{ "slug": "boise-id", "place": { "name": "Boise", "state": "ID", "census_name": "Boise City city", "census_geoid": "1608830", "lat": 43.59934, "lon": -116.22982, "station_distance_km": 3.7 }, "station": { "id": "USW00024131", "name": "BOISE AIR TERMINAL, ID US", "lat": 43.5667, "lon": -116.2406, "elevation_m": 857.7, "elevation_ft": 2814, "source_urls": { "monthly": "https://www.ncei.noaa.gov/data/normals-monthly/1991-2020/access/USW00024131.csv", "annual": "https://www.ncei.noaa.gov/data/normals-annualseasonal/1991-2020/access/USW00024131.csv" } }, "period": "1991-2020", "units": { "temperature": "F", "precipitation": "in", "snowfall": "in", "days": "days", "dates": "MM-DD", "prob_low_le_32f_pct": "percent" }, "months": [ { "month": 1, "name": "January", "high_f": 38.8, "low_f": 25.5, "mean_f": 32.2, "precip_in": 1.41, "snow_in": 5.3, "days_precip_ge_0_01in": 11.1, "days_precip_ge_0_10in": 5.1, "days_snow_ge_1_0in": 1.8, "days_high_ge_90f": 0.0, "days_high_le_32f": 6.4, "days_low_le_32f": 25.5, "prob_low_le_32f_pct": 100.0 }, { "month": 2, "name": "February", "high_f": 46.0, "low_f": 29.0, "mean_f": 37.5, "precip_in": 1.0, "snow_in": 3.3, "days_precip_ge_0_01in": 9.1, "days_precip_ge_0_10in": 3.8, "days_snow_ge_1_0in": 1.2, "days_high_ge_90f": 0.0, "days_high_le_32f": 1.3, "days_low_le_32f": 20.1, "prob_low_le_32f_pct": 100.0 }, { "month": 3, "name": "March", "high_f": 55.5, "low_f": 34.9, "mean_f": 45.2, "precip_in": 1.33, "snow_in": 1.2, "days_precip_ge_0_01in": 10.1, "days_precip_ge_0_10in": 4.8, "days_snow_ge_1_0in": 0.5, "days_high_ge_90f": 0.0, "days_high_le_32f": 0.1, "days_low_le_32f": 11.2, "prob_low_le_32f_pct": 99.9 }, { "month": 4, "name": "April", "high_f": 62.3, "low_f": 39.6, "mean_f": 50.9, "precip_in": 1.23, "snow_in": 0.1, "days_precip_ge_0_01in": 9.2, "days_precip_ge_0_10in": 4.1, "days_snow_ge_1_0in": 0.0, "days_high_ge_90f": 0.1, "days_high_le_32f": 0.0, "days_low_le_32f": 5.2, "prob_low_le_32f_pct": 90.5 }, { "month": 5, "name": "May", "high_f": 72.3, "low_f": 47.5, "mean_f": 59.9, "precip_in": 1.45, "snow_in": 0.0, "days_precip_ge_0_01in": 8.4, "days_precip_ge_0_10in": 3.9, "days_snow_ge_1_0in": 0.0, "days_high_ge_90f": 1.4, "days_high_le_32f": 0.0, "days_low_le_32f": 0.8, "prob_low_le_32f_pct": 28.5 }, { "month": 6, "name": "June", "high_f": 81.4, "low_f": 54.1, "mean_f": 67.8, "precip_in": 0.75, "snow_in": 0.0, "days_precip_ge_0_01in": 5.3, "days_precip_ge_0_10in": 2.4, "days_snow_ge_1_0in": 0.0, "days_high_ge_90f": 6.6, "days_high_le_32f": 0.0, "days_low_le_32f": 0.0, "prob_low_le_32f_pct": 0.3 }, { "month": 7, "name": "July", "high_f": 92.7, "low_f": 61.9, "mean_f": 77.3, "precip_in": 0.21, "snow_in": 0.0, "days_precip_ge_0_01in": 2.3, "days_precip_ge_0_10in": 0.6, "days_snow_ge_1_0in": 0.0, "days_high_ge_90f": 22.1, "days_high_le_32f": 0.0, "days_low_le_32f": 0.0, "prob_low_le_32f_pct": 0.0 }, { "month": 8, "name": "August", "high_f": 90.7, "low_f": 60.8, "mean_f": 75.8, "precip_in": 0.17, "snow_in": 0.0, "days_precip_ge_0_01in": 2.1, "days_precip_ge_0_10in": 0.4, "days_snow_ge_1_0in": 0.0, "days_high_ge_90f": 19.5, "days_high_le_32f": 0.0, "days_low_le_32f": 0.0, "prob_low_le_32f_pct": 0.0 }, { "month": 9, "name": "September", "high_f": 80.0, "low_f": 52.6, "mean_f": 66.3, "precip_in": 0.43, "snow_in": 0.0, "days_precip_ge_0_01in": 3.9, "days_precip_ge_0_10in": 1.4, "days_snow_ge_1_0in": 0.0, "days_high_ge_90f": 4.8, "days_high_le_32f": 0.0, "days_low_le_32f": 0.2, "prob_low_le_32f_pct": 2.9 }, { "month": 10, "name": "October", "high_f": 64.8, "low_f": 41.5, "mean_f": 53.2, "precip_in": 0.81, "snow_in": 0.1, "days_precip_ge_0_01in": 6.0, "days_precip_ge_0_10in": 2.4, "days_snow_ge_1_0in": 0.1, "days_high_ge_90f": 0.3, "days_high_le_32f": 0.0, "days_low_le_32f": 3.7, "prob_low_le_32f_pct": 80.2 }, { "month": 11, "name": "November", "high_f": 48.8, "low_f": 31.7, "mean_f": 40.3, "precip_in": 1.18, "snow_in": 2.0, "days_precip_ge_0_01in": 9.7, "days_precip_ge_0_10in": 4.1, "days_snow_ge_1_0in": 0.8, "days_high_ge_90f": 0.0, "days_high_le_32f": 1.6, "days_low_le_32f": 16.3, "prob_low_le_32f_pct": 100.0 }, { "month": 12, "name": "December", "high_f": 38.8, "low_f": 25.4, "mean_f": 32.1, "precip_in": 1.54, "snow_in": 5.6, "days_precip_ge_0_01in": 12.0, "days_precip_ge_0_10in": 4.8, "days_snow_ge_1_0in": 1.7, "days_high_ge_90f": 0.0, "days_high_le_32f": 6.8, "days_low_le_32f": 25.2, "prob_low_le_32f_pct": 100.0 } ], "annual": { "high_f": 64.3, "low_f": 42.0, "mean_f": 53.2, "precip_in": 11.51, "snow_in": 17.6, "days_precip_ge_0_01in": 89.2, "days_snow_ge_1_0in": 6.1, "days_high_ge_90f": 54.9, "days_high_le_32f": 16.3, "days_low_le_32f": 108.2 }, "frost": { "semantics": { "last_spring": "PRBLST: an N% chance that the last night at or below the threshold comes on or after this date", "first_fall": "PRBFST: an N% chance that the first night at or below the threshold has come by this date", "season_days": "PRBGSL: length of the season above the threshold, days; P50 is the median" }, "thresholds_f": [ 36, 32, 28, 24, 20, 16 ], "probabilities_pct": [ 10, 20, 30, 40, 50, 60, 70, 80, 90 ], "table": { "36": { "status": "computed", "freeze_in_most_years": true, "last_spring": { "10": "05-29", "20": "05-19", "30": "05-14", "40": "05-10", "50": "05-08", "60": "05-04", "70": "05-01", "80": "04-28", "90": "04-23" }, "first_fall": { "10": "09-25", "20": "09-30", "30": "10-03", "40": "10-06", "50": "10-08", "60": "10-11", "70": "10-14", "80": "10-19", "90": "10-25" }, "season_days": { "10": 173.0, "20": 166.0, "30": 161.0, "40": 157.0, "50": 153.0, "60": 148.0, "70": 142.0, "80": 136.0, "90": 128.0 } }, "32": { "status": "computed", "freeze_in_most_years": true, "last_spring": { "10": "05-09", "20": "05-04", "30": "04-30", "40": "04-27", "50": "04-24", "60": "04-21", "70": "04-17", "80": "04-12", "90": "04-04" }, "first_fall": { "10": "10-05", "20": "10-10", "30": "10-14", "40": "10-18", "50": "10-21", "60": "10-24", "70": "10-27", "80": "10-31", "90": "11-05" }, "season_days": { "10": 203.0, "20": 196.0, "30": 190.0, "40": 185.0, "50": 179.0, "60": 175.0, "70": 171.0, "80": 164.0, "90": 156.0 } }, "28": { "status": "computed", "freeze_in_most_years": true, "last_spring": { "10": "04-25", "20": "04-18", "30": "04-12", "40": "04-06", "50": "04-02", "60": "03-30", "70": "03-24", "80": "03-18", "90": "03-10" }, "first_fall": { "10": "10-17", "20": "10-21", "30": "10-25", "40": "10-29", "50": "10-31", "60": "11-04", "70": "11-08", "80": "11-13", "90": "11-19" }, "season_days": { "10": 241.0, "20": 232.0, "30": 223.0, "40": 217.0, "50": 212.0, "60": 205.0, "70": 200.0, "80": 194.0, "90": 186.0 } }, "24": { "status": "computed", "freeze_in_most_years": true, "last_spring": { "10": "04-04", "20": "03-27", "30": "03-19", "40": "03-13", "50": "03-09", "60": "03-04", "70": "03-01", "80": "02-24", "90": "02-16" }, "first_fall": { "10": "10-24", "20": "10-30", "30": "11-04", "40": "11-09", "50": "11-13", "60": "11-17", "70": "11-21", "80": "11-25", "90": "12-01" }, "season_days": { "10": 276.0, "20": 266.0, "30": 260.0, "40": 252.0, "50": 246.0, "60": 241.0, "70": 234.0, "80": 226.0, "90": 215.0 } }, "20": { "status": "computed", "freeze_in_most_years": true, "last_spring": { "10": "03-09", "20": "03-02", "30": "02-27", "40": "02-23", "50": "02-19", "60": "02-14", "70": "02-09", "80": "02-02", "90": "01-20" }, "first_fall": { "10": "11-05", "20": "11-12", "30": "11-17", "40": "11-21", "50": "11-25", "60": "11-29", "70": "12-03", "80": "12-08", "90": "12-15" }, "season_days": { "10": 313.0, "20": 302.0, "30": 293.0, "40": 285.0, "50": 280.0, "60": 274.0, "70": 267.0, "80": 260.0, "90": 250.0 } }, "16": { "status": "computed", "freeze_in_most_years": true, "last_spring": { "10": "02-25", "20": "02-18", "30": "02-13", "40": "02-07", "50": "02-02", "60": "01-25", "70": "01-15", "80": "01-05", "90": "12-25" }, "first_fall": { "10": "11-14", "20": "11-23", "30": "11-27", "40": "12-02", "50": "12-07", "60": "12-11", "70": "12-16", "80": "12-24", "90": "01-04" }, "season_days": { "10": 346.0, "20": 334.0, "30": 326.0, "40": 318.0, "50": 311.0, "60": 305.0, "70": 298.0, "80": 289.0, "90": 277.0 } } }, "notes": [] }, "derived": { "hottest_month": { "month": 7, "name": "July", "value": 77.3 }, "coldest_month": { "month": 12, "name": "December", "value": 32.1 }, "hottest_month_by_high": { "month": 7, "name": "July", "value": 92.7 }, "wettest_month": { "month": 12, "name": "December", "value": 1.54 }, "driest_month": { "month": 8, "name": "August", "value": 0.17 }, "snowiest_month": { "month": 12, "name": "December", "value": 5.6 }, "winter": "cool", "summer": "hot", "precipitation": "semi-arid", "snow": "moderate", "annual_precip_in": 11.51, "annual_snow_in": 17.6, "annual_range_f": 45.2, "mean_daily_range_f": 22.3, "months_high_ge_90f": [ 7, 8 ], "months_low_le_32f": [ 1, 2, 11, 12 ], "last_spring_32f_p50": "04-24", "first_fall_32f_p50": "10-21", "freeze_free_days_p50": 179.0, "freeze_free_span_days_p50": 180 }, "rules": { "hottest_coldest_month": "by monthly mean temperature (MLY-TAVG-NORMAL); ties go to the earlier month", "wettest_driest_month": "by monthly precipitation normal (MLY-PRCP-NORMAL); ties go to the earlier month", "winter": { "basis": "mean temperature of the coldest month, F", "bands": [ [ null, 20, "very cold" ], [ 20, 32, "cold" ], [ 32, 45, "cool" ], [ 45, 60, "mild" ], [ 60, null, "warm" ] ] }, "summer": { "basis": "mean daily high of the hottest month (by high), F", "bands": [ [ null, 70, "cool" ], [ 70, 80, "mild" ], [ 80, 90, "warm" ], [ 90, 100, "hot" ], [ 100, null, "very hot" ] ] }, "precipitation": { "basis": "annual precipitation normal, inches (sum of months if no annual value)", "bands": [ [ null, 10, "arid" ], [ 10, 20, "semi-arid" ], [ 20, 40, "moderate" ], [ 40, 60, "wet" ], [ 60, null, "very wet" ] ] }, "snow": { "basis": "annual snowfall normal, inches; 'no data' when NOAA publishes no snowfall normal", "bands": [ [ null, 1, "rare or none" ], [ 1, 12, "light" ], [ 12, 36, "moderate" ], [ 36, 72, "heavy" ], [ 72, null, "very heavy" ] ] }, "bands": "lower bound inclusive, upper bound exclusive", "frost_free": "true when the 32F last-spring and first-fall P50 dates are -9999 with flag Y (insufficient values) and the 32F growing season P50 is 365 days or the annual number of nights at or below 32F rounds to 0.0", "freeze_free_days_p50": "NOAA ANN-TMIN-PRBGSL-T32FP50 (median length of the 32F freeze-free season), as published", "freeze_rare": "true when 32F dates are published but the 32F growing season P50 is 365 days: no 32F night in at least half of years; the P50 spring and fall dates then cross and freeze_free_span_days_p50 is null", "freeze_free_span_days_p50": "days from the 32F P50 last-spring date to the 32F P50 first-fall date (next year if the fall date is earlier in the calendar); differs from the NOAA median season length because a median of lengths is not the span between median dates" }, "flags": { "frost_free": false, "freeze_rare": false, "frost_data_missing": false, "year_round_frost_risk": false, "snow_normal_absent": false, "incomplete_months": [] }, "quality": { "high_f": { "column": "MLY-TMAX-NORMAL", "absent": false, "comp_flags": [ "S" ], "meas_flags": [], "years_min": 29, "missing_months": 0 }, "low_f": { "column": "MLY-TMIN-NORMAL", "absent": false, "comp_flags": [ "S" ], "meas_flags": [], "years_min": 26, "missing_months": 0 }, "mean_f": { "column": "MLY-TAVG-NORMAL", "absent": false, "comp_flags": [ "S" ], "meas_flags": [], "years_min": 26, "missing_months": 0 }, "precip_in": { "column": "MLY-PRCP-NORMAL", "absent": false, "comp_flags": [ "S" ], "meas_flags": [], "years_min": 30, "missing_months": 0 }, "snow_in": { "column": "MLY-SNOW-NORMAL", "absent": false, "comp_flags": [ "S" ], "meas_flags": [], "years_min": 29, "missing_months": 0 }, "days_precip_ge_0_01in": { "column": "MLY-PRCP-AVGNDS-GE001HI", "absent": false, "comp_flags": [ "S" ], "meas_flags": [], "years_min": 30, "missing_months": 0 }, "days_precip_ge_0_10in": { "column": "MLY-PRCP-AVGNDS-GE010HI", "absent": false, "comp_flags": [ "S" ], "meas_flags": [], "years_min": 30, "missing_months": 0 }, "days_snow_ge_1_0in": { "column": "MLY-SNOW-AVGNDS-GE010TI", "absent": false, "comp_flags": [ "S" ], "meas_flags": [ "X" ], "years_min": 30, "missing_months": 0 }, "days_high_ge_90f": { "column": "MLY-TMAX-AVGNDS-GRTH090", "absent": false, "comp_flags": [ "S" ], "meas_flags": [], "years_min": 29, "missing_months": 0 }, "days_high_le_32f": { "column": "MLY-TMAX-AVGNDS-LSTH032", "absent": false, "comp_flags": [ "S" ], "meas_flags": [], "years_min": 29, "missing_months": 0 }, "days_low_le_32f": { "column": "MLY-TMIN-AVGNDS-LSTH032", "absent": false, "comp_flags": [ "S" ], "meas_flags": [ "X" ], "years_min": 26, "missing_months": 0 }, "prob_low_le_32f_pct": { "column": "MLY-TMIN-PRBOCC-LSTH032", "absent": false, "comp_flags": [ "S" ], "meas_flags": [], "years_min": 26, "missing_months": 0 } }, "citation": { "monthly": "Palecki, Michael; Durre, Imke; Applequist, Scott; Arguez, Anthony; Lawrimore, Jay (2021). U.S. Climate Normals 2020: U.S. Monthly Climate Normals (1991-2020). Station USW00024131 (BOISE AIR TERMINAL, ID US). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/wck8-er13. Accessed 2026-10-09.", "annual": "Palecki, Michael; Durre, Imke; Applequist, Scott; Arguez, Anthony; Lawrimore, Jay (2021). U.S. Climate Normals 2020: U.S. Annual/Seasonal Climate Normals (1991-2020). Station USW00024131 (BOISE AIR TERMINAL, ID US). NOAA National Centers for Environmental Information. Dataset. https://doi.org/10.25921/4ek7-fk11. Accessed 2026-10-09.", "metadata_records": [ "https://www.ncei.noaa.gov/access/metadata/landing-page/bin/iso?id=gov.noaa.ncdc:C01620", "https://www.ncei.noaa.gov/access/metadata/landing-page/bin/iso?id=gov.noaa.ncdc:C01619" ] }, "retrieved": { "monthly": "2026-10-09", "annual": "2026-10-09" } }