Category : Meteorology

Alternative weather models [Update]

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[Update 29 July 2022]

For several years, forecast files in GRIB format have been widely used in meteorological applications.. The majority of forecast models have been made freely available by meteorological services, all countries included. Apps like XyGrib, LuckGrib, SailGrib, Weather4D and others, offer a selection of atmospheric and oceanic models, up to 60 Weather Models, Waves and currents for Weather4D, more than thirty models with LuckGrib, in example. But there are always others that can usefully complement the standard offerings of these applications. Read more …

Predict storms with Weather4D

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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 …

Reading : “Clouds and other meteors” Météo-France

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In an article updated in August 2020 (¹), I described nautical works in digital format that can be usefully saved on iPad in the Apple Books application. Among them, I mentioned the Météo-France books available in PDF format for free download from their documentary portal.

In the "Courses and Manuals" section of this site, a new book can be downloaded, Published in 2020, entitled " Meteorological Observations and Measurements – Volume 1 / Clouds and other meteors ”, A wealth of information about clouds, and all associated weather phenomena, which are called "meteors" (²). Read more …

You said « Medicane » ?

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Many sailors who cross the "Big Blue" have known for ages that, if the navigation is relatively easy, the weather represents a particularly difficult constraint to deal. Indeed, if the coasts are mostly clean and the dangers very localized, if the tides are almost insignificant, if the currents are to be considered only in well defined areas, the major difficulty comes from a capricious meteorology, difficult to forecast, which can represent a real danger by its changing moods, sudden, even rough. Read more …

New major evolution of the GFS model

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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

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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 …

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

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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.

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

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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 Member States and 12 Associated states. It employs nearly 350 persons, and its supercomputer equipment is one of the largest in Europe. For the past fifteen years or so, ECMWF forecasts tend to be among the most accurate in the world, according to verification data from the World Meteorological Organization (WMO). ECMWF is currently headed by French meteorologist Florence Rabier, who worked at the local meteorological office of Météo-France.

But, since the advent of Brexit, The situation has changed. The United Kingdom is no longer part of the EU, ECMWF must move to a European country, and this could lead to, For weather data users, consequences rather… Positive ! Read more …

Receive facsimile weather maps with an iPad [Update]

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Un récepteur BLU plaisance

An SSB receiver for leasure boating

HF Weather Fax to Black Cat Systems is an application allowing you to decode facsimile weather maps on an iPad, an iPhone or Android device. The analysis and forecast maps are provided by radio stations around the World. Broadcast on shortwave, they can easily be received by BLU receivers as found in boating catalogs.
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