Erm actually August/September. As based on events in the bible itself, it would have been couple months after Yom Kippur.
The Hebrew lunar calendar varies, but in 3BC the first of Elul, would have been September 11th by our count. So Based on events in the bible, but not exactly sure of exactly which year of the era, his birth could have been anywhere between late august to early september.
September 11th! CONSPIRACY!