ABC News(NEW YORK) — With landfall hours away, Tropical Storm Barry was already lashing the southern coast of Louisiana with wind and heavy rain.Barry is forecast to be a low-end Category 1 hurricane when it comes on shore near Morgan City, Louisiana, Saturday morning. But it is the very heavy rainfall and major flash flooding that will cause the most problems through the weekend.Pete Gaynor, acting administrator of the Federal Emergency Management Agency, told “Good Morning America” Saturday morning that the category of the hurricane is less worrisome that the heavy rainfall the storm will dump on the area.“This is a rain event,” he said, adding that some areas could see as much as 25 inches of rain. “If you haven’t made preparations, it’s probably too late.”He urged those in high-risk areas to heed local officials’ instructions.Gaynor added that federal workers were fanned out throughout the state to assist.“We’re ready to go,” he said.Barry will be one of the biggest tests for the levee system built after Hurricane Katrina in 2005. Gaynor said that FEMA had “high confidence that the levees will performed as designed.”The tropical storm was packing maximum sustained winds of 70 mph as of 7 a.m. local time, with Houma, Louisiana, near the southern coast, already reporting sustained winds of 53 mph.Hurricane warnings, tropical storm warnings, flash flood watches and tropical storm watches have been issued for parts of the Gulf Coast as Barry comes closer to the shoreline.As much as 2 feet of rain is possible in central Louisiana, with heavy rainfall totals stretching well into Mississippi and even Arkansas. The highest totals will be near Morgan City, where it is expected to come ashore later Saturday morning.“We don’t have the pumping capacity to handle 20 inches of rain if it comes at one time,” Morgan City Mayor Frank Grizzaffi told ABC News Friday night.“So we’re hoping that we get some heavy rain, that it stops and lets us catch up, and we’re ready for the next batch,” he added. “But if we get five, six hours in a row that dumps double digits on us then we’re gonna have some water that’s close to houses.”A storm surge warning has been issued along much of the Louisiana coast, including where New Orleans sits on Lake Pontchartrain.“We hope we are going to miss a big storm here, we hope that we have a great afternoon and next week actually, but we know the worst is yet to come over the next 24 to 48 hours,” said Sheriff Joe Lopinto, of Jefferson Parish, which includes the area surrounding New Orleans. “Stay indoors. It appears as though that is happening right now. Thank you for heeding those warnings.”Tens of thousands of customers were without power in Louisiana hours before the storm made landfall.During the day, Barry will continue to bring heavy rain to Louisiana, with some of the rain expanding into parts of Mississippi and Alabama. The most torrential rain will be east of the central circulation, where rainfall rates could be up to 3 inches per hour. Additionally, tornadoes are possible throughout the day and into Saturday night as the bands come ashore.There won’t be much movement overnight into Sunday with heavy rain still falling over southeast Louisiana and southwest Mississippi.“We are very confident in the entire system’s ability to withstand what Tropical Storm Barry may bring us, whether it’s on the river or on the hurricane system,” said Derek Boese, chief administration officer for Flood Protection Authority East, at a press conference Friday night.During the day on Sunday, bands of rain will continue to impact the same areas, as Barry struggles to move northward. The rain will begin to expand northward into Arkansas and southern Tennessee later in the day.There will be widespread rainfall totals of 10 to 20 inches, with locally up to 25 inches in some spots, directly east of the center of the storm. That much rain will lead to dangerous, life-threatening and possibly disastrous flooding.“Jefferson Parish is prepared, we are ready and we will do everything in our power to recover from this event as quickly as possible no matter what happens,” said Jefferson Parish President Michael Yenni.Two years ago, torrential rain fed from tropical moisture caused 20 to 30 inches of rain in southern Louisiana. The massive totals, similar to what is expected this weekend, led to 13 deaths in the state.Copyright © 2019, ABC Radio. All rights reserved.