Kostajnica, in Srpska, Bosnia and Herzegovina, is home to roughly 4,700 people in the Europe/Sarajevo time zone at 45.2°N latitude.
Recent weather here gives a sense of typical conditions: in 2025, Kostajnica recorded a mean annual temperature of 54°F, ranging from 18°F lows in January to 96°F highs in June, with about 33 inches of precipitation across the year.
View historical weather for Kostajnica · More cities in Srpska