Year 10 Day 99 The Danger Of Long Term Weather Forecasts
06 May 2017 | Simpson Bay Marina, Cole Bay, Sint Maarten
Dave/Mostly Sunny
We have been keeping a sharp eye on weather now for about 10 years. This is because the weather plays a dominant role in our lives; much more now that we live on a boat. When we lived on land, we would at times listen to or watch a weather report just to decide if we should take an umbrella with us when we went out. In other words, our focus was on the "now" aspect of the weather, not the weather in a few days.
For each passage we make, whether is it a short passage or a very long passage, we watch the weather and research very carefully what the various models that we use are indicating that the weather should be during the time of our passage. If things look dicey, we stay put as sailing in heavy weather is just not fun.
Even though we have sailed around the world and have had our share of heavy weather, we consider ourselves as "fair weather sailors". We have seen a number of cruisers take off for a destination while we stay put because our tolerance of bad weather is much less than theirs. Our attitude is that heavy weather puts much more stress on the many components that make up a boat and if just one of those components breaks due to heavy weather, that puts us at risk. In our opinion, potential heavy weather is just not worth the risk and it is something to avoid if at all possible.
The problem we face with researching the weather for longer passages is that the state of the art of weather models is still not where we would like it to be. The atmosphere is just too dynamic for the models that NOAA or Met or any other governmental entities use for making forecasts beyond 3 to 5 days. It fact, there are many places in the world that we have sailed through where the atmosphere is so unstable that weather models fail to accurately forecast weather beyond 6 to 8 hours. These include the South Pacific Convergence Zone (roughly between Bora Bora and Papua New Guinea) and the Mozambique Channel which runs between Madagascar and South Africa. In both of these most unstable areas, we repeatedly got nailed by heavy weather as the "weather windows" collapsed just hours after we started our passages.
This lack of good long range weather forecasting is what we are now facing as we keep an eye out for what the weather will be during our upcoming passage from Sint Maarten to the Azores. To prove my point, I am posting to this blog the latest model result of the weather patterns for the North Atlantic for May 13th. Above this blog, I am also posting the photo of the May 13th forecast that I posted with our May 4th blog. What a difference! I will be watching the May 13th forecast each day going forward and posting it just to show you how it may change as we get closer and closer to that date. I suspect that the closer we get to May 13th, the forecast will improve in its accuracy.