Sailing through Tropical Waves in Grenada

Hey All, Just a short quick post here from rainy Grenada. I am sitting at an anchorage in Halifax Harbor Grenada drying out from a very rainy day of sailing yesterday. We are on a quite nice Fountaine Pajot 47.

I have been teaching at LtD Sailing in Grenada the last few weeks and as Grenada’s rainy season just started here at 12N, I have had a chance to observe tropical waves first hand as they pass by.

A tropical wave in the Atlantic is generated and sent eastward as trade winds pass over the warmer drier air of the Sahara desert juxtaposed with the lowland rainforests of Nigeria, Ghana, and Guinea.

The temperature differential creates the genesis of anticlockwise bias as the faster hotter north section moves faster than slower moving wetter cooler southern section.

By the time this wave hit the West Indies, we experienced the northern section of the Wave here in Grenada and Cariacou first, and then the southern section hit Trinidad and Tobago, and South America over the following 12-24hrs.

With a tropical wave having it’s velocity biased towards the north, if something were to introduce further rotation for the westerly component of the southern section, commonly caused by a passing or proximal low pressure, these progress to tropical storm.

It is possible to track tropical waves using NHC’s Tropical Surface Analysis and Tropical Discussion products.

You can see the tropical wave that just passed us yesterday in the image above.

You might also notice a low and a tropical wave just west of Panama, keep an eye on that in the coming days to see if it becomes a tropical invest area(area to monitor for tropical storm formation) it may be too close to land to do so, but exemplifies the pattern that would be worth monitoring if noted in more open ocean conditions.