11/24/2023
🇬🇧 Southern Ocean Low Pressure Systems Carousel 👇
Several boats have been reporting strong winds and their first taste of navigation within the Southern Ocean low pressure systems. The good news is that it will mean fast sailing and little chance of being stuck in windless areas. The bad news is that it is relentless, merciless and exhausting. Every low pressure, in the southern hemisphere is anticipated by northerly winds, rotating anticlockwise to north westerlies after the warm front, which is wet and miserable like a summer day in Ireland but not violent or stormy. It’s the cold front that follows that brings a ninety degrees wind shift which can occur very suddenly and brings an unstable mass of cold air that blow up from Antarctica. The sea state gets very very messy, with cross seas, gusty winds, chance of breaking waves, squalls, freezing rain; until the cold front blows over and the sky cracks showing some blue tiles behind the gray layer of clouds. Things improve and the sun may even come out briefly, as the wind shifts back to northerly the temperature rises quickly.
Unfortunately, northerlies simply mean that the repeat button has been pushed. Another low is approaching. Interestingly and especially on the approach to Australia there can be some high pressure systems which are much lower than you’d expect in the Southern Ocean. We associate highs with good weather, unfortunately these highs often bring headwinds if dipping south is not an option due to the Ice Limit. The high pressures can also block the movement of the low pressures, creating funnels of strong winds squeezing between a semi-stationary high and an approaching low as we can see on the right of this snapshot. Skippers please hold on tight on tight to your plastic race horses, the carousel is about to start.
https://globalsolochallenge.com/southern-ocean-low-pressure-systems-carousel/