Hundreds of thousands of homes and businesses have been without power since Beryl swept ashore Monday as a Category 1 hurricane. Although outages peaked at 2.7 million customers and the Houston area’s main utility, CenterPoint Energy, said it had restored power to about 1.4 million by Friday morning, up to half a million others were expected to be without electricity into next week, with temperatures hovering around 90 degrees (32.2 Celsius) or higher.

Houston-area hospitals have reported about twice the number of emergency room patients as they typically would. More than 320 patients suffered from heat-related illnesses, about triple the norm at this time of year, according to the Houston Office of Emergency Management.

Dr. Ben Saldana, who oversees the 18 emergency rooms in the Houston Methodist hospital system, said his ERs are treating their highest numbers of patients since the widespread power outages during a 2021 freeze, with heat exhaustion and heat-related problems the biggest reasons.

“These range from cramps to heat stroke with (body) temperatures at 104 degrees (40 degrees Celsius),” Saldana said.

The heat also exacerbates chronic problems for people with lung, heart and kidney disease, he said. Kidney patients are also coming in for dialysis because their regular centers are closed, as are patients who rely on oxygen tanks at home but don’t have power.

Beryl has been blamed for at least nine deaths in the U.S. 11 others in the Caribbean. Most of the Texas power outages were caused by downed trees and branches toppling power lines.

The heat and humidity that have blanketed Houston, the nation’s fourth-largest city, since Monday, have angered residents who are eager for a return to a sense of normalcy.

City and state officials set up community cooling centers, but many affected residents have had no easy way to cool off, whether they are trying to tough it out at home or trying to clear debris from their property.

Rain showers briefly cooled things off Thursday, but the National Weather Service issued a heat advisory for Friday with potentially “dangerous” conditions for those without air conditioning. Temperatures were expected to remain in the low 90s throughout the weekend.

The Houston area has dealt with several major storms over the past two decades and the inevitable power outages that follow. As recently as May, storms killed eight people and left nearly a million customers in the dark.

The frequent major storms have led many to invest in home generators, but those carry the risk of causing accidental carbon monoxide poisoning if they aren’t used properly. A common mistake is to run one inside an attached garage, or near an open window or air conditioning vent, which which can cause the odorless, poisonous fumes to seep into a home undetected and kill.

Houston emergency management officials have reported about 120 patients with carbon monoxide poisoning, which is rare except during long power outages.

“This wasn’t as big a problem five or 10 years ago,” said Dr. David Persse, Houston’s chief medical officer.

Nim Kidd, chief of the Texas Division of Emergency Management, urged residents to avoid what he called “preventable deaths” from accidental poisoning.

“If you are running a generator, please be sure it is far away from the area that you’re living and sleeping,” Kidd said.

Houston hospitals also faced problems this week with discharging people who had damaged homes or now power. Officials set up a center at the sports complex where the NFL’s Houston Texans play to hold some of them. More than 60 were there Friday.

At some hospitals, staff reported incidents of families trying to camp out in a patients’ room if they had no power at home. That sort of crowding can create tension and conflicts with staff, Persse said. In one case, a man threw a chair at a nurse who wanted a family to leave.

“There are four or five family members visiting Uncle Dave who just had his appendix removed or whatever,” Persee said. “But they are staying 24 hours because their home doesn’t have any power. So not only are you having to deal with the patient, but you are dealing with their entire family.”