Alex is the first Atlantic hurricane to form in January since 1938.

For the first time on record in January, the National Hurricane Center issued advisories for active tropical cyclones. Alex became the first named tropical weather system to form in the Atlantic during January since 1978. It was classified as a subtropical storm, one that exhibits a combination of tropical and non-tropical characteristics. Alex became the first named Atlantic storm almost six months ahead of average, which is on July 9. In 2015, the first named storm, Ana, — which was also classified as subtropical — formed on May 7. Historically, only 0.5 percent of tropical storm activity has occurred prior to June 1.

“Alex is only the fourth known named storm to form in this month in the historical record that begins in 1851,” the National Hurricane Center wrote Wednesday. The National Hurricane Center seemed stunned by Alex’s strength in its 10 a.m. discussion, writing: “Remarkably, Alex has undergone the transformation into a hurricane. A distinct eye is present, embedded within a fairly symmetric mass of deep convection.” 

Alex has steadily strengthened over the past day and is making history as an extraordinarily rare January hurricane. The National Hurricane Center says Alex is the first Atlantic hurricane to form in January since 1938.  The storm has peak winds of 85 mph, just about 5 mph shy of the 1938 January hurricane, the strongest on record for the month.

Positioned 490 miles south of the Azores, Alex is making a beeline toward the group of islands that sit about 900 miles west of Portugal. The Azores government has issued hurricane warnings for the most of the islands. Only 10 hurricanes on record have tracked within 200 miles of the Azores, all in August or September. “Alex is in a rare spot for September, much less January,” tweeted Eric Blake, a forecaster at the National Hurricane Center. “It is only the 2nd hurricane on record to form north of 30N (latitude) east of 30W (longitude).”

Alex has strengthened over waters that are usually not warm enough to support hurricane activity. However, the contrast between the surface waters and unusually cold air at high altitudes has created a volatile corridor of air, fostering the storm’s development. “The resulting instability is likely the main factor contributing to the tropical transition and intensification of Alex,” the National Hurricane Center wrote in its 10 a.m. discussion.

While the waters in which Alex has developed are, by themselves, not characteristically warm enough for hurricane formation, they are warmer than normal, helping the storm acquire tropical characteristics, according to Weather Underground meteorologist Jeff Masters. “Between January 8 and 12, pre-Alex tracked generally eastwards over ocean waters that were 22 – 25°C (72 – 77°F); these temperatures were near-record warm for this time of year (about 2 – 4°F above average),” Masters wrote. “These temperatures were just high enough so that Alex was able to gradually gain a warm core.”

Masters added that global warming must be considered as a player in the evolution of Alex. “It is unlikely that Alex would have formed if these waters had been close to normal temperatures for this time of year,” he wrote. “The unusually warm waters for Alex were due, in part, to the high levels of global warming that brought Earth its warmest year on record in 2015. Global warming made Alex’s formation much more likely to occur…”

While Alex spun up in the Atlantic, another highly unusual tropical weather system for the time of year was setting milestones in the Pacific. A storm named Pali reached hurricane intensity in the central Pacific Ocean earlier this week, becoming the earliest hurricane to form in that region on record. Located just 4 degrees in latitude north of the equator, Pali also became the third strongest storm to occur so far south on record in the northwest Pacific basin and the strongest storm to occur so close to the equator in the western hemisphere. Pali’s strength and early formation were also supported by much-warmer-than-normal ocean waters in the Pacific, resulting from both this year’s strong El Nino event and ongoing climate warming.