![]() ![]() ![]() There are primarily two ways to grab a weather chart off the Internet. This bypasses the email system and the exactitude of the FTPmail service, but it introduces its own challenges. Instructions and fine print are available at or by sending an email to with the word help in the body of the message.Direct download of weather chartsĪnother way to get the same weather charts in a more direct manner would be to download them directly from the Internet. While the service has been very reliable, there may be times when it’s unavailable. Keep in mind that the FTPmail service is not an official operational delivery method, which means that there are no guarantees. Lists of charts and filenames are available at these websites: And capitalization is important: A request for pyaa12.tif won’t return anything, but a request for PYAA12.TIF will get you the chart you need. For instance, you can’t simply request the latest surface analysis for the western Atlantic, you need to specifically request file PYAA12.TIF from the /fax/ directory. It’s also not the most user-friendly service, as you must know the specific filename for each chart and where on the server the chart is stored. The service won’t reply with an error message telling you about a malformed request it just won’t respond at all - leaving you in the unfortunate situation of wondering whether your request is just taking a while or whether it just won’t ever be processed due to a typo. One disadvantage of the FTPmail service is that it’s a very, very exact science, and even the slightest typo in your email will result in a failure to receive any charts. However, receiving these charts over Iridium, Globalstar or Inmarsat MiniM is very reasonable, as shown in table one. The size of the charts might also strain the capacities of most single sideband email providers. The FTPmail service works over just about any email-at-sea service, though receiving these charts over Inmarsat C would be prohibitively expensive at almost $300 per chart. The length of time needed to receive a response can vary greatly, though most charts should be returned within an hour of your request. The charts are then attached to a reply email that gets sent back to you. Once the message is received, the instructions within are analyzed and a list of charts prepared according to the sender’s request. The email is sent to a special destination that automatically handles all incoming requests without human intervention. The gist of the service is that you compose an email (at home, on the boat, wherever) that includes instructions detailing which charts you’re interested in receiving. The concept is known as FTPmail, which is an extension of the file transfer protocol (FTP) in common use on the Internet. Thanks to the efforts of Tim Rulon, Cliff Fridlind and others at the NWS, weather charts are now available on demand via email. Downloading and printing these charts at home before a passage is relatively easy, though accessing them while you’re at sea may be a bit more of a challenge.Weather charts by email You can find many of these charts at (for the waters north of 30° N), (for the waters south of 30° N), or. The National Weather Service (NWS) has been aggressive about publishing their chart products on the Internet and making them available for free to anyone who wants to spend the time to find and download them. And many folks are going even beyond that and finding alternatives to the radio-based charts. Instead of black-box fax printers using rolls of thermal paper, most vessels are receiving these charts on a computer hooked up to their single sideband radio. They continue to be a valuable piece of the weather forecasting puzzle, but recent changes in technology offer more options to the mariner that were not available previously. As a “cordless fax,” it was an idea ahead of its time.įor almost 40 years, weather charts received by radiofacsimile (or more simply, weatherfax or radiofax charts) were a mainstay at the nav station of any vessel venturing offshore for more than a few hours. Mariners would have a large black box that received the radiofacsimile from the airwaves via a radio and then printed out the chart embedded in the incoming signal. Initially, charts were drawn by forecasters and then placed on a cylindrical drum, from which they were scanned and sent out over the airwaves as a radiofacsimile. The technology was first used in 1926 and has changed very little since 1965, when the modern weatherfax program began. Gone are the days of the old, simple weatherfax. ![]()
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