Although Saturday's temperatures have left the Chicago area in a mid-winter chill, the official start to spring is just two days away, as the vernal equinox occurs Monday afternoon.
While meteorological seasons are generally defined as periods of three months beginning at the start of every third month, astronomical seasons are aligned with biannual equinoxes and solstices.
The vernal and autumnal equinoxes mark the beginning of spring and fall, while the winter and summer solstices define the astronomical start of those seasons respectively.
On the first day of spring, also the day of the vernal equinox, daytime and nighttime hours are roughly equal, just as they are during the autumnal equinox in late September, according to the Adler Planetarium.
This year's vernal equinox will occur on Monday, March 20 at 4:24 p.m., which will mark the astronomical beginning of spring.
From the vernal equinox up until the summer solstice, daylight hours will increase as dark-sky hours decrease. The date of the summer solstice marks the day of the calendar year with the highest amount of daylight hours.
While temperatures likely won't climb out of the 20s on Saturday, it will start to feel just a bit more like spring by the time of the vernal equinox.
Local
After a sunny Sunday with temperatures likely in the low 40s, skies will be mostly cloudy as highs reach near 50 degrees on Monday.
Feeling out of the loop? We'll catch you up on the Chicago news you need to know. Sign up for the weekly Chicago Catch-Up newsletter.