Tropical Storm Martin formed over the central North Atlantic on Tuesday, becoming the 13th named storm of the 2022 Atlantic hurricane season and the second to form in two days.
The storm was about 885km east-northeast of Bermuda, the National Hurricane Centre said. It was moving east at 19kmh and was not an immediate risk to land.
Tropical Storm Lisa, meanwhile, was moving west across the western Caribbean and was expected to strengthen on Tuesday as it passed south of the Cayman Islands in the western Caribbean Sea, before reaching hurricane status on Wednesday.
A storm is given a name after it reaches wind speeds of at least 62kmh.
The Atlantic hurricane season, which runs from June through the end of November, had a relatively quiet start, with only three named storms before Sept 1 and none during August, the first time that has happened since 1997.
Storm activity picked up in early September with Danielle and Earl, which formed within a day of each other.
By the end of September, Hurricane Ian had slammed into the coast of Florida as a Category 4 hurricane, one of the most powerful storms to hit the United States in the past decade.
In early August, scientists at the National Oceanic and Atmospheric Administration issued an updated forecast for the rest of the season, which still called for an above-normal level of activity.
In it, they predicted the season could see 14 to 20 named storms, with six to 10 turning into hurricanes that sustain winds of at least 119kmh.
Last year, there were 21 named storms, after a record-breaking 30 in 2020.
For the past two years, meteorologists have exhausted the list of names used to identify storms during the Atlantic hurricane season, an occurrence that has happened only one other time, in 2005.
The links between hurricanes and climate change have become clearer with each passing year. Data shows that hurricanes have become stronger worldwide during the past four decades.
A warming planet can expect stronger hurricanes over time, and a higher incidence of the most powerful storms, though the overall number of storms could drop, because factors like stronger wind shear could keep weaker storms from forming.
Hurricanes are also becoming wetter because of more water vapor in the warmer atmosphere; scientists have suggested storms like Hurricane Harvey in 2017 produced far more rain than they would have without the human effects on climate.
Also, rising sea levels are contributing to higher storm surge, the most destructive element of tropical cyclones.