A downgraded Hanna continued charging across the borderland of South Texas and northeastern Mexico, where flooding remained the biggest threat Monday in a region that was already reeling from a surge in cases of the coronavirus.

Also, Hurricane Douglas gained some strength and began to spin away from many of the Hawaiian Islands as it skirted the state late Sunday.

Hanna, downgraded to a tropical depression, passed over the U.S.-Mexico border Sunday with winds near 50 mph, the National Hurricane Center said. It unloaded more than 12 inches of rain in some areas, and more was expected.

Border communities whose health care systems were already strained by COVID-19 cases — with some patients being airlifted to larger cities — found themselves grappling with Hanna. There were no immediate reports of any deaths on either side of the border.

Henry Van De Putte, CEO of the Red Cross’ Texas Gulf Coast chapter, said the organization would open more shelters with reduced capacity to ensure social distancing. Volunteers and people seeking refuge will undergo temperature checks, and a medical professional will be assigned to each location, he said.

Coastal states scrambled this spring to adjust emergency hurricane plans to account for the virus, and Hanna was the first big test. Gov. Greg Abbott said Saturday that some people in need of shelter would be given hotel rooms to keep them apart from others.

Abbott announced Sunday that the Federal Emergency Management Agency approved an emergency declaration that will provide federal aid.

Hanna blew ashore as a Category 1 storm late Saturday afternoon with winds of 90 mph not far from Port Mansfield, which is about 130 miles south of Corpus Christi.

More than 150,000 customers lost power Sunday throughout South Texas, including Corpus Christi, Harlingen and Brownsville, utility officials said.

Corpus Christi is in Nueces County, where 60 babies tested positive for COVID-19 from July 1 to July 16. Farther south in Cameron County, more than 300 new cases have been reported almost daily for the past two weeks. The past week has also been the county's deadliest of the pandemic.

Hanna came nearly three years after Hurricane Harvey blew ashore northeast of Corpus Christi. Hanna was not expected to be as destructive as Harvey, which killed 68 people and caused an estimated $125 billion in damage in Texas.

Hurricane Douglas gained some strength and began to spin away from many of the Hawaiian Islands as it skirted the state late Sunday.

Forecasters said a hurricane warning was canceled for Oahu but remained in effect for Kauai County, including the islands of Kauai and Niihau, which could still be hit by the system with strong wind gusts and rough surf.

“It’s still not out of the realm of possibilities. So we want people to really remain vigilant and stay prepared, at least for tonight,” Eric Lau, a meteorologist with the National Weather Service in Honolulu said Sunday.

Late Sunday, Douglas was 100 miles northwest of Honolulu. It had maximum sustained winds of 90 mph, making it a Category 1 hurricane.

Heavy rain and wind gusts battered Maui during the morning, downing a small tree on the Hana Highway.

Gentle rain fell and blustery winds swayed trees on Oahu, home to the state’s biggest city, Honolulu. Sand and debris washed ashore on a two-lane coastal road.

Despite the dangers, surfers rode waves and residents took selfies at a lookout point next to the ocean.

Lau said Douglas would have been a lot worse had its track been 20 or 30 miles to the south.

One reason is that this path put Douglas to the north of the state and not directly over the islands. Another is that this path mostly put the island chain near the southwest quadrant of the storm, which is often less destructive than the northeast and the right side of a hurricane’s eye, Lau said.

“We were really playing with a really fine line, a razor thin line between what we’ve experienced today compared to what we could have experienced,” he said.

About 300 people evacuated to the Hawaii Convention Center on the edge of Waikiki. On Maui, 22 people were at five shelters around the island.

Evacuees were told to bring masks and hand sanitizer along with the usual emergency supplies of food and water. People will have to wear face coverings to be admitted, and will have to wear them unless they are eating, drinking or sleeping.

State health department officials contacted each of the 625 people who were currently in isolation or quarantine as of Friday because they are either COVID-19 positive or have been in contact with someone who is. Every one of those indicated they would shelter-in-place and not seek refuge at a hurricane shelter.

Hawaii has some of the lowest coronavirus infection rates in the nation, but COVID-19 numbers have been rising in recent weeks. For three consecutive days through Saturday, Hawaii reported record highs of newly confirmed cases.

President Donald Trump issued an emergency declaration for Hawaii because of the hurricane, directing federal assistance to supplement state and local response efforts.

Hawaiian Airlines canceled all Sunday flights between Hawaii and the U.S. mainland and also between the islands.

Rainfall was expected to be between 3 to 6 inches with locally higher amounts possible.