x1 is Summer(time)/(a)estival [hot season] in the southern hemisphere and Winter(time)/hibernal/hiemal [cold season] in the northern hemisphere of year x2 and for celestial body x3.
f1 = r1 = x1 (event; perhaps: spacetime coordinates) is a solstice of extreme r3 = x2 ("ka" construct or season; default: "ka zmadu", which means "Summer solstice", unless context makes this interpretation untenable) at location/of or for celestial body/object d3 = x3 with respect to orbit/sun x4.
x1 is Summer(time)/(a)estival [hot season] in the northern hemisphere and Winter(time)/hibernal/hiemal [cold season] in the southern hemisphere of year x2 and for celestial body x3.
x1 is Spring time/vernal [warming season] in the southern hemisphere and Autumn/autumnal [cooling season] in the northern hemisphere of year x2 and for celestial body x3.
x1 is Spring time/vernal [warming season] in the northern hemisphere and Autumn/autumnal [cooling season] in the southern hemisphere of year x2 and for celestial body x3.