The first day of spring often brings a sense of renewal, but the weather can still be unpredictable. In many places, early spring mornings remain chilly due to lingering winter air masses. However, as the day progresses, temperatures can warm up significantly, creating a noticeable contrast between morning and afternoon conditions.
This phenomenon happens due to several factors, including seasonal transitions, sun angle, and atmospheric conditions. During winter, the Earth’s tilt causes lower solar angles, leading to colder temperatures. As the spring equinox arrives, the sun’s rays become more direct, allowing for greater warming during the day. However, remnants of winter air, particularly from high-pressure systems or cold fronts, can still bring frigid overnight temperatures.
On a typical first day of spring, the morning might start with temperatures near or below freezing, especially in areas that recently experienced winter conditions. This cold air is often trapped near the surface overnight due to radiational cooling, where heat escapes from the ground into the atmosphere. Once the sun rises, the increasing daylight and higher solar angle rapidly warm the air, leading to a much milder afternoon.
Weather patterns also play a role. A high-pressure system can create clear skies, allowing for maximum radiational cooling at night but also providing strong sunlight for daytime warming. Similarly, shifting jet streams and air masses influence temperature swings.
For many people, this contrast means bundling up in the morning and shedding layers by midday. The first day of spring often serves as a reminder that while winter’s grip may still be felt in the mornings, warmer and longer days are on the horizon. This mix of cold starts and spring-like afternoons is a hallmark of the season’s transition, signaling the gradual shift toward consistently warmer weather.
