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[Wait For Weather] [Long Term Outlook] [Intermediate Forecasts] [Short Term Predictions]
Weather -  trying to avoid the bad stuff - is an all-consuming topic for cruisers.  Resources for predicting it range from long term climate information to direct warnings from satellites overhead.  Pick and area of interest and read on!

Wait For Weather

The basic rule we use for  avoiding trouble is to wait until the weather is the way we want it for the upcoming passage.  Sometimes we want light winds to ease into a trip, other times we want to leave on the tail of a weather system that will help us along for a day or so.  The corollary to this rule is that most forecasts are 50-75% accurate for 2-3 days, beyond that they are unpredictable.

Long Term Outlook

The long term outlook is what we, and most long-distance cruisers, use to plan where we will be during each season: 

  • Tropics during the Winter
  • Equator or temperate region during the cyclone season
  • Move with the trades and seasonal winds. 
  • Move between tropics and temperate zones during Autumn and Spring.

This outlook is based on climate observations over many years, and on average, are reasonably accurate.  Of course weather does not always behave like the averages - out of season storms occur or other anomalies may affect this year's cruising, but using this information for planning where to be each season is the still the best approach. 

The cruiser's bible is World Cruising Routes by Jimmy Cornell - information about it and other sources of long-term weather prediction can be found on our Books page.  For those cruising the Pacific, the state of El Niņo is important, and information can be found at the El Nino site

Intermediate Forecasts

All forecasts observe current conditions and use models to predict what will happen over the next few days.  We have learned a few things about the forecasts and the methods of delivery to the cruiser.

Forecasts

Weather forecasts of interest to most cruisers are produced by meteorological offices of various countries around the world (there are also a few private forecasters).  Accuracy depends on time and the model used. Our experience shows something like: 

  • 24 hour     75% accurate, 
  • 48 hour     60% accuracy
  • 72 hour     <50% accuracy
  • >72 hours  indicative information only

The US, Britain, and France have the most widely used models. We have been most impressed by the French models, particularly when we were in New Caledonia - we compared their predictions with actual conditions for approximately 15 days in 1998 and found them very accurate.  As cruisers we have no control over the models used - we get whatever information is available in the cruising area.

Methods of delivery

The forecasts produced by the Met services get to the cruisers by many means.  Some of them are:

Method
Provider Features
Voice Forecasts
  • Government and private
  • HF and VHF radio
Norfolk, Va, US - NMN 'Mechanical Mike' voice synthesizer
Land-based radio nets for cruisers (see more details below) -HF radio, (Marine or ham bands)
-Run on schedule
-Relay gov't forecasts
Other cruisers -HF or VHF radio; ad-hoc
-Relay recent observations
Australia 2201, 4134, 6206, 8176, and 12365 kHz time-shared by stations around the country:
  • Darwin at 0833 and 2233 UTC
  • Townsville (tbs)
  • Brisbane (tbs)
  • Perth (tbs)
  • Sydney (tbs)
HF Weatherfax-
  • Government run
  • HF radio
  • Broadcast on schedule
  • Usually cover large areas
  • 12 to 48 hour forecasts
Halifax, Canada - CFH 4271, 6496.4, 10536, 13510 kHz
Boston, Mass, US - NMF 6340.5, 9110, 12750 kHz
New Orleans, La, US - NMG 4317.9, 8503.9, 12789.9 kHz
Kodiak, Alaska, US - NOJ 2052, 4298, 8459 kHz
San Francisco, Ca, US - NMC 4346, 8682, 12730, 17151.2, 22527 kHz
Honolulu, Ha, US - KVM70 9982.5, 11090, 16135, 23331.5 kHz
Australia AXI: 2628, 5100, 11030, 13920, and 20469 kHz
AXM: 5755, 7535, 10555, 15615, 18060 kHz
New Zealand 5867, 9459, 13550, 16340 kHz
Other Countries To Be Supplied. 
Text Forecasts
  • Mostly private operators
Inmarsat -Need $2000 Inmarsat satellite receiver
-6 to 72 hour forecasts
-Focused on area near receiver
Internet
See our Weather Links
Direct - The following Met Offices have provided useful weather information directly to us on request:
New Zealand Auckland (at Boat Books) and their HQ in Wellington 
Australia Most major towns  - Darwin was very helpful
New Caledonia Met service in Noumea provided great long term forecasts - practice your French.
Bermuda US Navy 
American Samoa Met office near airport
French Polynesia Each island has a met station

 

Land-Based Cruiser nets

There are a number of radio networks around the world where volunteers provide information or service to cruisers.  Usually they are ham operators or ex-cruisers who operate radio stations on land and perform functions like:

  • Track yacht locations
  • Relay messages between land stations and yachts
  • Relay weather forecasts from Weather Services and other cruisers

The ones with whom we have had experience include:

Area
Net Time freq Notes
Atlantic
Southbound II We used Herb all the way from Norfolk to Venezuela
Caribbean
Southbound II See above
Caribbean Weather 1230-1300 UTC on
8104 kHz
1300-1400 UTC on
12362 kHz
check-in for subscribers only - details at their Web site
Pacific
Pacific Maritime Net
Russell Radio  0730-0900 on 4445
0830-0915 on 12359
0915-0930 on 12353
1600-1630 on 12353
1630-1645 on 12359
1900-2030 on 4445
operated by Des; times local NZ time; they would like a contribution to track your yacht
0700-0800 on 4417 or 6516
1900-2000 on 4417 or 6516
operated by Ritchie; times local NZ time
Taupo Radio 6224 kHz
Auckland Radio operated by John Goater at 
Tony's Net To Be Supplied.
Australia
Townsville Radio 0603 & 1603 UTC on
2201, 4426,
6507, 8176,
and 12365 kHz. 
Full info in 100 Magic Miles
Brisbane Radio To Be Supplied.
Darwin Radio 0203 & 1203 UTC on
2201, 4426,
6507, 8176 kHz.
0433, 0833 & 2233 UTC
same freq.
Offshore forecasts

Coastal forecasts
Full info in Cruising Guide to SE Asia.
Sydney Radio To Be Supplied.
Indian
No Info yet
Red Sea
No Info yet
Mediterranean
No Info yet

Short Term Predictions

All of the Sources and Delivery Methods for Intermediate Forecasts can be used for Short Term Predictions since they are usually based on current observations.  In addition there are a few extra assets for short term predictions:

  • Direct Download Weatherfax - Polar satellites that circle the earth transmit photographs and infrared imagery as they pass overhead, and this can be received by special VHF receivers connected to a laptop. $US1000 to $2000 can buy a system from Xaxero or OCENS
  • Direct Observation - By noting wind direction and speed plus cloud formation a reasonable prediction for the next 6 to 12 hours can be made.  Use the guidance in
 
 

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