Irma's warning, María's blow

Hurricane Irma passed near Puerto Rico around September 6, 2017. It never made a direct landfall on the island, but none was needed: the storm still left about a million residents without power, a preview of grid vulnerability no one yet knew was about to be tested far harder.

Two weeks later, Hurricane María struck directly. It made landfall just south of Yabucoa on September 20, 2017, as a high-end Category 4, after reaching Category 5 offshore with sustained winds of 175 mph and a central pressure of 908 millibars. María was the strongest hurricane to hit Puerto Rico in nearly 90 years, and the difference between Irma's near pass and María's direct landfall turned out to be the difference between a bad storm and a catastrophe.

Damage estimates run to roughly $90 to $92 billion, almost all of it concentrated in Puerto Rico, placing María among the costliest hurricanes on record. The storm knocked out electricity across the entire island and much of its water system at the same time. The blackout that followed stretched well into 2018, and is often cited as the longest blackout in U.S. history: not days or weeks, but months, for large parts of the island.

What made María the worst natural disaster in Puerto Rico's modern history was not just the wind speed or the dollar figure. It was the combination: a grid already strained by years of deferred maintenance and a debt crisis that had left public infrastructure under-invested, struck by the strongest storm in nearly a century, on an island still recovering from Irma two weeks earlier. The consequences of that combination — including how many people the storm really killed — would take Puerto Rico nearly a year to begin reckoning with fully, a story this blog takes up next.

Sources: Huracan Maria; Efectos del huracan Maria en Puerto Rico. Freeze 2026-08-22.