The Challenge (UEF2016)

The ENS Meteogram

Ensembles of weather forecasts enable us to quantify uncertainty consistently with our knowledge of the initial conditions and model capability. Visualisation of the large amount of data produced by ensemble forecasting systems is important to help translating the quantified uncertainty described by the ensemble system into information on confidence to be provided to end-users.

Visualising the uncertainty of a forecast is therefore of primary importance and ECMWF developed the Ensemble Meteogram which is primarily a probabilistic representation, for a given location, of forecasts from an ensemble forecasting system. The ENS currently comprises 50 perturbed members, each starting from slightly different initial conditions, and an unperturbed control forecast. A more detailed description of the ENS meteogram is available.

The Challenge

The ENS Meteogram is a very popular product among ECMWF data users. It summarises graphically the whole ensemble distribution at a specific location for a set of parameters. We are seeking ways to improve it and these are our three challenges:

Challenge 1: Visualising the forecast distribution

Innovative ways of displaying the time evolution ensemble distribution forecast. This could be for example a violin box plot or a wind rose.

Figure 1: Examples of visualisation

Challenge 2: Adding components

Increased functionalities of the ENS Meteogram. This could be for example possibility of setting an alert threshold which triggers an action like sending a warning message.

ENS meteogram new functionalities

Figure 2: Example of increased functionality

Challenge 3: Customising

Designing a user interface to allow more customisation. This could be for example an application through which a user can interactively select parameters, visualisation and layout, that is produce a display that is tailored to her/his needs.

ENS meteogram new features

Figure 3: Example of user interface

Your submission should contain a graphical display of your proposed idea and a brief description of the rationale behind it. Your submission should not exceed 1000 words. We provide a set of data (15 day forecast at a specific location for temperature, wind, cloud cover, precipitation accumulated over 24 hours) which you can use to illustrate your idea (please download the data from here). Please do not limit your imagination to the data provided, that is if you think other parameters or combination of parameters needs to be displayed, use synthetic data. Submissions can be by individuals or teams.

Submissions and voting

Applicants are requested to submit their ideas/projects for one of the challenges by 15 December 2016 at the following link:

The board of judges will evaluate the ideas/projects and shortlist the two best submissions which will be presented at the ECMWF annual user meeting (UEF) in 2017. The decision on the best two ideas will be communicated no later than the 31st January 2017.

For any queries, please send an email to:

Judging criteria

The key criteria used to evaluate the submissions are:  

  • potential for innovation
  • relevance / usefulness
  • technical merit
  • design / user experience / polish
  • "wow" factor

Board of judges

Dr Erik Andersson

Mr. Jose Luis Casado

Dr Anna Ghelli

Ms Nicole Girardot

Ms Sylvie Lamy-Thepaut

The Small Print

The ECMWF ENS Meteogram Challenge (hereafter referred to as “The Challenge”) is promoted by The European Center for Medium Range Weather Forecasts (ECMWF), Shinfield Park, RG2 9AX, Reading, UK. These terms and conditions govern your participation to The Challenge. By submitting your entry, you agree to the following:

  1. To enter: You must be at least 18 years of age or older at the time of entry. Participation is open to anybody who uses ECMWF data. Details on how to enter The Challenge are published on the ECMWF website. The Participant and ECMWF are ‘Parties’ to this agreement.
  2. Purpose: The purpose of The Challenge is to encourage Participants to use their knowledge and creativity to generate awesome ideas and change the world.
  3. Intellectual Property Rights: All your original work is and will remain yours. You are free to use the results of your submission for any purposes. You will not hold ECMWF responsible for any other participant's or third party's use of the results of your own submission.
  4. Grant of rights: Your entry and the ideas or concepts submitted by you for The Challenge may be used and reproduced by ECMWF (and its assignees) in perpetuity for any purpose whatsoever and you hereby grant ECMWF the perpetual sub-licensable right to do so exclusively, royalty-free and without limitation.
  5. Your submission to The Challenge must only concern your own original work and must not, so far as you are aware, infringe the intellectual property or any other legal or moral rights of any third party, and must not violate applicable law or refer to or portray ECMWF in a disparaging or negative manner. Participants may flag up and define pre-existing IPR if they wish. It is recommended that such pre-existing IPR be identified in a written document before disclosure at submission time.
  6. You acknowledge and agree that a third party may submit similar ideas or concepts for The Challenge. You also acknowledge and agree that ECMWF, as an international organisation with a strong reputation for innovation, may be working on similar ideas independently whether now or in the future. You agree not to make any claims or demands of any nature against ECMWF in relation to your participation in The Challenge.
  7. Winner selection: A panel of  judges will shortlist two ideas which will be published on the ECMWF (and other related) websites and will be presented at the ECMWF user meeting, UEF, in 2017. The decisions of ECMWF and the judges are final and binding, and may not be appealed.
  8. Name and likeness: ECMWF may take photographs and film (audio and video) of the winners  to be used for publicity and/or promotional purposes. You can opt out by letting us know by email to
  9. In the event of a dispute arising in connection with The Challenge or these Terms and Conditions, the Parties shall attempt to settle their differences in an amicable manner. In the event that any dispute cannot be settled, it shall be finally settled under the rules of conciliation and arbitration of the International Chamber of Commerce by one arbitrator appointed in accordance with such rules sitting in England and chosen by agreement. In accordance with sections 45 and 69 of the Arbitrations Act 1996, the right of appeal by either party to the High Court on a question of law arising in the course of any arbitral proceedings or out of an award made in any arbitral proceedings in hereby agreed to be excluded.