It's been a sweltering summer for much of the US, with temperatures reaching new highs seemingly every day. And along the Gulf Coast, officials are now grappling with how to handle two potentially deadly disasters set to compound: a hurricane and extreme heat.

In New Orleans, this summer was the first time officials were forced to tap into their "rainy day" fund, which is typically meant for hurricane emergency response, to address heat emergencies.

"It's really a new frontier for us," Anna Nguyen, public information officer for New Orleans Homeland Security Emergency Preparedness, told CNN.

Last week, the city issued an emergency declaration for extreme heat, underscoring rising concerns about widespread power outages ahead of peak hurricane season. Without air conditioning and sufficient shelter capacity, the cascading effects of these dual disasters could be deadly for the most vulnerable people.

Hazards indirectly related to storms, like exposure to heat, kill nearly as many people as the storm itself, NOAA data shows. Nearly 22% of those so-called indirect deaths were caused by heat and generator misuse from 2013 to 2022. Experts have also said that extreme heat is a silent killer and can be a major contributing factor in the overall hurricane death toll.

Emergency response officials in major urban areas like Miami-Dade County, New Orleans and Houston — places that have endured blistering temperatures this summer — told CNN that they've had to rethink extreme weather.

"Climate change is functioning as a threat multiplier, and we're seeing more and more often dual threats happening at once," Christopher Dalbom, assistant director at the Tulane Center for Environmental Law, told CNN. "Anybody who's been without power during hurricane season in the Gulf knows that even without an official emergency declaration for excessive heat, it gets pretty excessive."

Cascading effects

The Gulf Coast is no stranger to hurricanes, but consecutive days with temperatures over 100 degrees Fahrenheit are a new experience for many.

An intense hurricane and extreme heat could be a deadly combination because storm destruction and widespread power outages would leave people exposed and vulnerable to heat, said Nikisha Williams, managing director of collective impact at The Miami Foundation.

"If Miami experienced extreme heat at the same time, portions of our community would have no relief for what could be days or weeks," Williams told CNN. "This is extremely dangerous for the most vulnerable populations such as children and the elderly."

When Hurricane Irma pummeled Florida in 2017, for instance, several people were killed at a Hollywood nursing home due to overheating after the storm knocked out the air conditioning.

Texas is no different. Over the past few years, Houston has endured devastating hurricanes, a deadly winter freeze, drought, forest fires and now oppressive heat. Officials there are still navigating how to properly prepare for the rapidly changing extreme weather to avoid mass casualties.

"Climate change has really been a huge eye-opener for us," Thomas Muñoz, emergency management coordinator for Houston's Office of Emergency Management, told CNN. "It's so unpredictable now, I can say that. We've never seen record-breaking days like this."

With dozens of record-high temperatures being set across Florida since the start of June, coupled with brutal humidity that has made the heat even more dangerous, Miami-Dade County officials have been scrambling to prepare for the day that extreme heat might combine with a landfalling hurricane.

Pete Gomez, director of emergency management in Miami-Dade County, said the county has been ramping up emergency management and disaster recovery efforts, especially when it comes to addressing both storm threats and extreme heat.

In 2021, Miami-Dade County Mayor Daniella Levine Cava appointed the nation's first ever chief heat officer with the goal of raising the public's awareness about the dangers of extreme heat to the same level as hurricanes.

Since then, she has expanded initiatives to prepare for a dual-disaster scenario. The county was able to secure funding to install air conditioning units in some affordable housing that did not have any. Gomez said all shelters have backup generator systems to keep residents cool, and they've also established relationships with the county's homeless trust and nonprofit groups, including The Miami Foundation.

"That's the revision we need so we can meet the needs of the community," Gomez said. "Part of that need is preparedness, getting the message out, and making sure that everything is done to try to minimize the impact of these events as much as possible."

But Williams, who was born and raised in Miami, said the county is still not fully prepared due to rapidly changing demographics and the need for more widespread messaging and education on living in a region prone to climate disasters.

"I feel like I'm betraying my city, but the reality is we're not prepared," she said. "Every storm brings something incredibly different if I'm being honest. There's always something new that we didn't think of. And so, even in the best of situations, we probably will not be 100% prepared."

"But I think we are more prepared today than we were before," Williams added.

Lessons learned

Emergency management officials from New Orleans and Houston say they are well-equipped and prepared for both disasters to happen, despite the unprecedented nature of how climate change has recently been taking shape.

In Houston, Muñoz said they have expanded their outreach, including revising messaging about resources available in the event of a disaster. They are not only deploying more languages like American sign language to accommodate the city's diverse population, but they are also fostering partnerships with nonprofit groups and grassroots organizations.

"The best thing for us that I've learned is just that constant communication with people throughout the year and then when we start the process of seeing something, we do a lot of calling like what do y'all need? What I do we have issues?" Muñoz said. "It's like we are constantly looking at the what ifs and then we work towards that, and of course, we capture the lessons learned and how we can do better."

For New Orleans, Nguyen said that they're continuously taking what they have learned from previous storms and are translating it to heat emergencies. Since Hurricane Katrina, she said officials have built robust relationships with the community in order to work toward preparedness and quick recovery.

"New Orleans has been battle-tested," Nguyen said. "There's always going to be room for improvement, that's the nature of this work — you can always do things better, but it's how do we take lessons learned and apply it to what's in front of us now."