Trafalgar Hit for the flagship of European meteorology, despite Brexit and contrary to what had been planned (¹), the European Center for Medium-Range Weather Forecast will stay in England ! Even better, a new headquarter for ECMWF to be fully funded by the UK government through the Department for Business, Energy and Industrial Strategy. Proof that the British have gone all out to keep this European scientific center in Reading (²). Read more …
Label : weather
Are GRIB files consistently optimistic ?
I've been asked this question regularly, but until now I've never wanted to give my opinion on the subject publicly, so as not to offend anyone or create unnecessary controversy.. But after doing so many of my training courses, why not express it openly ?
My opinion, forged by observation and a long professional experience in pleasure boating (¹), is that this assertion of the systematic optimism of the GRIB forecasts regarding wind force, which unfortunately continues, no longer has a reason to be, and has not been verified in fact for some time. Read more …
Alternative weather models [Update]
[Updated 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 the meteorological services, all countries included. Applications like XyGrib, LuckGrib, SailGrib, Weather4D and other, offer a selection of atmospheric and oceanic models, up to 25 weather models and 15 waves and currents models 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 thunderstorms with Weather4D
In Weather4D (all versions) most weather models provide a data calledCAPE.
Convective Available Potential Energy, in French : Energie potentielle de convection disponible. Behind this abstruse acronym hides a powerful tool for forecasting thunderstorms. The CAPE is measured in joules per kilogram of air (J / Kg) and defines the vertical thrust 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
In an article updated in August 2020 (¹), I have described nautical books in digital format that can be usefully saved on iPad in the Apple Books app. Among them I mentioned the works of Météo-France available in PDF format for free download from their documentary portal.
In the “Courses and Manual” section of this site, we can download a new book, published 2020, entitled "Meteorological Observations and Measurements – Tome 1 / Clouds and other meteors ", a veritable mine of information on clouds, and all associated meteorological phenomena, called "meteors" (²). Read more …
You said « Medicane » ?
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 …
Introduction to Marine Weather [2021]
The new tutorial " Introduction to Marine Weather "Is available on the iBook Store (¹).
A complete reworking of the originally published book in 2015, new layout, clearer and more readable in portrait mode, ful revision of the text, updated videos and illustrations. Read more …
New major evolution of the GFS model
NOAA (¹) annouced on 22 March a major upgrade to its weather forecast model GFS.
For the first time, the Global Forecasting System (GFS), NOAA's flagship weather forecast model (¹) will be coupled to the global wave model Wave Watch III (WW3), produced by the FNMOC (Fleet Numerical Meteorology and Oceanography Center), which will extend the current forecast of waves from 7 up to 16 days and improve forecasting of atmospheric-forced ocean waves. Read more …
Sea state : interpret wave patterns
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 the FNMOC (Fleet Numerical Meteorology and Oceanography Center) of the US Navy, with a Global model due 7 days and resolution 1 ° (60NM), and a European model at 3 days and resolution 0.2 ° (12NM). Meteo France publish modelsMFWAM (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)
Friday 13 November will not be a lucky day for the Vendée Globe skippers 2020 (¹). They will have to negotiate the meeting with the tropical storm "Theta" which crosses their course with average winds which can reach the 40 knots and strong gusts. Especially the sea will be to fear because, strongly crossed when passing the low pressure center, the waves may exceed the 6 meters and surge chaotically. Read more …