Intense heat and humidity have descended upon parts of Texas, the Gulf Coast, and South Florida this week, signaling an early bout of extreme weather that has experts concerned about the summer ahead. Despite summer officially starting in a month, Miami is already experiencing its hottest May on record.

The heat index in Miami, which measures how hot it feels when humidity and temperature are combined, reached a staggering 112 degrees Fahrenheit over the weekend. This unprecedented heat broke the previous daily record by 11 degrees, according to Brian McNoldy, a senior research associate at the University of Miami. The weekend’s heat index also surpassed Miami’s monthly record by 5 degrees, as noted by McNoldy in a post on X.

“Even if this had occurred in July or August, it would still be remarkable to have two consecutive days with a 112-degree heat index,” McNoldy said. “For any time of the year, that would be extraordinary. But for mid-May, it was completely unprecedented. Not even close.”

Last summer was the hottest on record for Miami and the entire planet. Forecasters predict above-average temperatures for much of the country over the next three months. Additionally, the National Oceanic and Atmospheric Administration (NOAA) recently reported that 2024 is on track to be among the five warmest years in recorded history.

Miami’s recent 112-degree heat index was recorded on both Saturday and Sunday, marking only the second time in the city’s history that there have been consecutive days with such high heat index values, according to McNoldy. The only other occurrence was on August 8 and 9, 2023.

“It’s certainly warmer now than it was at this point in 2023,” McNoldy said. “I don’t know what the rest of 2024 holds, but I hope this isn’t a sign that we’ll break 2023 records.”

In response to the early onset of high heat and humidity, Miami has extended its official heat season from May 1 to October 31 annually. Meanwhile, a heat advisory is in effect across much of South Texas, where temperatures are expected to reach up to 113 degrees in some areas, particularly along the Rio Grande, according to the National Weather Service (NWS).

The NWS has indicated that heat index values between 110 degrees and 120 degrees are anticipated this week, with dangerous heat lingering into the weekend. “As a result, major to extreme risks of heat-related impacts are expected across South Texas,” the weather service stated in its advisory. “Be sure to stay cool, drink plenty of water, and take frequent breaks if you are spending time outside!”

High heat and humidity, including heat indexes around 100 degrees, are also expected in Houston in the coming days. The city is still recovering from last week’s deadly storms, which left tens of thousands of residents without power.

Studies have shown that climate change is increasing the likelihood of early-season heat and fueling more frequent, intense, and longer-lasting heat waves. The consequences can be deadly. Heat kills more people each year in the United States than any other weather disaster, according to the weather service.

This extreme heat poses significant health risks, especially for vulnerable populations such as the elderly, children, and those with preexisting health conditions. Prolonged exposure to high temperatures can lead to heat exhaustion and heatstroke, which require immediate medical attention.

Local governments and health officials are urging residents to take precautions, including staying hydrated, avoiding strenuous activities during peak heat hours, and seeking air-conditioned environments. Community cooling centers are being set up in various locations to provide relief for those without access to adequate cooling at home.

The heat wave is also impacting agriculture and livestock, with farmers and ranchers taking extra measures to protect their crops and animals from the extreme conditions. In urban areas, the heat is exacerbating the urban heat island effect, where concrete and asphalt absorb and retain heat, making cities significantly warmer than surrounding rural areas.

This early-season heat wave serves as a stark reminder of the urgent need to address climate change and its impact on our environment and public health. Efforts to reduce greenhouse gas emissions and implement sustainable practices are crucial in mitigating the effects of global warming and preventing future extreme weather events.