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Predict storms with Weather4D

Posted on14 July 20213 August 2024

In Weather4D (all versions) most weather models provide a data called CAPE.

Convective Available Potential Energy, in French : Energie potentielle de convection disponible. Behind this obscure acronym hides a powerful storm forecasting tool. CAPE is measured in Joules per kilogram of air (J/Kg) and defines the vertical buoyancy energy of a hot air particle in a colder atmosphere. In other words, vertical acceleration of the air particle will be directly related to this energy measurement. Read more …

New major evolution of the GFS model

Posted on25 th 20218 December 2023

NOAA (¹) annouced on 22 March a major upgrade to its weather forecasting model GFS.

For the first time, the Global Forecasting System (GFS), NOAA's flagship weather forecast model (¹) will be coupled with the global wave model Wave Watch III (WW3), produced by the CMNF (Fleet Numerical Meteorology and Oceanography Center), which will extend the current forecast of waves from 7 down to 16 days and improve the prediction of ocean waves forced by the atmosphere. Read more …

Sea state : interpret wave patterns

Posted on18 th 202120 July 2024One comment

In Weather4D, as generally in other applications, sea state forecasts are described by ocean models. The most used is the model WW3 (Wave Watch III), published by FNMOC (Fleet Numerical Meteorology and Oceanography Center) of the US Navy, with a global model due to 7 days and resolution 1° (60NM), and a Europe model to 3 days and resolution 0.2° (12NM). Météo-France publish the models MFAUM (Wave Assimilated Model) coupled with the ARPEGE and AROME weather models with three resolutions : Global at 0.5° (30NM), Europe at 0.1° (6NM), France at 0.025° (1,5NM) with variable deadlines (¹). Read more …

Routing : from game to reality (continue)

Posted on12 November 202015 August 2024One comment

Friday 13 November will not be a lucky day for the Vendée Globe skippers 2020 (¹). Ils vont devoir négocier la rencontre avec la tempête tropicale « Theta » qui croise leur parcours avec des vents moyens pouvant atteindre les 40 nœuds et de puissantes rafales. Surtout la mer sera à craindre car, fortement croisées au passage du centre dépressionnaire, les vagues pourront dépasser les 6 mètres et déferler de façon chaotique. Read more …

Routing : from game to reality

Posted on10 November 20206 th 20245 comments

On the second day of racing of this Vendée Globe 2020, we can say that the weather conditions that the skippers will experience on the descent towards the Doldrums will be particularly tough. Après un départ par un temps de demoiselle, un premier front froid peu actif passé sans encombre, les solitaires vont traverser un deuxième front beaucoup plus violent dans la nuit et la matinée de mardi à mercredi, pour le groupe parti à l’Ouest, et dans la soirée pour le groupe passé entre le DST (¹) et la Gallice.

Mais ces conditions à venir sont bien différentes pour les joueurs de Virtual Regatta et pour les marins… Read more …

ECMWF weather data soon open to public [2rd part]

Posted on1 October 202022 January 20252 comments

Source : The Parliament Mag par Umberto Modigliani, ECMWF Deputy Director of Forecasts, responsible, with the department director, continuous production of forecasts and relations with users.

Early October, the European Centre for Medium-Range Weather Forecasts (ECMWF) will take a big step forward by making hundreds of its forecast maps available to everyone free of charge.
The changes are part of a broader European initiative to make public sector data free and open, encourage innovation and support a thriving data-driven digital economy.

Thus far, full access to these forecast maps was restricted to the national meteorological and hydrological services of the Member States and the ECMWF Cooperating States, to members of the World Meteorological Organization and commercial customers. Access was subject to a series of customized licenses and high royalties.

ECMWF weather data soon open to public [1st part]

Posted on1 October 20203 January 2022

Created in 1975 at the initiative of members of the European Union, the European Center for Medium-Range Weather Forecast is an independent intergovernmental organization whose headquarters, until this day, is located in Reading, England. ECMWF is funded by 22 états membres et 12 états associés. Il emploie près de 350 personnes, et son équipement de supercalculateurs est l’un des plus importants en Europe. Depuis une quinzaine d’années, les prévisions du CEPMMT tendent à être parmi les plus précises au monde, selon les données de vérification de l’Organisation Météorologique Mondiale (WMO). Le CEPMMT est actuellement dirigé par la météorologiste française Florence Rabier, qui a travaillé au bureau météorologique local de Météo-France.

But, depuis l’avènement du Brexit, la situation a changé. Le Royaume-Uni ne faisant plus partie de l’UE, le CEPMMT doit déménager vers un pays européen, et cela pourrait engendrer, pour les utilisateurs de données météo, des conséquences plutôt… positives ! Read more …

The weather models war will take place [Update]

Posted on13 June 20196 th 20244 comments

I relayed in December 2018 an excellent issue published on the blog of our friends at Geogarage, who make a permanent duty of a press review of the best foreign articles concerning cartography, meteorology, and more generally all subjects related to maritime navigation. Here is a translation freely adapted and commented on in French. Read more …

Iridium Mail & Web app : GRIB weather files on iPhone and iPad in open sea [Update-2]

Posted on2 June 201711 th 202415 comments

[Update 15 February 2019] The recent update of the application Iridium Mail & Web app gives me the opportunity to refresh this post originally written in December 2011.

The Wi-Fi Gateway Optimizer from RedPort allows owners of a mobile satellite phone to make requests and receive GRIB weather files from an iPad or iPhone on the high seas, into the wild, anywhere on the world.

After implementing and testing this solution On a long journey, It proved to be perfectly operational. However, it is limited to the receipt of the forecasts of the GFS weather model worldwide, and the wave pattern WW3, obtained by the American server's autoresponder Saildocs.

Weather4D 2.0.11 A bunch of new features and improvements

Posted on21 th 20166 th 202417 comments

Delivered in AppStore this morning after two weeks of revisions and contre-revisions of Apple services, Always more picky, The new version is finally available. On the menu and in bulk : AIS via internet with AISHub, direct access to Geogarage and cache memory chart management, new model of GRIB weather forecast from Meteo-France AROME HD for inshore races, mode plein-écran, advanced distance calculations, the most visible. Under the hood also a lot of optimization for routing and power consumption. Revue de détail à suivre… Read more …