WEATHER ARTICLE ice without the cumbersome scripting. Requesting WEFAX documents through saildocs.com is both faster and easier than using the NWS FAX-Back service. A request to Table 2 Saildocs for the same Saildocs Request documents requested in the NWS To: query@saildocs.com example is shown in From: yourcall@winlink.org Table 2. The request Subject: Anything or leave blank format is simple and send ppae11.tif send pyeb86.tif easy to understand send pyfa96.tif the command send followed by a space and then the document file name. The retrieved documents are the identical NWS documents returned by the NWS FAX-Back system. The best way to get started with Saildocs is to e-mail a request and put send help and/or send info in the text portion of the message
GRIB Files Both the Sailmail and WL2K networks handle Girded Binary (GRIB) wind prediction files. GRIB forecasts are based upon the NOAA GFS/AVN global computer model, not actual reported conditions. The GRIB wind prediction data predicts general wind flow, and is a useful tool when used in conjunction with other weather forecasting and analysis tools, but it should not be used as a stand-alone predictor. It’s important to bear in mind that these GRIB data are not reviewed by meteorologists, and they do not allow for frontal, tropical, near-shore, geographical, or other local effects. GRIB files are requested through the Catalog Tree screen in Airmail. Skippers using Airmail for Sailmail will find the Catalog Tree on the Message Index Screen by clicking on WINDOW, CATALOGS.
downloaded in about three minutes, four times faster than with Pactor-II. WL2K users can use either Pactor-II or Pactor-III, since they may remain connected up to thirty minutes per session per server station. If you need more information about the Pactor-III speed upgrade, send an email to pactor3@docksideradio.com.
Footnotes 1
WEFAX broadcast station listings and schedules are available from the National Oceanic and Atmospheric Administration (NOAA). The publication Worldwide Marine Radiofacsimile Broadcast Schedules can be downloaded at http://www.nws.noaa.gov/om/marine/rfax.pdf. 2 Airmail is a client program that runs on the shipboard computer and communicates with Sailmail and/or WL2K network server stations. 3 Sailmail is a network of private coast radio stations that transfer e-mail messages between cruising boats and the Internet. 4 Winlink2000 is a network of amateur radio stations that transfer e-mail messages between amateur radio stations and the Internet. About the Author: Gary Jensen owns and operates DockSide Radio (www.docksideradio.com) and specializes in Sailmail & Winlink e-mail systems. Gary and his wife Peggy lived aboard their Hans Christian 38T for three years, cruising the West Coast of the U.S, Mexico, and the Sea of Cortez. They now live in Punta Gorda, FL, and Gary can be reached at (941) 661-4498 or by email at pactor3@docksideradio.com.
A word about file size Limitations. Sailmail network users must be running Pactor-III if they are to keep within the ten-minute on-air connection time limitation when receiving GRIB and other weather files. Weather files are relatively large, averaging about 35KB in size, and Pactor-II isn’t fast enough to transfer some of the larger files and stay within the ten-minute connect time limitation. Running in Pactor-III mode, a file that would take around 12 minutes to download running Pactor-II can be
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December 2004
SOUTHWINDS
www.southwindssailing.com