(a) The northern boundary of the Southern Winter Seasonal Zone is the rhumb line from the east coast of the American continent at Cape Tres Puntas to the point latitude 34[deg] S., longitude 50[deg] W.; thence the parallel of latitude 34[deg] S. to longitude 17[deg] E.; thence the rhumb line to the point latitude 35[deg]10[min] S., longitude 20[deg] E.; thence the rhumb line to the point latitude 34[deg] S. longitude 28[deg] E.; thence along the rhumb line to the point latitude 35[deg]30[min] S., longitude 118[deg] E.; thence the rhumb line to Cape Grim on the northwest coast of Tasmania; thence along the north and east coasts of Tasmania to the southernmost point of Bruny Island; thence the rhumb line to Black Rock Point on Stewart Island; thence the rhumb line to the point latitude 47[deg] S., longitude 170[deg] E.; thence along the rhumb line to the point latitude 33[deg] S., longitude 170[deg] W.; and thence the parallel of latitude 33[deg] S. to the west coast of the American continent.
(1) Valparaiso is to be considered as being on the boundary line of the Summer and the Winter Seasonal Zones.
(2) Seasonal periods: Winter: April 16 to October 15.Summer: October 16 to April 15. [CGFR 68-60, 33 FR 10068, July 12, 1968]