{"metadata":{"title":"Chatham Muni, MA Monthly Climate Normals","page_url":"https://plainclimate.com/city/chatham-muni-ma","primary_station_id":"USW00094624","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, \"Chatham Muni, MA Climate Normals\". https://plainclimate.com/city/chatham-muni-ma","row_count":12},"annual_summary":{"city_slug":"chatham-muni-ma","ann_tavg":50.9,"ann_tmax":57.7,"ann_tmin":44.1,"ann_prcp":45.19,"ann_snow":null,"ann_htdd":5622,"ann_cldd":512.4,"frost_first":"11/04","frost_last":"04/13","growing_season":205,"warmest_month":7,"coldest_month":1,"wettest_month":12,"driest_month":7,"snowiest_month":null,"comfort_score":68},"data":[{"month":"January","month_number":1,"avg_temp_f":32.1,"avg_high_f":38.6,"avg_low_f":25.5,"precip_in":3.75,"snow_in":null,"heating_degree_days":1021.3,"cooling_degree_days":0,"days_with_precip":14.4,"days_with_snow":null,"days_freezing":22.9,"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":32.7,"avg_high_f":39.5,"avg_low_f":25.9,"precip_in":3.61,"snow_in":null,"heating_degree_days":904.4,"cooling_degree_days":0,"days_with_precip":12.6,"days_with_snow":null,"days_freezing":21.5,"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":37.6,"avg_high_f":43.9,"avg_low_f":31.2,"precip_in":4.43,"snow_in":null,"heating_degree_days":850.9,"cooling_degree_days":0,"days_with_precip":12.5,"days_with_snow":null,"days_freezing":17.1,"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":45.6,"avg_high_f":52.3,"avg_low_f":39,"precip_in":4.01,"snow_in":null,"heating_degree_days":580.7,"cooling_degree_days":0.2,"days_with_precip":13.7,"days_with_snow":null,"days_freezing":3.6,"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":55,"avg_high_f":61.9,"avg_low_f":48,"precip_in":3.34,"snow_in":null,"heating_degree_days":314.3,"cooling_degree_days":2.7,"days_with_precip":12.9,"days_with_snow":null,"days_freezing":0.1,"days_90f_plus":0,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"June","month_number":6,"avg_temp_f":64.3,"avg_high_f":71.5,"avg_low_f":57.2,"precip_in":2.95,"snow_in":null,"heating_degree_days":80.3,"cooling_degree_days":60.7,"days_with_precip":12.5,"days_with_snow":null,"days_freezing":0,"days_90f_plus":0.3,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"July","month_number":7,"avg_temp_f":71.4,"avg_high_f":78.7,"avg_low_f":64.2,"precip_in":2.79,"snow_in":null,"heating_degree_days":5.5,"cooling_degree_days":205.4,"days_with_precip":11.4,"days_with_snow":null,"days_freezing":0,"days_90f_plus":0.8,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"August","month_number":8,"avg_temp_f":70.6,"avg_high_f":77.7,"avg_low_f":63.5,"precip_in":3.03,"snow_in":null,"heating_degree_days":7.3,"cooling_degree_days":180.9,"days_with_precip":11.4,"days_with_snow":null,"days_freezing":0,"days_90f_plus":0.2,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"September","month_number":9,"avg_temp_f":64.3,"avg_high_f":71.1,"avg_low_f":57.5,"precip_in":3.58,"snow_in":null,"heating_degree_days":79.2,"cooling_degree_days":58.1,"days_with_precip":12.8,"days_with_snow":null,"days_freezing":0,"days_90f_plus":0,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null},{"month":"October","month_number":10,"avg_temp_f":54.3,"avg_high_f":61.3,"avg_low_f":47.4,"precip_in":4.23,"snow_in":null,"heating_degree_days":334.6,"cooling_degree_days":4.4,"days_with_precip":14.2,"days_with_snow":null,"days_freezing":0.8,"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":45.4,"avg_high_f":52.1,"avg_low_f":38.8,"precip_in":4.47,"snow_in":null,"heating_degree_days":586.5,"cooling_degree_days":0,"days_with_precip":12.5,"days_with_snow":null,"days_freezing":7.5,"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":37.3,"avg_high_f":43.9,"avg_low_f":30.8,"precip_in":5,"snow_in":null,"heating_degree_days":857.1,"cooling_degree_days":0,"days_with_precip":14.2,"days_with_snow":null,"days_freezing":18.6,"days_90f_plus":0,"humidity_pct":null,"wind_speed_mph":null,"clear_sky_pct":null,"overcast_pct":null}]}