Thursday, August 13, 2015

High Seas Forecasts and Tropical Cyclone Alerts by Email Request

In several articles we point out that standard analysis and forecast maps of tropical systems do not have nearly enough information on them to make weather routing decisions.  We need more information. One approach is to download a GRIB formatted numerical prediction. The GFS is the most popular; the NDFD would be superior if that were available to your waters.

With or without these GRIB files, it remains valuable to also obtain the text forecasts from the NWS, in part because the GFS—or any one single model—can sometimes be quite a bit off on the tropical system intensity.

We have three basic text reports that might be of interest: high seas forecasts, high seas discussions, and tropical cyclone alerts. The basic ones we need to supplement the maps are the forecasts, and these are easy to get.

In principle we can get all of the text reports we need from the NWS FTPmail service, but this requires a very specific format and list of file names. An alternative is the excellent services of Saildocs, which have proven very dependable and versatile; it is relied upon by thousands of mariners worldwide, so we will limit the source to this one.

The eastern half of the Pacific Ocean is in the IMO GMDSS forecast zone called Metarea XII; the western half of the Atlantic Ocean is in Metarea IV. 



To get text report and forecast for Metarea XII (North Pacific)

send an email to query@saildocs.com with the body of the text blank except for 
send met.12  You can put anything in the subject line, which can serve for finding the mail for a repeated request. Be sure there is no signature or other text or graphics in the body.

This is all there is to it.  Try it here.


You can also subscribe to this request to have it sent to you automatically every day.  Send a blank email to info@saildocs.com for details.

For other metareas, use these Saildocs abbreviations


Code Metarea description
Met.1a      North Part of North Atlantic Ocean (High Seas)
Met.1b      Northeast Part of North Atlantic Ocean (Offshore)
Met.2       East Part of North Atlantic Ocean
Met.3e      East Mediterranean Sea
Met.3w      West Mediterranean Sea
Met.4       West Part of North Atlantic Ocean
Met.5       North Part of South Atlantic Ocean
Met.6n      South Atlantic Ocean North of 60S
Met.6s      South Atlantic Ocean South of 60S
Met.7       Southeast Atlantic Ocean + extreme SW Indian Ocean
Met.8n      North Indian Ocean
Met.8s      Southwest of Indian ocean
Met.9       Red Sea, Gulf of Aden, Arabian Sea, Persian Gulf
Met.10ne    Northeast of Australia (Pacific ocean)
Met.10n     North of Australia
Met.10w     Southeast of Indian ocean
Met.10se    Southeast of Australia (Pacific ocean)
Met.11ior   West part of the North Pacific Ocean (from China)
Met.11por   West part of the North Pacific Ocean (from Japan)
Met.11sW   West part of Pacific Ocean, 0-12S 90E-142E approx
Met.12      East part of the North Pacific Ocean
Met.13      Northwest of Pacific Nord and part of Arctic waters
Met.arctic  From SW corner 67N, 44E to NE corner 80N, 165W
Met.14s     South Pacific south of 25S
Met 14trop  South Pacific north of 25S
Met.15      Southeast Pacific
Met.16      Southeast Pacific between 18S and 3S)



We can also see these reports online two ways. Directly from the IMO see
http://www.jcomm.info/index.php?option=com_content&view=article&id=105&Itemid=37

and we have similar reports from the NWS from this folder:

http://weather.noaa.gov/pub/data/forecasts/marine/high_seas

The files matching metarea XII and IV are  north_pacific.txt  and  north_atlantic.txt



If you are sailing across one of these oceans, you would want to set up a schedule with Saildocs to send you the text report at least once a day, automatically.  This will supplement your maps and GRIB file weather analysis.

You can of course get this information from the HF radio. The USCG broadcasts voice versions of the above forecasts 4 times a day. See http://www.nws.noaa.gov/om/marine/hfvoice.htm


* * *
Any of these services that might potentially be used underway 
should  be thoroughly tested before departure. 

* * *


2 comments:

David Burch said...
This comment has been removed by the author.
David Burch said...

I just found in our own product called Weather Trainer Live another option that includes more information, but there is no short cut. To get it, send this email to query@saildocs.com

for the Pacific:
send http://www.opc.ncep.noaa.gov/shtml/P_brief_text_P.shtml
or
for the Atlantic:
send http://www.opc.ncep.noaa.gov/shtml/A_brief_text_P.shtml

These will include the metarea reports (discussed above), and also include the Forecast Discussions and the Offshore waters Forecast, which would make this better for coastal cruising.