The temperature again today will soar to pleasantly warm levels, thanks to the absence of any major cloud cover. A combination of sunshine and a southwesterly flow will create an even warmer day on Saturday, with the high reaching 70°F (21°C). This type of setup is often seen during the spring months in Boston, where a high pressure center off the coast of the Carolinas sets up a flow from the southwest that draws much warmer air into our region. An approaching cold front will bring cloud cover on Sunday and not allow the temperature to become as warm.
Saturday at 1:32 p.m. is the vernal equinox, or more commonly known as the first day of spring (“vernal” is from the latin word for spring). On this day, every point on Earth experiences exactly 12 hours of sunlight. Astronomically, the vernal equinox is important because the sun’s position relative to background stars at that time helps define the “prime meridian” of the coordinate system used to plot locations of stars in the sky.