Recently we told you about navigation apps that help you keep your bearings at sea, so now let’s take a look at weather apps, which can put the power of the world’s best weather forecasting right in the palm of your hand. Whether you’re waiting at the dock for a rainstorm to blow past, out on the bay dodging thunderheads, or deciding if a long run is do-able, these apps will help you make the right decisions.

Predict wind 3

The Predict Wind map overlay showing wind speed and direction is simple and quickly understood.


This iOS app gives access weather forecasts generated by both the American GFS model and PredictWind’s own high-resolution model that includes land data to allow for local geographic effects such as sea breezes. On registering you get free access to forecast data for up to 48 hours ahead, as well as automatic login to the app. An extension to download five-day forecasts – plus observation data covering the previous 48-hour period – costs $18.99 for 12 months.

Forecast data are presented in a number of views, including a table that’s quick to scan for a specific location. Alternatively the data can be overlaid on a map that shows predictions for a wider geographic area in three-hour time steps. There’s also a graph that enables the predictions of the two models to be directly compared to each other. This is very useful in determining whether models agree and, if not, in identifying the likely range of possible weather.

An optional trip-planning function identifies the best day on which to depart for a longer voyage. Similarly weather routing, including the fastest route across the wind, swell and currents, is available as an in-app upgrade costing $4.99 for a five-pack.

For coastal sailors and motorboaters, PredictWind is a commendably intuitive package that brings together a large amount of complex data and presents it in a way in which it’s easily understood and remembered. For those who sail farther afield, the Trip Planner and Routing functions successfully emulate the essential elements of software that normally cost many multiples of this price.


This app for iOS devices uses the gridded binary data format that is used to distribute historical and forecast weather data with the smallest file sizes possible. Downloading grib files directly to the device is an easy matter and can be done using auto-locate so that only two soft-button presses are needed.

Pocket Grib 5

PocketGrib makes a number of data sets available, like wind speed and direction, precipitation, and atmospheric pressure.

The data available includes wind speed and direction, precipitation, atmospheric pressure, cloud cover, wave height, and humidity. It can be presented as meteogram graphs, overlaid on a map, or tabulated. All are commendably clear and easy to follow: A small barb represents 5 knots of wind speed, each long barb 10 knots, and a solid triangle barb 50 knots. Optional colored barbs make different wind strengths even easier to identify.

Time interval steps are adjustable, with a choice of three hours, six hours, or 12 hours, while for geographical resolution you have a choice of half-degree (30 mile), 1-degree or two-degree squares. Obviously the finer the resolution and the more data functions you enable, the large the file size, which has important cost considerations if roaming overseas or if downloading grib files from a satellite phone when well offshore and out of mobile phone range. However, this is still the most efficient way of obtaining this data.

Overall, PocketGrib is easy to navigate. It’s easy to customize settings to suit different requirements, and is clearly a useful tool in the navigator’s armory.

Yachting Weather

The free version of this app provides forecast data for six-hour time steps up to 48 hours ahead. Upgrading to the Pro version costing $7.99 gives five-day forecasts in three-hour steps, including gust predictions and gains the benefit of ad-free pages.

There are two ways to select a location for the forecast, either by typing the name of the place, or by dropping a pin on the screen. The former we found easy, although the latter was not always so straightforward as the pin could not be moved once activated.

Yachting Weather

Yachting Weather's forecast data include cloud cover, temperature, wind speed and direction, precipitation risk, wave height, and other information.

The comprehensive forecast data is presented on a page for each time period that shows the amount of sun or cloud, temperature, wind speeds and direction, storm risk, precipitation risk, wave height, length, and period, plus pressure, humidity, and rates of precipitation. Scrolling between time periods is easy -- a single swipe in either direction is all that's needed.

However, flicking between different locations is not such a straightforward process -- you have to return to the map each time, placing a new pin if necessary, and then wait for the data to load -- even if you looked at that location only a few minutes earlier. Overall, this is still a neat app, with extensive global coverage, but it is perhaps best suited to those who only need to look at a handful of different locations on any particular day.

  • Supported devices: iPhone 3G/3Gs/4/iPad

  • Version tested: 2.12 for iPhone/iPad

  • Price: free/$7.99


Bluefin Marine Weather

Bluefin's Marine Weather covers all US waters, as well as the Caribbean down to the coast of South America.

Marine Weather

Bluefin’s Marine Weather app uses data from the UK Met office, the Proudman Oceanographic Laboratory, and Ireland's Marine Institute. This can be overlaid on a map or satellite image to show weather forecasts, live observation data, or times of sunrise and sunset. Simply click on each sea area to bring up the latest shipping forecast for that area, as well as the relevant inshore waters forecasts. There is also an outlook for the following 24 hours and an extended outlook beyond that.

Even better, it can overlay real-time Doppler radar on the map, with a history going back several hours. That allows for animation, so you can see which way the storms are tracking and how they’re developing.

Overall, the free version is useful in that it shows both shipping forecast and inshore waters forecasts in one place. However, the number of locations from which observation data is available is limited and there are better tidal prediction programs.

  • Supported devices: all Android, Blackberry, and Apple devices

  • Version tested: 1.5.1 for iPad

  • Price: Free


WeatherBug's map interface shows precipitation in radar loops, and is marked with the user's saved places.


This popular (and free) app is on both iOS and Android platforms, covers the entire continental US, offers GPS-based and point-and-touch location abilities, still-image Doppler radar on maps, and includes additional weather data from proprietary weather stations (the “Weatherbug Network”).

Upgrading to Weatherbug Elite, which costs $1.99, eliminates advertisements and enables radar animation, lightning tracking, humidity information, barometric pressure data, and wind speeds. It can also be set to give automatic alerts, in case of stormy weather.

This app is very simple to use, and clicking between regions, switching between data views, and navigating through the menus is a breeze. It’ll be quite helpful to mariners of all types, though upgrading to the Elite version will greatly enhance its utility.

  • Supported devices: all Android, Blackberry, and Apple devices

  • Version tested: Mobile for Android

  •  Free/$1.99


- Rupert Holmes