Hello summer: The longest day of the year and solstice are here

The first day of the summer, the longest day of the year and the summer solstice officially arrived on Tuesday, June 21.

The big picture: Yet, the hot weather arrived in the U.S. and Europe before the summer solstice with extraordinary heat waves sending temperatures soaring into uncharted territory, Axios’ Andrew Freedman reports.

• The summer solstice, officially at 5:13 a.m. ET, marks the start of summer in the Northern Hemisphere when the Earth is at the point in its orbit where the North Pole is at its maximum tilt toward the sun, according to Almanac.com.
• It’s the longest day and shortest night of the calendar year in the Northern Hemisphere.
• The June solstice marks the start of winter in the Southern Hemisphere and is the shortest day of the year there.

Heat wave shattering records ahead of summer

Meanwhile, the early season extreme heat is a development meteorologists are calling "unsettling" and "unprecedented," Axios' Freedman reports.

• These events are a clear warning sign of global warming's growing influence on day-to-day weather.

Summers are becoming deadlier as climate change blankets millions in heat waves whose public health consequences were until recently not fully understood.

Why it matters: Extreme heat is increasingly taking a toll on children, pregnant people and other vulnerable populations, forcing authorities to roll out new strategies against an environmental threat that dwarfs floods, earthquakes and other natural disasters, Axios’ Arielle Dreher reports.

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