{"metadata":{"title":"Crystal Lake, IL Monthly Climate Normals","page_url":"https://plainclimate.com/city/crystal-lake-il","primary_station_id":"USC00112048","source":"NOAA 1991-2020 U.S. Climate Normals","source_url":"https://www.ncei.noaa.gov/products/land-based-station/us-climate-normals","vintage":"2026-08-04","license":"CC0 1.0","license_url":"https://creativecommons.org/publicdomain/zero/1.0/","citation":"PlainClimate, \"Crystal Lake, IL Climate Normals\". https://plainclimate.com/city/crystal-lake-il","row_count":12},"annual_summary":{"city_slug":"crystal-lake-il","ann_tavg":49.1,"ann_tmax":59.1,"ann_tmin":39.1,"ann_prcp":39.35,"ann_snow":35.1,"ann_htdd":6520.2,"ann_cldd":771.1,"frost_first":"10/22","frost_last":"04/25","growing_season":180,"warmest_month":7,"coldest_month":1,"wettest_month":6,"driest_month":2,"snowiest_month":1,"comfort_score":59},"data":[{"month":"January","month_number":1,"avg_temp_f":22.9,"avg_high_f":31.5,"avg_low_f":14.2,"precip_in":1.97,"snow_in":10,"heating_degree_days":1306.4,"cooling_degree_days":0,"days_with_precip":8.6,"days_with_snow":6.2,"days_freezing":28.9,"days_90f_plus":0,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"February","month_number":2,"avg_temp_f":25.8,"avg_high_f":35.2,"avg_low_f":16.3,"precip_in":1.84,"snow_in":9,"heating_degree_days":1098.9,"cooling_degree_days":0,"days_with_precip":7.6,"days_with_snow":5.1,"days_freezing":27.2,"days_90f_plus":0,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"March","month_number":3,"avg_temp_f":36.6,"avg_high_f":46.8,"avg_low_f":26.4,"precip_in":2.51,"snow_in":4.4,"heating_degree_days":882.7,"cooling_degree_days":2.3,"days_with_precip":8.3,"days_with_snow":3,"days_freezing":22.1,"days_90f_plus":0,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"April","month_number":4,"avg_temp_f":48,"avg_high_f":59.2,"avg_low_f":36.7,"precip_in":3.76,"snow_in":1.2,"heating_degree_days":513.4,"cooling_degree_days":1.9,"days_with_precip":11,"days_with_snow":0.8,"days_freezing":9.1,"days_90f_plus":0,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"May","month_number":5,"avg_temp_f":59.6,"avg_high_f":71.3,"avg_low_f":47.9,"precip_in":4.98,"snow_in":0,"heating_degree_days":218.5,"cooling_degree_days":51,"days_with_precip":11.8,"days_with_snow":0.1,"days_freezing":0.3,"days_90f_plus":2.1,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"June","month_number":6,"avg_temp_f":69.4,"avg_high_f":80.3,"avg_low_f":58.4,"precip_in":5.26,"snow_in":0,"heating_degree_days":31.2,"cooling_degree_days":161.6,"days_with_precip":9.9,"days_with_snow":0,"days_freezing":0,"days_90f_plus":5.5,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"July","month_number":7,"avg_temp_f":73.3,"avg_high_f":84,"avg_low_f":62.5,"precip_in":3.9,"snow_in":0,"heating_degree_days":5.3,"cooling_degree_days":260.9,"days_with_precip":8.5,"days_with_snow":0,"days_freezing":0,"days_90f_plus":7.7,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"August","month_number":8,"avg_temp_f":71.6,"avg_high_f":82,"avg_low_f":61.2,"precip_in":3.81,"snow_in":0,"heating_degree_days":10.9,"cooling_degree_days":215.3,"days_with_precip":8.9,"days_with_snow":0,"days_freezing":0,"days_90f_plus":4,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"September","month_number":9,"avg_temp_f":63.4,"avg_high_f":74.4,"avg_low_f":52.4,"precip_in":3.54,"snow_in":0,"heating_degree_days":120.6,"cooling_degree_days":72.6,"days_with_precip":8,"days_with_snow":0,"days_freezing":0,"days_90f_plus":2.5,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"October","month_number":10,"avg_temp_f":52.2,"avg_high_f":61.9,"avg_low_f":42.4,"precip_in":3.2,"snow_in":0.2,"heating_degree_days":403.8,"cooling_degree_days":5.3,"days_with_precip":9.4,"days_with_snow":0.1,"days_freezing":3.4,"days_90f_plus":0,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"November","month_number":11,"avg_temp_f":39,"avg_high_f":47.5,"avg_low_f":30.5,"precip_in":2.48,"snow_in":1.6,"heating_degree_days":780.3,"cooling_degree_days":0.3,"days_with_precip":8.5,"days_with_snow":1.4,"days_freezing":18,"days_90f_plus":0,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"December","month_number":12,"avg_temp_f":28,"avg_high_f":35.5,"avg_low_f":20.4,"precip_in":2.1,"snow_in":8.7,"heating_degree_days":1148.4,"cooling_degree_days":0,"days_with_precip":9.2,"days_with_snow":5.4,"days_freezing":26.5,"days_90f_plus":0,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null}]}