Summer has just begun in the United States, but for millions of people, it already feels like late August. In just a few days, temperatures have climbed above 100°F (38°C) in several cities across the East Coast and the Midwest, with weather agencies now warning of “extreme risk” conditions for at least 15 million residents from Washington, D.C. to Florida.
In the nation’s capital, the thermometer hit 98°F (36.6°C), with humidity pushing the heat index past 104°F (40°C). In New York, highs of 95°F (35°C) are expected on Monday and Tuesday, with tropical nights that may not dip below 79°F (26°C). According to officials, these are the hottest days of the year so far — and the worst may still be ahead.
The impact is already visible. In Chicago, emergency services reported a surge in heat-related illness calls last Saturday. In Denver, where 100°F (38°C) set a June record, hospitals are urging residents to avoid outdoor activity during the hottest hours of the day.
Health authorities are issuing practical guidelines, especially for older adults: drink water frequently, even if not feeling thirsty; avoid direct sunlight; and stay in air-conditioned spaces during peak heat hours. Many cities have opened “cooling centers” — public spaces like libraries and community centers where people can find relief from the heat.
According to a federal study published in 2023, heat remains the deadliest form of weather in the United States, contributing to an average of over 800 deaths per year. And as the thermometer continues to rise, the most dangerous effects may come at night: due to climate change, nighttime temperatures are increasing faster than daytime highs, making it harder for the human body to recover.
The peak of this first heat wave is expected between Monday and Wednesday of next week, when more than 150 daily records — both for high temperatures and for warmest lows — could be broken. In cities like Boston, St. Louis, New York, and Chicago, some of the climate records date back over a century.
Meanwhile, the summer solstice will occur on Friday, June 21 at 10:42 p.m. ET — the longest day of the year. But in the U.S., it feels like summer has arrived early — and it’s only just begun.
