MIAMI, United States (AFP) — Hurricane Harvey has set what forecasters believe is a new rainfall record for the continental United States, officials said Tuesday.

Harvey, swirling for the past few days off Texas and Louisiana — at times as a hurricane and at times a tropical storm — has dumped 51.88 inches (132 centimetres) of rain in Cedar Bayou, a salt water channel on the Texas coast, the National Weather Service said.

“This reading is higher than the previous record of 48 inches set during tropical cyclone Amelia of 1978 at Medina, Texas,” it added.

It was the second record reported in just one day. The first was 49.32 inches measured at a rain gauge southeast of Houston.

NHC spokesman Dennis Feltgen said that record is being treated preliminarily as one for the entire continental United States.

He added that confirming the figure “will take a lot of research,” as experts review water gauges and past historical records — a process likely to take several weeks.

Harvey made landfall in Texas on Friday as a Category Four hurricane. It has since weakened to a tropical storm but is still unleashing massive amounts of rain over Texas and Louisiana.