Spring equinox timing
Spring officially begins Friday, March 20 — the vernal equinox hits at 9:46 a.m. CDT, meaning equal daylight and darkness across the Northern Hemisphere (foxweather.com). Forecasters are also flagging March 20 for especially vivid auroras worldwide, a rare extra reason to plan late‑March night‑sky watching (foxweather.com).
The Sun crosses the celestial equator at 14:46 UTC on March 20, 2026 — that exact universal time is used by astronomers to mark the March equinox. (earthsky.org) That UTC instant corresponds to 10:46 a.m. EDT and 7:46 a.m. PDT in North American time zones, useful for cross‑country scheduling of events and broadcasts. (timeanddate.com) At the moment of the equinox the subsolar point (where the Sun is directly overhead) will lie in the Atlantic Ocean off the northeast coast of Brazil, not above any continental capital. (theweathernetwork.com) NOAA’s Space Weather Prediction Center has issued a G2 (moderate) geomagnetic storm watch covering March 19–21 tied to multiple CME arrivals and high‑speed stream effects. (swpc.noaa.gov) One of the Earth‑directed CMEs came from active region AR4392 after an M‑class flare on March 16, and forecasters expected its arrival to drive elevated geomagnetic activity around March 19–20. (geomag.bgs.ac.uk) Operational outlooks project 3‑hour Kp values near 6 (G2) during the March 19 window with G1 levels possible into March 20, opening the chance of auroras appearing as far south as mid‑United States latitudes. (pogodnik.com) Scientists point to the Russell–McPherron/equinoctial effect — a seasonal geometric alignment that tends to make Earth’s magnetosphere more receptive to solar wind around equinoxes — as a reason March increases aurora odds. (earthsky.org)
