Thoroughfares now in the southwest area of the city which extend east and west shall be named consecutively commencing with the first avenue (Highway 99E) south of the Southern Pacific Company right-of-way as follows:
S.W. 1st Avenue;
S.W. 2nd Avenue;
S.W. 3rd Avenue;
S.W. 4th Avenue;
S.W. 5th Avenue;
S.W. 6th Avenue;
S.W. 7th Avenue; and
S.W. 13th Avenue (S.W. Mundorff Road).