Tropical Storm Zeta strengthened into a hurricane on Monday (Oct 26) and was expected to bring torrential rains to the Yucatán region of Mexico, offering further evidence that not only has this hurricane season been extremely active, it's also been extremely wet.
Zeta is the 27th named storm of the season and the season is far from over: Storms could continue to form for another five weeks, and possibly longer.
That is one shy of the record set in 2005, when 28 storms grew strong enough to warrant names.
The National Weather Service said Zeta could dump up to a foot of rain on some parts of the Yucatán by Tuesday.
The storm was then expected to cross the Gulf of Mexico and hit the United States, where the forecast was for up to 15.2cm of rain in the coastal Gulf States.
If the forecasts hold, Zeta will continue a pattern that has been playing out this year where much of the damage from storms has come not from wind but from water. And that destructiveness is linked to climate change.
Of the 27 named storms so far in 2020, only four have been major hurricanes, rated Category 3 or higher. (In 2005 there were seven major hurricanes, also a record.)
Seventeen of 2020's storms never got above tropical storm strength, with winds below 117.4kmh, but heavy rains accompanied several of them, starting with Tropical Storm Bertha, which brought 35.6cm of rain to parts of South Florida in late May.
All tropical cyclones pick up moisture as they develop and travel across the ocean. But global warming has raised average air temperatures, and warmer air holds more moisture.
Studies of specific storms, including Hurricane Harvey, which brought 1.2m or more of rain to the Houston area in August 2017, have found them to be affected by human-induced climate change.
Zeta was travelling at a fairly typical speed of about 16kmh on Monday, and was expected to speed up as it approached the United States.