Last summer, hundreds of millions of people were faced with triple-digit temperatures across the U.S. And now, weeks away from the hottest part of the year for the U.S., officials are warning it could happen again.
The forecast comes at what is expected to be the tail-end of the latest El Niño, a natural climate phenomenon that happens every few years when the Pacific Ocean develops above-normal sea surface temperatures, weakening trade winds. That typically brings dryer and warmer weather to the northern U.S. and more precipitation and flooding to the Southeast.
But now, the latest El Niño is "rapidly fading," the National Weather Service said in its outlook, with its counterpart, La Niña expected to take its place. Equally impactful, La Niña pushes warmer water towards Asia and causes more drought in the Southwest U.S. while bringing more precipitation and flooding in the Pacific Northwest.
"La Niña conditions [are] favored to strengthen and continue through boreal autumn and winter. Therefore, a La Niña Watch has also been issued."
The last La Niña event contributed to a record hurricane season when it started in 2020. An "explosive" season is expected this year as well, Weather Channel meteorologist Stephanie Abrams previously said.
Summer heat 2024 prediction
The National Oceanic and Atmospheric Administration recently released its seasonal temperature outlook with predictions for June, July and August. That outlook shows the majority of the U.S. likely seeing above-normal temperatures this summer. At least 20 states, including Washington, Texas, Colorado and almost the entire Northeast, are most likely to experience the out-of-norm heat. Only one small section of one state, southwest Alaska, is expected to have below-normal temperatures.
La Niña can also bring more heat domes, Dance said, which are essentially high-pressure areas that "keeps it sunny."
"It can last for days," he said. "…We're certainly looking out for that sort of thing this summer."
Summer rain 2024 prediction
There will be a wide range in precipitation for the summer of 2024. The western U.S. is expected to see below-normal rain, while the majority of the east coast and Alaska are expected to experience above-normal rainfall. The U.S. seasonal drought outlook shows that many areas where below-normal precipitation is expected are also likely to develop or have persisting drought conditions.
Officials brace for extreme heat in the U.S.
The U.S. Department of Health and Human Services is warning of the expected extreme temperatures in the upcoming months. On Monday, Philadelphia reached 90 degrees Fahrenheit – marking the first time the city has experienced such high heat in April in 15 years. Last year was recorded as the hottest one ever, with record temperatures seen in January, February, and March.
According to one model, temperatures are projected to be between 1 and 2 degrees Fahrenheit hotter than average "across almost all of the contiguous United States." Some regions, such as the Great Plains, the Midwest, southeastern New Mexico, and western Texas, could experience even more extreme heatwaves. Based on the model, the 90-day average temperature could be between 1.8 and 3.6 degrees Fahrenheit above normal for the summer season.
If the pattern of record-breaking heat persists, this summer could not only be extremely hot but also pose significant risks to public health.
Recent reports indicate that NOAA has expanded its heat risk tracking website, known as HeatRisk, in an effort to provide crucial information to vulnerable communities during periods of extreme heat. Certain groups, such as the elderly, children, and individuals with specific chronic health conditions, are particularly at risk of heat-related illnesses that can have fatal consequences. The forecast suggests that extreme heat events are expected to become more severe in the upcoming years.
NOAA Administrator Rick Spinrad highlighted the impact of climate change on the frequency and intensity of heat waves, leading to approximately 1,220 heat-related deaths in the U.S. annually. Spinrad emphasized that the previous year was the warmest on record globally, with the most recent winter also setting records for warmth. The introduction of HeatRisk aims to assist all individuals, especially those sensitive to heat, in preparing and safeguarding against the dangers associated with extreme heat.
