Updated

Four days after Harvey made landfall as the fiercest hurricane to hit the U.S. in 13 years, it was still pounding Southeast Texas with rain. Here are some things happening on the ground:

THE FORECAST

Houston is getting a bit of a break from the relentless rain. Forecasts call for only 2 to 3 inches (5 to 7.5 centimeters) in the Houston area. But torrential rains will continue over other parts of Southeast Texas and southwestern Louisiana. Harvey is drifting over the Gulf of Mexico, but is expected to turn back onto land Wednesday morning, probably in southwestern Louisiana. Meanwhile, the storm could creep eastward as far as Mississippi by Thursday, meaning New Orleans is in Harvey's path.

While Harvey made landfall as a Category 4 hurricane on Friday, it quickly lost strength to become a tropical storm that's sat over the Texas coast. That's meant rain, not wind, have been the primary concerns. Harvey has dumped amounts of rain that are so unprecedented that the National Weather Service had to update its color charts on its official rainfall maps.

A TEST FOR TRUMP

President Donald Trump will visit Texas Tuesday. Harvey poses a significant test for the White House, which has largely been mired in crisis of its own making during Trump's first seven months in office. Trump promised Texas residents will "have what you need" and that federal funding will come "fast."

Trump is headed to Corpus Christi , where he'll observe the federal government's efforts to help and get briefings from local leaders and organizations. He'll then go to Austin, the state capital, and will meet with state officials.

CONVENTION CENTER SHELTER

Houston set up the George R. Brown Convention Center as a shelter on Sunday, and it's quickly filled up with people who escaped rising floodwaters in their homes. The second night inside the convention center was louder, more crowded and at times, more chaotic. More than 9,000 people are in the center — almost double its capacity of 5,000. Volunteers pushed cots together to make space on the floor. Some people are laying out towels, blankets and strips of cardboard. The demand on the convention center is expected to grow, and city officials are considering opening more.

FLOOD INSURANCE

One problem for people whose homes are under water from Harvey is insurance . Experts say only a small fraction of homeowners in Harvey's path of destruction have flood insurance. Homeowners insurance typically covers just damage from winds, not flood, and much of the damage in Houston is from flooding, not winds. That means families with flooded basements, soaked furniture and water-damaged walls will have to dig deep into their pockets or take on more debt to fix up their homes. Some may end up leaving their communities.

PUTTING IT IN PERSPECTIVE

How much rain has fallen? Consider this: Already, 15 trillion gallons (57 trillion liters) of rain have fallen, and an additional 5 trillion or 6 trillion gallons (19 to 23 trillion liters) are forecast by the end of Wednesday, meteorologist Ryan Maue of WeatherBell Analytics calculates. That's enough water to fill all the NFL and Division 1 college football stadiums more than 100 times over.

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