From the Ocean Navigator School of Seamanship weather course A comma cloud system is really nothing more than a more descriptive name for a cyclone or low-pressure system. Learning to recognize the elements of the comma cloud will help voyagers when they’re studying satellite images and weather charts. In general, a comma cloud is a deep mass of multilayered clouds that is often shaped 1ike a comma. It reflects a region of positive vorticity advection (PVA) and can vary in size from a few hundred miles (a clump of thunderstorms whose anvils combine in the shape of a comma) to…
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In the last newsletter I speculated on the possible retirement of hurricane names over the past two Atlantic hurricane seasons. Recall that it is the World Meteorological Organization (WMO) that generates the lists of names that are used for tropical cyclones around the world, and because of the Covid-19 pandemic, they had been unable to meet after the 2019 hurricane season to decide which names should be retired from the list because the storms were particularly impactful in terms of property damage and/or loss of life. The WMO committee in charge of this task finally met (virtually) in March of…
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The 2020 hurricane season was one for the history books. For just the second time in modern times, the list of Atlantic storm names was exhausted, requiring the use of the Greek alphabet. The last time this happened was in 2005, which was the year of Katrina. In that year, storm names extended six deep into the Greek alphabet, with the final storm that year having the name “Zeta”. For the 2020 season, the names went all the way to Iota (the ninth letter of the Greek alphabet). The final storm advisory for the 2020 season was issued on November…
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By the numbers

Long before the advent of electronics and high tech wind measuring devices, a qualitative wind estimating method called the Beaufort Scale of Wind Forces was used. It was invented by an early English navigator by the name of Francis Beaufort (1774 to 1857) who wanted to correlate ships' log reports of wind speed with the ensuing action taken by the ships' skippers to set the proper amount of sail on the square riggers. Too little sail and the ship was not combat ready; too much sail and the ship risked having its sticks blown out. His scale ranged from 1…
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