Frequently Asked Questions

How do I read a wind barb?

The wind barbs indicate both the wind speed in knots (nautical mile per hour) and the wind direction (from which the wind is coming from). Each flag on a wind barb indicates 50 knots, each long segment is 10 knots, and each short segment is 5 knots. To get the wind speed, just add up the flags and segments.

Where are the ship callsigns?

Please note that we have removed all ship callsign references on the various images and no longer produce text tables of marine observations. Additionally, all ship traffic from specific regions has also been removed. This change is in response to requests made by the Voluntary Observing Ship program. These changes were implemented to preserve the transmission of ship data between national weather centers as they are an invaluable source of marine data which we apply in our global and regional forecast and hindcast modeling.

Can I get archived data?

We do not routinely archive the images that are produced on this site. The source data (observational and model data) is archived, but will there will be cost involved in accessing any part of Oceanweather's database. Normally this is reserved for commercial applications.
How is the wave analysis produced?
Since we produce our own wave forecasts we are very proud of the techniques we use and our forecast skill. Please check our History and Approach to Oceanweather Forecasting page.
I live X miles from Y beach, should I go surfing tomorrow?
Oceanweather has partnered with Swell Navigator, which is a surf spot forecasting app. Click here for more information and to download Swell Navigator.
Where do the ship observations come from?

Ships that are part of the VOS (Voluntary Observing Ship) program report weather in realtime and this information is forwarded to weather centers around the globe. The NOAA VOS page gives more information.

Why can't I see all the navigation links on the left?
You'll need to be at a minimum resolution of 768x1024 and have your web browser full screen in order to see the full list (you'll also be able to see more of the images). You can also click on the map image on this page to view any region. Below is the list of available regions in case you can't run at this resolution:

What are the different color wind barbs on the marine observations page?

Observations are color coded by type. Buoys are shown in red, ships are shown in blue and C-MAN (Coastal-Marine Automated Network around the U.S.) are shown in magenta.

What are the gray contours on the marine observation images?

They are sea level pressure in millibars (mb). The labels are "short hand" that show just the last two digits: 998 mb becomes "98", 999 mb is "99", 1000 mb is "00", and 1001 mb is "01" and so on.

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