days ahead.
They can complement this with precipitation information based on the high-resolution forecast that is now available at 6-hour intervals. They can also access 6-day forecasts of 2-metre temperature and 10-metre wind.
All forecasts of weather variables are now provided at 6- or 12-hour time steps instead of 24-hour time steps.
The new products also include additional ocean wave forecast fields (peak wave period and mean zero-crossing wave period), with all wave forecast products provided at 3- or 6-hour time steps.
Together, these changes help to provide forecasters in the NMHSs of WMO Members with the information they need to carry out their operational activities.
The newly available data include near-surface weather variables such as 2-metre temperature, as shown in this 5-day forecast for 12 UTC on 21 July 2018.
Designation as a WMC
The World Meteorological Organization (WMO) Executive Council endorsed the designation of ECMWF as a WMC at its meeting in Geneva in May 2017.
ECMWF’s Council agreed to the provision of the new data at its 90th session in June 2017.
The change has now been implemented by adding the extra fields to ECMWF's Data Collection and Production Centre (DCPC) FTP server, from where registered NMHSs pull the data. The DCPC is part of the WMO Information System (WIS).
WIS aims to provide a single coordinated global infrastructure for the collection and sharing of information in support of all WMO and related international programmes.
In addition to giving WMO Members access to a range of products, WMCs provide relevant documentation and verification to demonstrate the quality of their forecasts. This is all done to assist WMO Members in their official duties at national level.
The extra data available to WMO Members include forecasts based on new probability thresholds for total precipitation. The chart shows the probability of total precipitation exceeding 5 mm over the last 24 hours of a five-day forecast for 12 UTC on 21 July 2018. The top image shows a section of the same chart.