This region experiences warm (but not hot) and dry summers, with no average monthly temperatures above 71.6 °F. According to the Köppen Climate Classification system, Ilwaco has a warm-summer Mediterranean climate, abbreviated "Csb" on climate maps. As of the census of 2010, there were 936 people, 443 households, and 257 families living in the city. The population density was . There were 567 housing units at an average density of . The racial makeup of the city was 89.9% White, 0.3% African American, 2.1% Native American, 0.5% Asian, 3.6% from other races, and 3.5% from two or more races. Hispanic or Latino of any race were 5.7% of the population. There were 443 households of which 21.2% had children under the age of 18 living with them, 46.7% were married couples living together, 8.4% had a female householder with no husband present, 2.9% had a male householder with no wife present, and 42.0% were non-families. 35.7% of all households were made up of individuals and 13.7% had someone living alone who was 65 years of age or older. The average household size was 2.11 and the average family size was 2.68. The median age in the city was 50.2 years. 16.7% of residents were under the age of 18; 5.2% were between the ages of 18 and 24; 21.2% were from 25 to 44; 35.3% were from 45 to 64; and 21.6% were 65 years of age or older. The gender makeup of the city was 51.5% male and 48.5% female. As of the census of 2000, there were 950 people, 416 households, and 260 families living in the city. The population density was 461.5 people per square mile (178.1/km²). There were 524 housing units at an average density of 254.6 per square mile (98.2/km²). The racial makeup of the city was 92.84% White, 0.53% African American, 1.37% Native American, 0.42% Asian, 0.11% Pacific Islander, 1.79% from other races, and 2.95% from two or more races. Hispanic or Latino of any race were 5.26% of the population. 15.9% were of German, 13.6% Finnish, 10.1% English, 5.8% American, 5.2% Swedish and 5.1% Norwegian ancestry according to Census 2000.