From CA CRFG website:
Winters (syn, M20222, Southland)
Origin Miami, USDA, 1959. Seedling of Ono, Philippine type, polyembryonic. Tree broad, production variable. Fruit medium, to 14 oz., smaller in desert, shape half-round, yellow blushed red. Subject to anthracnose, resists soft nose. Parthenocarpic fruit will reach full size. Season midseason (Nov-Dec), ripens well if picked immature. For coast, foothills, interior.
Edit: I originally thought Peggy...after Peggy Winter, but got confused.