Technical & Equipment from Ocean Sailor Magazine

Grab the GRIBs

Grab the GRIBs

If ever a digital invention required an acronym it’s ‘General Regularly-distributed Information in Binary form’, GRIB to you and me. 

To decode and view the grib data, you will need a grib viewer or viewing app. There are many options available that present the forecast in different ways, or have varying levels of complexity. Below are a few examples.

Due to the high cost per megabyte involved with satellite communications, using traditional weather services or apps are impractical when sailing offshore, weather GRIB files were invented to provide a low-cost alternative for weather forecasting. 

Instead of sending a large picture or weather map file, the weather data is sent in the form of computer instructions that require a special viewer to decode the data and present the forecast. Apps such as Windy or PredictWind not only use very large amounts of data, they also do not give the reader such a clear understanding as the more basic data provided from GRIB files that illustrate the weather systems with isobars.

Depending on the platform you prefer to download, i.e. Windows, Mac, tablet or phone, there are various options available to you. Whatever platform you will use you will need to download the grib file. The most cost-effective way to download these files offshore is to use an email service. There is a process you need to learn depending on the service used, details are on their respective websites.

Most of the apps and files will download a full profile of the weather conditions and allow the user to select which elements of the forecast data they wish to use. Whilst it’s tempting to request all data files, this will greatly increase the download time and increase the airtime cost, also the forecast chart will become cluttered and less clear to use.

We suggest a sailor limits their data to; wind strength, pressure and Cape. This acronym stands for ‘convective available potential energy’. In short, this means the propensity a given area has for a depression and later a storm to be created. You could justifiably leave that to the weather professionals since if you keep up to date with the 5-day forecasts, they will show a depression forming. 

We advise requesting twenty-four hour forecasts for up to 5 days ahead since we have noticed that the longer-term forecasts become less reliable, and again it limits the data stream used.


Teleport weather by Mailsail

Teleport Weather is provided by Mailasail the same company that supplies the Red Box wireless router system that integrates with the satellite, WIFI and 3G/4G communication services, so offers a unified onboard communications platform featuring low-cost routing, wireless NMEA instrument data, firewall, enhanced GPS tracking, crew email and web optimisation.

Platform:

Teleport Weather is provided by Mailasail the same company that supplies the Red Box wireless router system that integrates with the satellite, WIFI and 3G/4G communication services, so offers a unified onboard communications platform featuring low-cost routing, wireless NMEA instrument data, firewall, enhanced GPS tracking, crew email and web optimisation.

Covers: Wind, pressure sea level and above, waves, CAPE, air and sea temperatures

Website: weather.mailasail.com

Cost: £10 a month


Sail DOCS by Sail docs

Platform:

Sail Docs was the first GRIB service designed by sailors for sailors. It is the most economical and flexible service available but is a little clunky to use. 

Covers: Wind, pressure, rain, CAPE, waves, air and sea temperatures

Website: saildocs.com/gribinfo

Cost: Free


LuckGrib by Craig McPheeters

Platform:

The presentation style is very clear and there are additional features like route planning built-in. Grib files can be downloaded through the app with a high-speed internet connection or imported from other services such as MailaSail or SailMail when offshore. Bear in mind that LuckGrib is designed for Apple systems and is only available on Mac or as an iPad app.

Covers: Wind, pressure, sea level and above, CAPE, rain, snow, dew point, cloud cover, waves, currents, relative humidity, air and sea temperature.

Website: luckgrib.com

Cost: £23.99


PocketGrib by Nicko Brennan

Platform:

Extensive range of tools and the charts are clearly presented but the area selection is via a graphic chart which does consume more data and airtime.

Covers: Wind, rain, pressure, air temperature, cloud, relative humidity, CAPE, waves (including the Mediterranean and the Black Sea,) Current (Atlantic only). Up to 8 Day Forecasts.

Website: pocketgrib.com

Cost: £5.99


SailGrib by Sailgrib

Platform:

As a free version will only show 2-day forecasts. The app offers a variety of presentation formats and also has a weather routing app available.

Covers: Wind, pressure, rain, cloud, air temperature, waves, CAPE, tidal and oceanic currents.

Website: pocketgrib.com

Cost: Limited free version. £7.99 plus £45.99 for routing app


XyGrib by Opengribs

Platform:

A versatile option for laptop-based systems. It offers many data options as well as various presentation choices. Weather can be downloaded from within the app or opened from other sources.

Covers: Wind, Pressure, CAPE, Rain, Snow, Dew point, Cloud Cover, Waves (Height/Direction/Period), Currents, Air and Sea Temperature, Relative Humidity

Website: opengribs.org

Cost: Free


Our Favourite

Our current favourite is LuckGrib since its charts are very clear and show the weather systems and the isobars that delineate them well. The above is a selection of GRIB file readers, but there are many other options available in the form of apps or desktop programs.

For further information on viewers please visit – https://weather.mailasail.com/Franks-Weather/Grib-File-Viewers

For further information on apps, please visit – https://weather.mailasail.com/Franks-Weather/Grib-Files-Apps#Mobilegrib

Many thanks to Mailasail for providing information.

Share this post

Share on facebook
Share on twitter
Share on linkedin
Share on pinterest
Share on print
Share on email

Keep reading

There’s plenty more to read at Ocean Sailor. Check out some more Technical & Equipment articles …

Thank you!

Your Friend has been subscribed