Tropical Storm Nicholas strengthened as it headed for the Gulf Coast on Sunday, threatening heavy rain and floods in coastal areas of Texas, Mexico and Louisiana.

Forecasters at the National Hurricane Center in Miami said tropical storm warnings were issued for coastal Texas and the northeast coast of Mexico. Nicholas is expected to produce total rainfall of 5 to 10 inches (13 to 25 centimeters), with isolated maximum amounts of 15 inches, across portions of coastal Texas into southwest Louisiana on Sunday through midweek.

The storm was expected to bring the heaviest rainfall west of where Hurricane Ida slammed into Louisiana two weeks ago. Although forecasters did not expect Louisiana to suffer from strong winds again, meteorologist Bob Henson at Yale Climate Connections predicted rainfall could still plague places where the hurricane toppled homes, paralyzed electrical and water infrastructure and left at least 26 people dead.

“There could be several inches of rain across southeast Louisiana, where Ida struck,” Henson said in an email.

Across Louisiana, 140,198 customers — or about 6.3% of the state — remained without power on Sunday morning, according to the Louisiana Public Service Commission.

Louisiana Gov. John Bel Edwards took to Twitter to urge people in the southern portion of the state to keep a close eye on the storm and be prepared for heavy rains and flash flooding.

The storm is projected to move slowly up the coastland which could dump torrential amounts of rain over several days, said meteorologist Donald Jones of the National Weather Service in Lake Charles, La.

“Heavy rain, flash flooding appears to be the biggest threat across our region,” he said in an email.

The storm has the potential to dump as much as 15 to 25 inches (38 to 64 centimeters) of rain in isolated areas either in southeast Texas or southwest Louisiana, he said.

At 2 p.m. EDT, the storm was located about 180 miles (285 kilometers) northeast of Veracruz, Mexico and 310 miles (500 kilometers) south-southeast of the mouth of the Rio Grande River. Its maximum sustained winds were clocked at 40 mph (65 kph) and it was moving north-northwest at 15 mph (24 kph). Gradual strengthening is forecast in the next day or so.

Texas Gov. Greg Abbott placed rescue teams and emergency medical groups on standby along the length of the Texas Gulf Coast.

“We will continue to closely monitor this storm and take all necessary precautions to keep Texans safe,” Abbott said in a statement. “I encourage Texans to follow the guidance and warnings of their local officials and be mindful of potential heavy rain and flooding.”

Colorado State University hurricane researcher Phil Klotzbach said via Twitter that Nicholas is the 14th named storm of 2021 Atlantic hurricane season. Only 4 other years since 1966 have had 14 or more named storms by Sept. 12: 2005, 2011, 2012 and 2020.