• Meteorological spring starts on March 1 and is based on annual temperature cycles, while astronomical spring starts on March 20 and is based on the Earth’s position relative to the sun.
• The spring equinox, which occurs at the start of astronomical spring, is when the sun’s rays equally shine on both of the Earth’s hemispheres.

The “second” start to spring takes place this week on Thursday when astronomical spring begins.

According to meteorologists, spring began on March 1, but to others the first day of spring hasn’t quite yet arrived, said EarthSky said.

Meteorologists and climatologists use a slightly different time scale for meteorological seasons than for astronomical winter, spring, summer, and fall, NOAA says.

The difference is because the astronomical seasons are based on the position of the Earth in relation to the sun, whereas the meteorological seasons are based on the annual temperature cycle and help scientists track climate and weather trends.

Here’s what to know about meteorological and astronomical spring.

When does spring start 2025?

Astronomical spring starts at 5:01 a.m. Thursday, March 20.

What is the difference between meteorological spring and astronomical spring?

There are two starts to spring, and here’s why, according to NOAA:

• Meteorological spring: Meteorological seasons are broken down into groupings of three months in our civil calendar based on the annual temperature cycle. We generally think of winter as the coldest time of the year and summer as the warmest time of the year, with spring and fall being the transition seasons. In the southern hemisphere, the seasons are reversed where summer occurs when the South Pole is oriented towards the sun, and winter happens when the South Pole faces away.
• Astronomical spring: The Earth’s orbit forms the basis for the astronomical calendar in which seasons are defined by two solstices and two equinoxes. The Earth is tilted 23.5 degrees on its axis of rotation, and how the North Pole is oriented toward or away from the sun determines two of these astronomical dates. Exact timing for the astronomical spring and fall seasons are subject to change because the timing is dependent on the Earth’s rotation, NOAA said.

What is the spring equinox?

The equinox marks a seasonal transition, meaning the Earth will be in between the summer and winter solstices. During the spring equinox, the sun’s rays will equally shine the Earth’s two hemispheres.

The next astronomical season begins on June 21, 2025, marking the start of summer and the summer solstice.

More: It’s going to snow this week in the UP. Where they could see 16 inches in Michigan

What will the weather be like in Michigan 2025?

“Get ready for a “Thunder and Zing Spring!” Farmers’ Almanac long range weather forecast says spring weather will take its time arriving, allowing winter conditions to linger, especially across the Midwest, Great Lakes, New England, and Northeast regions,” the Farmers’ Almanac said.

The Almanac also predicts fair and “unsettled” weather for Easter on April 20, 2025.

The Old Farmer’s Almanac predicts above-normal temperatures and rainfall across Michigan, with drier conditions in the Upper Peninsula and wetter conditions in the Lower Peninsula.

What is the National Weather Service predicting for spring in Michigan 2025?

The National Weather Service issued prediction on Feb. 20, for March, April and May weather. Officials expect a 40% to 50% chance for above normal precipitation in the Lower Peninsula.

As for temperature, the weather service said Michigan has equal chances for spring temperatures, essentially it could be warmer or colder than usual.

Contact Sarah Moore @ [email protected]