Subtropical Storm Forms Near Bermuda, 2019 Hurricane Season Starts in May. (Again.)

Subtropical Storm Andrea formed southwest of Bermuda on Monday. The appearance of a named storm in the Atlantic means this basin’s hurricane season has started before June 1 for the seventh time in the last decade. Andrea will be weak and short-lived, posing no threat to land.

This storm forming while everyone is paying attention to the severe weather over the Plains is the atmospheric equivalent of a Friday night news dump. Most people will never know it existed, and the rest will forget about it soon enough. Subtropical Storm Andrea will probably dissipate by early Wednesday morning without affecting land. The storm’s remnants could bring showers to Bermuda by the middle of the week, but that’s about it as far as impacts are concerned.

A subtropical storm is a low-pressure system that shares both tropical and extratropical characteristics. It’s tropical-like. It forms and acts like a tropical cyclone, and carries the same impacts as a tropical cyclone, but it’s not fully warm throughout the system and it derives some of its energy from upper-level winds. A fully tropical cyclone would be warm from top to bottom and the thunderstorms near the center of the storm would completely drive its formation and maintenance.

We’re almost to the point where you can wager money on a named storm forming before June 1 and wind up winning the bet. This is the seventh hurricane season since 2009, and the fifth season in a row, that we’ve seen at least one named storm form in the “pre-season.”

I argued a few weeks ago that we should move the beginning of the Atlantic hurricane season up a few weeks into May. Not only would moving up the start of the season to, say, May 15, which would sync it up with eastern Pacific’s season, but it would start the awareness campaigns a little earlier than they run right now. That’d be helpful for coastal residents, seeing as several of these “pre-season” storms, like Alberto in 2018, wound up making landfall in the United States.

The tropics should fall quiet again for a while after Andrea dissipates.

[Top Image: RAMMB/CIRA]

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