{"abstract":"Humid weather feels hundreds of degrees hot.","category":"Weather index computation","checks":8,"contract":"Input air temperature degC, RH percent, wind in km/h measured at 10 m. e = RH/100*6.105*exp(17.27*Ta/(237.7+Ta)) hPa; wind in m/s = km/h / 3.6; AT = Ta + 0.33e - 0.70ws - 4.00 rounded to 0.1.","contract_signature":"ta, rh, wind_kmh","evaluation_group":"w2-weather_index_computation-apparent-temperature","failed_approach":"Using the humidity deficit (1 - RH/100) makes dry air feel hotter than humid air.","family":"w2-weather_index_computation-apparent-temperature-humidity-fraction","id":"FA-70936","implementations":{"attempt":{"sha256":"3249f60cf6637d4a050920d15e685772c01d103a1366375770aee6a8acfaa072","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(ta, rh, wind_kmh):\n    e = (1 - rh / 100.0) * 6.105 * math.exp(17.27 * ta / (237.7 + ta))\n    ws = wind_kmh / 3.6\n    at = ta + 0.33 * e - 0.70 * ws - 4.00\n    return round(at, 1)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['-5 C 10% RH wind 0 km/h', [-5, 10, 0], -8.9], ['-5 C 10% RH wind 10 km/h', [-5, 10, 10], -10.8], ['-5 C 10% RH wind 36 km/h', [-5, 10, 36], -15.9], ['-5 C 10% RH wind 72 km/h', [-5, 10, 72], -22.9], ['-5 C 50% RH wind 0 km/h', [-5, 50, 0], -8.3], ['-5 C 50% RH wind 10 km/h', [-5, 50, 10], -10.2], ['-5 C 50% RH wind 36 km/h', [-5, 50, 36], -15.3], ['-5 C 50% RH wind 72 km/h', [-5, 50, 72], -22.3]], [['-5 C 10% RH wind 72 km/h', [-5, 10, 72], -22.9], ['-5 C 50% RH wind 72 km/h', [-5, 50, 72], -22.3], ['-5 C 90% RH wind 0 km/h', [-5, 90, 0], -7.7], ['-5 C 90% RH wind 10 km/h', [-5, 90, 10], -9.7], ['-5 C 90% RH wind 36 km/h', [-5, 90, 36], -14.7], ['-5 C 90% RH wind 72 km/h', [-5, 90, 72], -21.7], ['0 C 10% RH wind 0 km/h', [0, 10, 0], -3.8], ['0 C 10% RH wind 10 km/h', [0, 10, 10], -5.7]], [['-5 C 50% RH wind 36 km/h', [-5, 50, 36], -15.3], ['0 C 10% RH wind 36 km/h', [0, 10, 36], -10.8], ['0 C 10% RH wind 72 km/h', [0, 10, 72], -17.8], ['0 C 50% RH wind 0 km/h', [0, 50, 0], -3.0], ['0 C 50% RH wind 10 km/h', [0, 50, 10], -4.9], ['0 C 50% RH wind 36 km/h', [0, 50, 36], -10.0], ['0 C 50% RH wind 72 km/h', [0, 50, 72], -17.0], ['0 C 90% RH wind 0 km/h', [0, 90, 0], -2.2]], [['-5 C 90% RH wind 10 km/h', [-5, 90, 10], -9.7], ['0 C 90% RH wind 10 km/h', [0, 90, 10], -4.1], ['0 C 90% RH wind 36 km/h', [0, 90, 36], -9.2], ['0 C 90% RH wind 72 km/h', [0, 90, 72], -16.2], ['12 C 10% RH wind 0 km/h', [12, 10, 0], 8.5], ['12 C 10% RH wind 10 km/h', [12, 10, 10], 6.5], ['12 C 10% RH wind 36 km/h', [12, 10, 36], 1.5], ['12 C 10% RH wind 72 km/h', [12, 10, 72], -5.5]], [['0 C 10% RH wind 0 km/h', [0, 10, 0], -3.8], ['12 C 50% RH wind 0 km/h', [12, 50, 0], 10.3], ['12 C 50% RH wind 10 km/h', [12, 50, 10], 8.4], ['12 C 50% RH wind 36 km/h', [12, 50, 36], 3.3], ['12 C 50% RH wind 72 km/h', [12, 50, 72], -3.7], ['12 C 90% RH wind 0 km/h', [12, 90, 0], 12.2], ['12 C 90% RH wind 10 km/h', [12, 90, 10], 10.2], ['12 C 90% RH wind 36 km/h', [12, 90, 36], 5.2]]]\nfor label, args, expected in fixtures[N - 1]:\n    check(label, solve(*args), expected)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"},"broken":{"sha256":"52de357872548caa2ea3cccb0e02aee240fcd70cdf6ca81e52462e20bca0144f","source":"\"\"\"Failure Map reference implementation. Python standard library only.\"\"\"\nimport json\nimport math\nN = 1\nobservations = []\ndef solve(ta, rh, wind_kmh):\n    e = rh * 6.105 * math.exp(17.27 * ta / (237.7 + ta))\n    ws = wind_kmh / 3.6\n    at = ta + 0.33 * e - 0.70 * ws - 4.00\n    return round(at, 1)\ndef check(label, actual, expected):\n    observations.append({\"check\": label, \"actual\": actual, \"expected\": expected, \"passed\": actual == expected})\nfixtures = [[['-5 C 10% RH wind 0 km/h', [-5, 10, 0], -8.9], ['-5 C 10% RH wind 10 km/h', [-5, 10, 10], -10.8], ['-5 C 10% RH wind 36 km/h', [-5, 10, 36], -15.9], ['-5 C 10% RH wind 72 km/h', [-5, 10, 72], -22.9], ['-5 C 50% RH wind 0 km/h', [-5, 50, 0], -8.3], ['-5 C 50% RH wind 10 km/h', [-5, 50, 10], -10.2], ['-5 C 50% RH wind 36 km/h', [-5, 50, 36], -15.3], ['-5 C 50% RH wind 72 km/h', [-5, 50, 72], -22.3]], [['-5 C 10% RH wind 72 km/h', [-5, 10, 72], -22.9], ['-5 C 50% RH wind 72 km/h', [-5, 50, 72], -22.3], ['-5 C 90% RH wind 0 km/h', [-5, 90, 0], -7.7], ['-5 C 90% RH wind 10 km/h', [-5, 90, 10], -9.7], ['-5 C 90% RH wind 36 km/h', [-5, 90, 36], -14.7], ['-5 C 90% RH wind 72 km/h', [-5, 90, 72], -21.7], ['0 C 10% RH wind 0 km/h', [0, 10, 0], -3.8], ['0 C 10% RH wind 10 km/h', [0, 10, 10], -5.7]], [['-5 C 50% RH wind 36 km/h', [-5, 50, 36], -15.3], ['0 C 10% RH wind 36 km/h', [0, 10, 36], -10.8], ['0 C 10% RH wind 72 km/h', [0, 10, 72], -17.8], ['0 C 50% RH wind 0 km/h', [0, 50, 0], -3.0], ['0 C 50% RH wind 10 km/h', [0, 50, 10], -4.9], ['0 C 50% RH wind 36 km/h', [0, 50, 36], -10.0], ['0 C 50% RH wind 72 km/h', [0, 50, 72], -17.0], ['0 C 90% RH wind 0 km/h', [0, 90, 0], -2.2]], [['-5 C 90% RH wind 10 km/h', [-5, 90, 10], -9.7], ['0 C 90% RH wind 10 km/h', [0, 90, 10], -4.1], ['0 C 90% RH wind 36 km/h', [0, 90, 36], -9.2], ['0 C 90% RH wind 72 km/h', [0, 90, 72], -16.2], ['12 C 10% RH wind 0 km/h', [12, 10, 0], 8.5], ['12 C 10% RH wind 10 km/h', [12, 10, 10], 6.5], ['12 C 10% RH wind 36 km/h', [12, 10, 36], 1.5], ['12 C 10% RH wind 72 km/h', [12, 10, 72], -5.5]], [['0 C 10% RH wind 0 km/h', [0, 10, 0], -3.8], ['12 C 50% RH wind 0 km/h', [12, 50, 0], 10.3], ['12 C 50% RH wind 10 km/h', [12, 50, 10], 8.4], ['12 C 50% RH wind 36 km/h', [12, 50, 36], 3.3], ['12 C 50% RH wind 72 km/h', [12, 50, 72], -3.7], ['12 C 90% RH wind 0 km/h', [12, 90, 0], 12.2], ['12 C 90% RH wind 10 km/h', [12, 90, 10], 10.2], ['12 C 90% RH wind 36 km/h', [12, 90, 36], 5.2]]]\nfor label, args, expected in fixtures[N - 1]:\n    check(label, solve(*args), expected)\nprint(json.dumps({\"observations\": observations, \"passed\": all(x[\"passed\"] for x in observations)}, ensure_ascii=False))\nraise SystemExit(0 if all(x[\"passed\"] for x in observations) else 1)\n"}},"limitations":"Stipulated deterministic teaching model of an operational weather index; coefficients and thresholds are fixed by the contract and no claim of standards conformance is made. This reproducer isolates one failure mechanism. Results cover the supplied fixtures. Variants within a family share a test contract and should remain grouped when constructing evaluation splits. Related mechanisms with a shared evaluation_group must also remain together; these controlled models are not independent production incidents.","method":"Deterministic executable model with adversarial boundary fixtures.","provenance":{"created_by":"Failure Map","dependencies":"Python standard library","family":"w2-weather_index_computation-apparent-temperature-humidity-fraction","generated_at":"2026-09-29T14:48:25.234900+00:00","license":"CC0-1.0","python":"3.12.14","seed":1,"split":"open-access"},"relevance":"Feels-like temperature on consumer forecasts uses this non-radiative apparent temperature.","root_cause":"Relative humidity in percent multiplies the saturation vapour pressure without conversion to a fraction.","sha256":"e544a6a6589a044100a7ae85e33bda64a8c5c5742e356a240f98996e4532b315","title":"Shade apparent temperature: humidity fraction · case 01","variant":1,"variant_policy":"Five numbered records share a model and may reuse boundary fixtures.","verified":true,"visibility":"public","verification":{"attempt":{"elapsed_ms":37.955,"exit_code":1,"observations":[{"actual":-7.7,"check":"-5 C 10% RH wind 0 km/h","expected":-8.9,"passed":false},{"actual":-9.7,"check":"-5 C 10% RH wind 10 km/h","expected":-10.8,"passed":false},{"actual":-14.7,"check":"-5 C 10% RH wind 36 km/h","expected":-15.9,"passed":false},{"actual":-21.7,"check":"-5 C 10% RH wind 72 km/h","expected":-22.9,"passed":false},{"actual":-8.3,"check":"-5 C 50% RH wind 0 km/h","expected":-8.3,"passed":true},{"actual":-10.2,"check":"-5 C 50% RH wind 10 km/h","expected":-10.2,"passed":true},{"actual":-15.3,"check":"-5 C 50% RH wind 36 km/h","expected":-15.3,"passed":true},{"actual":-22.3,"check":"-5 C 50% RH wind 72 km/h","expected":-22.3,"passed":true}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"-5 C 10% RH wind 0 km/h\", \"actual\": -7.7, \"expected\": -8.9, \"passed\": false}, {\"check\": \"-5 C 10% RH wind 10 km/h\", \"actual\": -9.7, \"expected\": -10.8, \"passed\": false}, {\"check\": \"-5 C 10% RH wind 36 km/h\", \"actual\": -14.7, \"expected\": -15.9, \"passed\": false}, {\"check\": \"-5 C 10% RH wind 72 km/h\", \"actual\": -21.7, \"expected\": -22.9, \"passed\": false}, {\"check\": \"-5 C 50% RH wind 0 km/h\", \"actual\": -8.3, \"expected\": -8.3, \"passed\": true}, {\"check\": \"-5 C 50% RH wind 10 km/h\", \"actual\": -10.2, \"expected\": -10.2, \"passed\": true}, {\"check\": \"-5 C 50% RH wind 36 km/h\", \"actual\": -15.3, \"expected\": -15.3, \"passed\": true}, {\"check\": \"-5 C 50% RH wind 72 km/h\", \"actual\": -22.3, \"expected\": -22.3, \"passed\": true}], \"passed\": false}\n"},"broken":{"elapsed_ms":38.149,"exit_code":1,"observations":[{"actual":4.9,"check":"-5 C 10% RH wind 0 km/h","expected":-8.9,"passed":false},{"actual":3.0,"check":"-5 C 10% RH wind 10 km/h","expected":-10.8,"passed":false},{"actual":-2.1,"check":"-5 C 10% RH wind 36 km/h","expected":-15.9,"passed":false},{"actual":-9.1,"check":"-5 C 10% RH wind 72 km/h","expected":-22.9,"passed":false},{"actual":60.5,"check":"-5 C 50% RH wind 0 km/h","expected":-8.3,"passed":false},{"actual":58.6,"check":"-5 C 50% RH wind 10 km/h","expected":-10.2,"passed":false},{"actual":53.5,"check":"-5 C 50% RH wind 36 km/h","expected":-15.3,"passed":false},{"actual":46.5,"check":"-5 C 50% RH wind 72 km/h","expected":-22.3,"passed":false}],"passed":false,"stderr":"","stdout":"{\"observations\": [{\"check\": \"-5 C 10% RH wind 0 km/h\", \"actual\": 4.9, \"expected\": -8.9, \"passed\": false}, {\"check\": \"-5 C 10% RH wind 10 km/h\", \"actual\": 3.0, \"expected\": -10.8, \"passed\": false}, {\"check\": \"-5 C 10% RH wind 36 km/h\", \"actual\": -2.1, \"expected\": -15.9, \"passed\": false}, {\"check\": \"-5 C 10% RH wind 72 km/h\", \"actual\": -9.1, \"expected\": -22.9, \"passed\": false}, {\"check\": \"-5 C 50% RH wind 0 km/h\", \"actual\": 60.5, \"expected\": -8.3, \"passed\": false}, {\"check\": \"-5 C 50% RH wind 10 km/h\", \"actual\": 58.6, \"expected\": -10.2, \"passed\": false}, {\"check\": \"-5 C 50% RH wind 36 km/h\", \"actual\": 53.5, \"expected\": -15.3, \"passed\": false}, {\"check\": \"-5 C 50% RH wind 72 km/h\", \"actual\": 46.5, \"expected\": -22.3, \"passed\": false}], \"passed\": false}\n"}},"member_only":{"stages":["fixed"],"fields":["implementations.fixed","verification.fixed","harness","repair"],"note":"The verified repair, its recorded checks, the repair description, and the scoring harness are available to members."}}