Vernal equinox, as viewed using GOES-13
GOES-13 0.63 µm visible channel image (with plot of surface air temperature)
The vernal equinox — commonly referred to as the “first day of Spring” in the Northern Hemisphere — occurred at 11:02 UTC on 20 March 2013. A GOES-13 full disk visible image at 11:45 UTC (above) showed the cloud features on the sun-lit portions of the Earth at that time, along with the large range of surface air temperatures: from -36 F or -38 C in northern Canada to 106 F or 41 C in western Africa (temperature contours). One of the more prominent features seen on the visible image was the large swirl of clouds associated with an occluded mid-latitude cyclone over the eastern North Atlantic Ocean (surface analysis).
