hotumn noun [C]
UK /ˈhɔː.təm/ US /ˈhɑː.tᵊm/
an autumn where the temperatures are warmer than usual for the season, thought to be at least partly caused by climate change

100-degree October temperatures? Welcome to ‘hotumn.’ We’re in the middle of a new, climate-changed kind of fall — one where you ask for that pumpkin spice latte iced, please … Scientists caution against attributing this year’s sweltering Sweatember and Hottober temps to climate change alone, but the long-term trend is clear: This certainly won’t be our last hotumn.
[grist.org, 25 October 2017]

bombogenesis noun [U]
UK /ˌbɒmb.əʊ.ˈdʒen.ə.sɪs/ US /ˌbɑːmb.oʊ.ˈdʒen.ə.sɪs/
the process by which a storm very quickly becomes more severe because of a sudden drop in atmospheric pressure

The eastern coast has experienced bombogenesis in the past, like the Superstorm of 1993, which is best known for a snowfall that covered parts of Alabama and went all the way to Maine. The NWS ranked it as “among the deadliest and most costly weather events of the 20th Century”.
[www.euronews.com, 3 January 2018]

supercell noun [C]
UK /ˈsuː.pə.sel/ US /ˈsuː.pɚ.sel/
a type of severe thunderstorm in which a column of rotating air is sucked upwards, and is usually accompanied by extreme weather conditions such as very heavy rain or hailstones

A frightening picture taken in Newcastle during the huge storms in June 2012 showed what was believed to be the North East’s first taste of a supercell. The freak storm caused flash flooding across the city, closed the Tyne Tunnel and left over 23,000 homes without power. Now five years later, it is feared one could strike again in our region.
[www.chroniclelive.co.uk, 21 June 2017]

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