Natural disasters like hurricanes Harvey and Irma can displace people and leave them scrambling to find stability and routine.

But during catastrophes, victims of domestic violence face a unique challenge: seeking safety from their abusers.

Most evacuees are seeking shelter but domestic violence survivors face a “double whammy” of escaping the danger of their abuser and finding safety from the looming disaster, said Ruth Glenn, the executive director of the National Coalition Against Domestic Violence.

Disasters leave physical and social environments in disarray and are likely to increase any person’s or family’s vulnerability to violence, according to the World Health Organization.

Loss of property, inadequate food and water, unraveling social networks and loss of income heighten stress during disasters, which can leave domestic abuse victims particularly vulnerable, the W.H.O. said.

These times of upheaval make it difficult to collect data to compare instances of domestic violence, but the data that exists suggests that natural disasters might spur an uptick in domestic and sexual violence and child abuse.

“Isolation, safety, resources and housing: Those are the things that are exacerbated by a storm for these victims,” said Pamela Jenkins, a professor at the University of New Orleans who has researched violence against women, disasters and community response, particularly in the aftermath of Hurricane Katrina.

During and after a disaster, it can be more challenging for these women to obtain services and aid. Domestic violence hotlines may be disconnected, and emergency responders can be overwhelmed, sometimes leaving abuse victims to fend for themselves. That, in turn, can lead them to return to or remain with their abuser.

If people evacuate with their abuser, they may find themselves cut off from resources, such as family, friends and neighbors who have been helping them, said Brenda D. Phillips, the associate dean of Ohio University Chillicothe where she oversees its emergency response training center.

“When you’re trying to rescue lives, domestic violence remains that hidden thing,” she added.

A 2010 report from the Centers for Disease Control and Prevention said approximately 42 million women in the United States have experienced rape, physical violence and/or stalking by an intimate partner in their lifetime.

The Bureau of Justice Statistics reported in 2006 that 30 percent of female homicide victims were murdered by their intimate partners — compared with 5 percent of male homicide victims — but other analyses put it at as much as 50 percent.

In the aftermath of disasters, financial help can sometimes go to the abuser, further oppressing the victim, Ms. Phillips said.

“If an aid agency cuts a check to the family, who controls that check?” she asked. “And if you’ve lost your home, and the shelter is now destroyed, and your abuser has the check, and you’re displaced from your family and friends because you’re halfway across the state or country now, you’re really in a difficult situation.”

The Louisiana Coalition Against Domestic Violence reported that after Katrina, women were being assaulted by their partners in emergency shelters.

In the aftermath of Hurricane Andrew around Miami in 1992, spousal abuse calls to the local help line increased by 50 percent, and more than one-third of 1,400 surveyed residents reported that someone in their home had lost verbal or physical control in the two months after the hurricane, according to the The Gender and Disaster Network.

Children compound these obstacles, as day care centers and schools shut down. Custody arrangements may also leave victims separated from their children. During Katrina, the criminal court flooded, causing a domino effect of delays.

The W.H.O. said there was evidence that child abuse also increases after a natural disaster.

In the six months after Hurricane Floyd hit North Carolina in 1999, the rate of traumatic brain injury, one of the most severe results of child abuse, in children under two years old saw a fivefold increase in counties that were severely affected by the hurricane. There was no increase in counties that were less affected or not affected.

As for what can be done for those in Texas and Florida who may be dealing with these problems, communication and outreach are crucial, Ms. Phillips said.

Domestic violence shelters should leave fliers at emergency shelters to let people know where they can get help, and should broadcast public service announcements, she said.

Those involved in relief efforts should also lean on staff members at domestic violence shelters because “they know what it means to get through with a vulnerable population in a disaster and a daily disaster,” Ms. Jenkins said.