Tropical Storm Nicholas slowed to a crawl over the Houston area on Tuesday after making landfall as a hurricane, knocking out power to a half-million homes and businesses and dumping more than a foot of rain along an area swamped by Hurricane Harvey in 2017.
Nicholas could stall over storm-battered Louisiana and bring life-threatening floods across the deep south over the coming days, forecasters said.
Nicholas made landfall on the eastern part of the Matagorda Peninsula and was soon downgraded to a tropical storm. It was about 10 miles south-east of Houston, with maximum winds of 45mph as of 10am, according to the National Hurricane Center (NHC) in Miami.
Scientists say damaging storms are becoming more frequent and more intense as part of human-caused climate change. According to Colorado State University hurricane researcher Phil Klotzbach, only four other years since 1966 have had 14 or more named storms by 12 September: 2005, 2011, 2012 and 2020.
Galveston, Texas, saw nearly 14in of rain from Nicholas, while Houston reported more than 6in. That was a fraction of the rainfall during Harvey, which dumped more than 60in over a four-day period.
Nicholas is moving so slowly it will dump several inches of rain as it crawls over Texas and southern Louisiana, meteorologists said. This includes areas already struck by Hurricane Ida and devastated last year by Hurricane Laura. Parts of Louisiana are saturated with nowhere for the extra water to go, so those areas will flood, said University of Miami hurricane researcher Brian McNoldy.
“It’s stuck in a weak steering environment,” McNoldy said. So while the storm itself may weaken “that won’t stop the rain from happening. Whether it’s a tropical storm, tropical depression or post-tropical blob, it’ll still raining a lot and that’s not really good for that area.”
The storm was moving north-north-east at 6mph and the center was expected to move slowly over south-eastern Texas on Tuesday and south-western Louisiana on Wednesday.
More than a half-million homes and businesses lost power in Texas but that number dropped to about 425,000 by late morning, according to the website poweroutage.us. Most outages were caused by winds as the storm moved through overnight, officials said. Across Louisiana, about 98,000 customers remained without power.
Harvey was blamed for at least 68 deaths, including 36 in the Houston area. After Harvey, voters approved the issuance of $2.5bn in bonds to fund flood-control projects, including the widening of bayous. The 181 projects designed to mitigate damage from future storms are at different stages of completion.
McNoldy said Nicholas was bringing far less rain than Harvey.
“It’s not crazy amounts of rain. It isn’t anything like Hurricane Harvey kind of thing with feet of rain,” McNoldy said.
Harvey not only stalled for three days over the same area, it moved a bit back into the Gulf of Mexico, allowing it to recharge with more water. Nicholas won’t do that, McNoldy said.
Nicholas, expected to weaken into a tropical depression by Tuesday night, could dump up to 20in of rain in parts of southern Louisiana. Forecasters said southern Mississippi, southern Alabama and the western Florida Panhandle could see heavy rainfall as well.
The Louisiana governor, John Bel Edwards, declared a state of emergency on Sunday night.