Again fairly strong Northerly winds blow.
The beginning of the day brings an increasing North by East wind. It also brings the watches on deck to unfurl and set sail. Squares to Top Gallants, Lower Staysails, all the headrig and Spanker now give us enough speed in the right direction to switch the engines off and enjoy the close-hauled sailing.
5,6,7kn show up in the wheelhouse computer screen. A good speed to eat away the last 160nm to Tristan da Cunha. But the weather and meteorological pressure systems are capricious too in these lower latitudes and things can change quickly. From a good wind to push us fast to a fair breeze or even light airs. That’s one of the beauties of travelling on a ship like the Europa on a long trip like we are doing. Plans change, schedules too. Chances to visit a set of remote locations along a range of different latitudes, come and go as well.
Today, good strong northerlies, forecast for tomorrow: they come around to a light Southeasterly and decrease.
For the moment we sail as close to the wind as we can on a course towards Tristan, pitching and heeling to starboard with occasional large waves hitting Europa’s hull.
Several squalls pass by today, at times more frequently and loaded with rain and gusts. It seems also that the general wind starts to pick up before midday, a combination that makes for dousing and furling the Top gallants first, and as conditions keep building up over lunch, soon after the Outer Jib comes down.
At night the ship sails into areas of even more squall activity. It can happen that during the dark and colder hours, the air cools rapidly while the ocean temperature remains pretty much the same. The ocean surface warmer than the air just above it, the conditions necessary to start squall activity.
Then the radar shows several clouds on their own around us first, then they tend to line up. Both size and intensity of the shower can be estimated by the amount of clutter and physical size of the radar return.
Besides seeing them as a clear signal on the radar, the passage of the squall line revealed itself first with a drop in the temperature (actually welcomed tonight to relieve a bit from the warm day), and a short period of gusty winds followed by falling rain.
The latitudes where we find ourselves, lower and much warmer than the windier 40’s to 60’s, are well known for the development of squalls. They grow due to the atmospheric instabilities, rising and falling of warm and cold air, and frontal passages or boundary layers between high and low pressure systems, especially cold fronts.