Category : Meteorology

New GFS grid 0.25° model

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By a notification corrected the 23 December 2014 (¹), the NWS (National Weather Service) NOAA has announced a major update of its weather predictions GFS model to be effective in mid-January 2015. Actually, This model is partially available on an experimental basis since early December.

NOTE

The Global Forecast System (GFS) is a model of weather forecasts produced by the National Centers for Environmental Prediction (NCEP) dependent of the NWS. Dozens of variables (²) atmospheric and terrain are available through this data set, Since temperatures, winds and precipitation to moisture from the soil and the concentration of atmospheric ozone. The world is covered by the current GFS model with a horizontal resolution 27 km between grid points to 10 days. The horizontal resolution is 70 km for forecasts between one week and two weeks. The GFS model is a coupled model, composed of four distinct models (an atmospheric model, an ocean model, an Earth model, and a sea ice model), who compete together to give an accurate picture of weather conditions. Changes are regularly made to the GFS model to improve the performance and accuracy of forecasts. Gridded data are available for download via the NOMADS servers (National Operational Model Archive and Distribution System) and widely used by application developers in the world.

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Iridium GO! keeps its promises [Update]

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Since its announcement last February, the GO! is expected to come from dealers at the beginning of this month. Company E SAT gave me one to conduct some tests. Although too late to perform these tests at sea, the Quai des Antilles on the Ile de Nantes offers a wide sky clearance also than the deck of a boat, enough to connect satellites of all-round. Two types of test were conducted : requests and receipts of GRIB weather files from an iPad featured with Weather4D PRO app, functions related to the telephony from an iPhone.

Iridium GO! in the Buren Rings on the Quay of Antilles. An invitation to travel ?

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Weather4D still makes greater finesse

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With the basic 1.3.3 and PRO versions 1.3.9 delivered in November, Weather4D had replaced the GRIB files fine grid from Great Circle by its own files based on the U.S. model WRF (¹), computed under his own steam. These files covering Europe, Greece, Canaria, Azores, Greater and Lesser Antilles, offer a resolution of 0.1 ° (6 NM) up to 96 hours by 1 hour steps. The data provided are the same as the GFS model (¹). At the same time, Annual subscription price has been reduced from 60 up to 30 €.

With the introduction of new ways, the next updates that have just been submitted to Apple Store will provide more details. Olivier Bouyssou explains :

« FYI, App4Nav uses 6 different servers, 2 for the calculation of WRF model and 4 for distributing GRIBs : 2 for the U.S. and Asia region 2 for Europe. At this time 8000 GRIBs are distributed per day and triple during the season… "

This now enables to provide, for the French coasts, including Corsica, ultra-fine grid to 0.04 °, that to say 2,4 NM. It also adds to the GFS and WRF files new data evaluating wind gusts. Read more …

Weather4D PRO 1.3.2 adds the currents in the routing

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weather4d proWith version 1.3.2, Weather4D PRO allows to get and display currents as GRIB data. At first, currents available are provided with subscription by Tidetech, I mentioned there in the past (¹). Once entered in Weather4D PRO settings a username and password, provided during the subscription, you can access Tidetech global catalog.

Only a PRO subscription to Tidetech provides GRIB format files. The company is considering a specific offer for applications on iPad / iPhone. Read more …

iNavX 3.6.1 with high-resolution GRIB files

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Since version 3.6.1 iNavX provides overlay of GRIB weather files in high resolution from theyr.com. This English website owned by Kona Ltd company is the developer of the application GribView I mentioned in a previous post (¹). An active account on x-traverse.com must be open, and done subscription to one of the Theyr subscriptions.

Actually x-traverse.com website allows two subscriptions :

  • Theyr Standard – Mobile price annual from $9,99 (about 7,85 €) or monthly from $3,99 (about 3,10 €)
  • Theyr Premium – Mobile price annual from $19,99 (about 15,70 €) or monthly from $6,99 (about 5,40 €)

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Atlas of the Oceans, Pilot Charts revisited

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Atlas des OcéansThe Atlas of Oceans by Jimmy and Ivan Cornell is a gold mine in color A3 size of over one kilogram. This one will not fit in an iPad !

60 pilot charts updates to the most recent data, 69 transoceanic route charts, remarks and suggestions for tactical choice of the best times of crossing provided by routers and meteorologists each zone.

It had the passion and experience of the author of famous " World Cruising Routes " (*) and those of his son to perform such work. Read more …

Navigation with iPad trainings : a complete solution

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With Weather4D PRO and Iridium Mail, associated with a satellite phone Iridium, we now have a complete solution, reliable and low cost to receive, display and manage GRIB files in open seas with iPad.
iNavX and Navionics cartography also provide a complete navigation solution, supporting files transfers with Weather4D PRO : GRIB, routes, tracks, that allows simultaneous display in both applications.

These solutions, fully complementary and mutually consistent, were tested on more 2800 NM in the automn during a crossing from Canaria to the Caribbean, on board Catana 47 " Gust ", token place in ARC rally 2011. In addition, Olivier Bouyssou was able to improve his Weather4D Pro application "over time", correcting, adding and optimizing daily development onboard. Read more …

Weather4D PRO 1.0 includes routes from iNavX

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Weather4D ProThe new application Weather4D PRO for iOS (iPhone / iPad), developed by Olivier Bouyssou, was submited yesterday to Apple. It provides advanced features associated with GRIB files for demanding users. It comes in addition to Weather4D app which was promoted as one of the best apps in Apple AppStore for few weeks.

This Pro version, quickly available, will provide following features :

GRIB files management :

  • Import, sharing (export ), copy-paste, folders filing, history, request from SailDocs by email

Routes management :

  • Route import in KML format from iNavX or other apps, overlay route display with forecasts, boat progress with forecasts scrolling, route settings (heading, speed, date, etc. ...).

Iridium satellites tracking :

  • Prediction of transition from Iridium satellites to optimize the connections to run queries GRIB files. Automatic updating of ephemeris and parameter setting coverage (rising, timing). Read more …

When Katia meets La Louise

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Thierry Dubois and his crew, whose Jacques Vermeulen experimenting its Iridium connection with its new MacBook Air, should not laugh at a time when I post this short note.

La Louise, conveying from Newfoundland to La Trinité, is in the making up of Hurricane Katia, ex-tropical cyclone, which must reach the shores of the British Isles the next night. According to the latest position and the estimated speed, La Louise should be in the west of the weather area "Romeo", either in the southeast of the center of the Low, its intended position on the Navimail map below the location of the red boat at 18h UTC : Read more …