From the Winlink/Airmail system:
YOTREPS is a voluntary reporting scheme for boats on passage
, created by long-term cruiser Mike Harris. Airmail provides a page in the Position Reports window to create Yotreps reports, see Position Reports- Yotreps for more information. Mike provided the following introduction
to the Yotreps system:
All boats on passage
, anywhere in the world are welcome to take part in Yotreps, and it's free. Benefits of reporting are:
A personalized web page showing a plot of your last 30 reports within the last year.
Reports are routinely forwarded to weather
forecasters who use the 'on the spot' observations as a check on the accuracy of their atmospheric modeling, and so contribute to the overall accuracy of forecasts.
In return, in some areas, notably the south Pacific
, forecasters provide a long- term prognosis of weather
prospects for boats contemplating passage.
Reports are also forwarded to search and rescue
co-coordinators. In an emergency
, this enables them to see an up-to-date plot of boats in a particular area and so provides a vital information base from which to make decisions on which vessels are best placed to render assistance.
Reports contribute to a database of passage weather observation for analysis of trends in ocean cruising weather conditions. Where there is sufficient data, a web page provides a historical review of conditions experienced on popular cruising routes.
The YOTREPS report distribution and position plotting system is entirely automated. The system will reject reports that don't fit the standard format, and return an error message. So before submitting a report and to avoid frustration, please make sure that you understand what is required. The most up-to-date source of information is the YOTREPS web site which contains, not only the boat position plotter, passage analysis pages and free software
downloads, but also full details of reporting protocols and a page of Frequently Asked Questions. If you have any questions not covered by the FAQs please contact email@example.com
Also on the web site is 'Vessel Details' form. So far, the largest vessel using YOTREPS has been the 'Queen Elizabeth II' and the smallest an 8 metre cutter
'Discovery II'. You can remain anonymous if you wish, but filling this out helps to let us know who you are and something of your perspective on ocean weather.
Note for YOTREPS reporters
1) If you've not already done so please check out the YOTREPS web site (www.pangolin.co.nz/yotreps
) for the latest updates on reporting protocols.
2) Please only send YOTREPS reports while on passage and not from shoreside locations, ports
3) Please send no more than one report in 24 hours. If you make an error, sending a repeat will not correct the problem.
4) Please use only UTC times and dates. Reports received at the server more than 24 hours after their validity time, or reports with future dates are rejected.
5) YOTREPS reports are routinely forwarded to search and rescue
coordinators, met. forecasters and are used in an ocean passage weather analysis web page. For this reason, weather observations form an important part. One or two blank observation fields are acceptable but reports with no weather observations are rejected.
6) Reports remain in the web site data base for about a year. When you have a few in the system the following URL can be used to show a plot of your last 30:
where ID is the identifier used on your reports.
It's surprising how a report of even the simplest observations can be open to a variety of interpretations. When talking of the date and time, for example, do we mean the local time with any adjustment for daylight saving, or perhaps Zone, or Universal time? If we specify a compass
course, do we give what the compass
actually reads or is it corrected it for the local magnetic variation? When reporting boat speed, would that be our speed through the water
, or the speed over the sea bed
? When exchanging information between people from different backgrounds, cultures and experience, it is absolutely essential to be sure that we are speaking the same language. Fortunately, with marine
weather reporting, there is already a widely used, internationally agreed standard that has been in regular use for many decades.
The World Meteorological Organization (WMO) Voluntary Observing Ship scheme (VOS) uses a system of encoding (BBXX) that firmly defines the parameters to be given in weather reports. It is these, with some small noted differences, that are used in YOTREPS reports and are as follows:
Parameter Units Explanation Note
Date and time UTC UTC (Coordinated Universal Time which for the purpose here is synonymous with GMT (Greenwich Mean Time)
Position Degrees and min Report to the nearest whole number of minutes and do not use decimals.
Boat course Degrees true Boat's course through the water
. (Not necessarily the same as the boat's heading) 1
Boat speed Knots Average speed over the last 3 hours to the nearest whole number. Speed reported should be the speed over the ground. 2
direction Deg true or Compass points Direction of the true wind
. To obtain this use either the Beaufort
Scale or correct the masthead wind indicator reading for the boat's speed and course.
Wind speed Knots Average speed of the true wind. To obtain this, use either the Beaufort
Scale or correct the masthead anemometer reading for the boat's speed and course.
Swell direction Compass points Direction of the main ocean swell.
Swell height Metres Vertical distance from trough to crest and the average of the larger well formed swells.
Cloud cover % Proportion of the sky covered by cloud 3
Pressure HPa Barometric pressure
Pressure tendency + or - hPa Pressure change over the past 3 hours. Prefix with a plus or minus sign to indicate rising or falling. Report 0 if steady
The course reported should be obtained by correcting the compass heading for deviation, magnetic variation and leeway.
Except when in a strong current
, which is unusual on an ocean passage, speed over the ground will be very similar to speed through the water and could be measured by electric
or mechanical log, GPS
set or visual estimate. Remember to report the average and not peaks that might perhaps occur when surfing down wave fronts.
To estimate cloud cover, imagine the sky divided into quarters like a cake. Imagine each quarter further divided into two parts
; each segment forming one eighth of the total sky. These are known as oktas and are the unit of cloud cover used by professional observers. Perhaps because the okta is not widely familiar, cloud cover is often reported as a percentage. Multiply the number of oktas by 12.5 to convert to a percentage.
There are other reporting systems as well...