Summer Solstice Marks Longest Day of the Year in the U.S.

Alexis Thornton
By Alexis Thornton
June 21, 2026
Summer Solstice Marks Longest Day of the Year in the U.S.

The summer solstice is here, marking the official start of astronomical summer and the longest day of the year in the Northern Hemisphere. Here is what you need to know about the summer solstice, along with a look at the latest long-range forecast for the next three months across the U.S.

Understanding the Summer Solstice

The precise moment of the summer solstice varies from year to year within a range of a few days. This year's event falls on Sunday, June 21, across the U.S. and Europe. The moment marks the longest day and the shortest night of the year in the Northern Hemisphere and signifies the official start of astronomical summer.

Illustrated diagram showing Earth's axial orientation on the summer solstice (June 21), with daylight hours labeled at key latitudes: 24 hours at the Arctic Circle, 13.5 hours at the Tropic of Cancer, 12 hours at the Equator, 10.5 hours at the Tropic of Capricorn, and 0 hours at the Antarctic Circle. The North Pole experiences polar day — six months of continuous daylight — while the South Pole experiences polar night.
Summer Solstice 2025 | Credit: On the summer solstice, daylight ranges from 24 continuous hours at the Arctic Circle to zero at the Antarctic Circle. The continental U.S. receives roughly 14 to 16 hours of daylight depending on latitude. (Adobe Stock)

Conversely, the winter solstice occurs simultaneously for those in the Southern Hemisphere — marking the shortest day of the year and the longest night.

Despite being the longest day of the year, the solstice is not typically the hottest. Most of the U.S. records its warmest readings in late July or early August. Temperatures tend to rise incrementally after the summer solstice as accumulated heat continues to build — the oceans and land absorb solar energy for weeks after the solstice before temperatures peak.

The one region that typically sees its warmest temperatures in June is the extreme Desert Southwest, where the monsoon season that fires up around this time brings increased cloud cover and more frequent precipitation, cooling things down relative to the hottest weeks of May and early June.

What to Expect for Temperatures in the Months Ahead

Multiple long-range forecasting organizations are pointing to a broadly hot summer across the U.S. in 2026, with an El Niño developing and strengthening throughout the season as a key driver of the pattern.

NOAA Climate Prediction Center seasonal temperature outlook map issued May 21, 2026, valid for June through August 2026, showing above-normal temperatures favored across the vast majority of the contiguous United States. The strongest signal — 90 to 100% probability of above-normal temperatures — is concentrated across the Pacific Northwest, including Washington and Oregon. Above-normal heat is also favored across California, the Rockies, the Plains, the Gulf Coast, and the Southeast, with equal-chances areas limited to portions of the upper Midwest and northern Great Plains.
Credit: NOAA's summer 2026 temperature outlook shows above-normal heat favored across most of the country, with the strongest signal — 90 to 100% probability — centered on the Pacific Northwest. (NOAA/CPC)

The hottest conditions compared to historical averages are expected to focus on the West and Northwest — California, Oregon, Washington, Idaho, Montana, Nevada, and Utah are among the states forecast to see the most significant above-normal heat. That warmth extends east into the northern Rockies and portions of the Plains.

Unlike some prior summers, the South and Gulf Coast are not expected to see relief. The Gulf States are forecast to run hotter than average as well, with persistent heat and humidity through the heart of the summer months. Florida and the broader Southeast are also expected to trend above normal overall.

The Northeast and Great Lakes regions should expect a mix of warm-to-hot conditions, with periods of high humidity and scattered thunderstorms — and a potential late surge of heat and higher humidity later in the season.

What the Long-Range Forecast Says About Rain and Drought

The precipitation picture for summer 2026 is more regionally divided than the temperature outlook.

NOAA Climate Prediction Center seasonal precipitation outlook map issued May 21, 2026, valid for June through August 2026, showing above-normal precipitation favored across the Desert Southwest monsoon region — primarily Utah, Colorado, Arizona, and New Mexico — as well as portions of the Northeast. Below-normal precipitation is forecast for the Pacific Northwest coast, the upper Midwest, and a sliver of the Gulf Coast. Most of the contiguous U.S. falls within the equal-chances range for precipitation.
Credit: NOAA's summer 2026 precipitation outlook shows wetter-than-normal conditions favored for the Desert Southwest monsoon region, while the Pacific Northwest and parts of the upper Midwest face a drier-than-normal summer. (NOAA/CPC)

The Desert Southwest is forecast to see an active North American monsoon season, which will bring higher-than-normal rainfall to Arizona and New Mexico — along with a risk of flash flooding and lightning-sparked fires. The Plains, Mississippi Valley, and Ohio Valley are also expected to see above-average rainfall and a heightened flash flood risk, particularly in June and July.

However, conditions are expected to shift as the summer progresses. The Northwest and Northern California are forecast to see significantly below-normal precipitation, fueling expanding drought and an elevated wildfire threat. By late summer, dryness is expected to intensify across the Mid-South, Texas, and into the Midwest, with drought conditions potentially worsening through September.

Severe weather — including tornadoes and derechos — is forecast to be most active from the Plains through the Midwest and Ohio Valley in June and July before shifting eastward later in the season.


Weather changes fast, so help your community stay prepared. Share this story with friends, family, or your group chat, and keep your forecast in the now with Weather Forecast Now.

Latest News

Related Stories