FA-71141 / Weather index computation / Open access

Haines lower-atmosphere severity index: stability lapse direction · case 01

Strong lapse rates score as stable while inversions score as unstable.

Verified by executionVariant 1 · 8 checks per implementationDownload source bundle ↓JSON ↗

ROOT CAUSE

The stability term subtracts the lower level from the upper one.

VERIFIED REPAIR

Use T(lower level) - T(upper level).

Unsuccessful approach: Taking the absolute value scores inversions as if they were steep lapse rates.

Case contract

temps/dews map pressure level (hPa) to degC. low: stability T950-T850 (<=3:1, <=7:2, else 3), moisture T850-Td850 (<=5:1, <=9:2, else 3); mid: T850-T700 (<=5, <=10), T850-Td850 (<=5, <=12); high: T700-T500 (<=17, <=21), T700-Td700 (<=14, <=20). Unknown elevation returns None. Return [sum, label] with 2-3 very low, 4 low, 5 moderate, 6 high.

Why this case matters

Fire behaviour analysts use the Haines index for plume-dominated fire potential.

1 / The failure

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(elev, temps, dews):
    levels = {"low": (950, 850, 850, 850, (3, 7), (5, 9)),
              "mid": (850, 700, 850, 850, (5, 10), (5, 12)),
              "high": (700, 500, 700, 700, (17, 21), (14, 20))}
    if elev not in levels:
        return None
    lo, up, tm, dm, (a1, a2), (b1, b2) = levels[elev]
    stab = temps[up] - temps[lo]
    moist = temps[tm] - dews[dm]
    sa = 1 if stab <= a1 else 2 if stab <= a2 else 3
    sb = 1 if moist <= b1 else 2 if moist <= b2 else 3
    total = sa + sb
    label = "very low" if total <= 3 else "low" if total == 4 else "moderate" if total == 5 else "high"
    return [total, label]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['low elevation sounding', ['low', {950: 13, 850: 9, 700: 3, 500: -20}, {850: 1, 700: -6}], [4, 'low']], ['low elevation sounding', ['low', {950: 12, 850: 1, 700: -5, 500: -24}, {850: -11, 700: -17}], [6, 'high']], ['low elevation sounding', ['low', {950: 13, 850: 8, 700: 3, 500: -22}, {850: -2, 700: -8}], [5, 'moderate']], ['low elevation sounding', ['low', {950: 18, 850: 10, 700: -4, 500: -26}, {850: -6, 700: -8}], [6, 'high']], ['low elevation sounding', ['low', {950: 15, 850: 10, 700: 6, 500: -6}, {850: 8, 700: 3}], [3, 'very low']], ['low elevation sounding', ['low', {950: 29, 850: 22, 700: 20, 500: 7}, {850: 14, 700: 14}], [4, 'low']], ['low elevation sounding', ['low', {950: 22, 850: 13, 700: 2, 500: -24}, {850: -1, 700: -17}], [6, 'high']], ['mid strong inversion', ['mid', {950: 10, 850: 4, 700: 12, 500: -8}, {850: 0, 700: 3}], [2, 'very low']]], [['low elevation sounding', ['low', {950: 18, 850: 10, 700: -4, 500: -26}, {850: -6, 700: -8}], [6, 'high']], ['low elevation sounding', ['low', {950: 13, 850: 13, 700: 2, 500: -19}, {850: 2, 700: -3}], [4, 'low']], ['low elevation sounding', ['low', {950: 13, 850: 1, 700: -9, 500: -31}, {850: -5, 700: -17}], [5, 'moderate']], ['low elevation sounding', ['low', {950: 24, 850: 21, 700: 12, 500: -12}, {850: 12, 700: -4}], [3, 'very low']], ['low elevation sounding', ['low', {950: 18, 850: 18, 700: 15, 500: -10}, {850: 16, 700: 7}], [2, 'very low']], ['low elevation sounding', ['low', {950: 18, 850: 18, 700: 16, 500: 2}, {850: 5, 700: 13}], [4, 'low']], ['low elevation sounding', ['low', {950: 26, 850: 27, 700: 19, 500: 0}, {850: 22, 700: 2}], [2, 'very low']], ['low surface inversion', ['low', {950: 12, 850: 18, 700: 6, 500: -14}, {850: 10, 700: -5}], [3, 'very low']]], [['low elevation sounding', ['low', {950: 22, 850: 13, 700: 2, 500: -24}, {850: -1, 700: -17}], [6, 'high']], ['mid elevation sounding', ['mid', {950: 23, 850: 23, 700: 17, 500: -2}, {850: 11, 700: 10}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 24, 850: 12, 700: 9, 500: -12}, {850: 8, 700: -6}], [2, 'very low']], ['mid elevation sounding', ['mid', {950: 18, 850: 7, 700: 5, 500: -20}, {850: -5, 700: -8}], [3, 'very low']], ['mid elevation sounding', ['mid', {950: 10, 850: 2, 700: -11, 500: -32}, {850: -9, 700: -26}], [5, 'moderate']], ['mid elevation sounding', ['mid', {950: 18, 850: 10, 700: 4, 500: -16}, {850: 4, 700: 3}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 30, 850: 18, 700: 4, 500: -12}, {850: 15, 700: -8}], [4, 'low']], ['high inversion aloft', ['high', {950: 10, 850: 4, 700: -30, 500: -12}, {850: 0, 700: -40}], [2, 'very low']]], [['mid elevation sounding', ['mid', {950: 23, 850: 23, 700: 17, 500: -2}, {850: 11, 700: 10}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 28, 850: 22, 700: 12, 500: -14}, {850: 11, 700: 4}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 13, 850: 15, 700: 11, 500: -13}, {850: 9, 700: 11}], [3, 'very low']], ['mid elevation sounding', ['mid', {950: 17, 850: 12, 700: -3, 500: -23}, {850: 4, 700: -8}], [5, 'moderate']], ['mid elevation sounding', ['mid', {950: 17, 850: 14, 700: 3, 500: -19}, {850: 4, 700: -6}], [5, 'moderate']], ['mid elevation sounding', ['mid', {950: 21, 850: 23, 700: 13, 500: -13}, {850: 18, 700: -3}], [3, 'very low']], ['mid elevation sounding', ['mid', {950: 30, 850: 27, 700: 20, 500: 1}, {850: 15, 700: 13}], [4, 'low']], ['mid strong inversion', ['mid', {950: 10, 850: 4, 700: 12, 500: -8}, {850: 0, 700: 3}], [2, 'very low']]], [['mid elevation sounding', ['mid', {950: 30, 850: 18, 700: 4, 500: -12}, {850: 15, 700: -8}], [4, 'low']], ['high elevation sounding', ['high', {950: 30, 850: 20, 700: 11, 500: -13}, {850: 10, 700: 9}], [4, 'low']], ['high elevation sounding', ['high', {950: 18, 850: 18, 700: 14, 500: -1}, {850: 17, 700: -8}], [4, 'low']], ['high elevation sounding', ['high', {950: 14, 850: 11, 700: 5, 500: -14}, {850: -3, 700: 1}], [3, 'very low']], ['high elevation sounding', ['high', {950: 27, 850: 18, 700: 16, 500: -8}, {850: 15, 700: 8}], [4, 'low']], ['high elevation sounding', ['high', {950: 21, 850: 11, 700: 3, 500: -11}, {850: -3, 700: -4}], [2, 'very low']], ['high elevation sounding', ['high', {950: 12, 850: 11, 700: -3, 500: -26}, {850: 6, 700: -7}], [4, 'low']], ['low surface inversion', ['low', {950: 12, 850: 18, 700: 6, 500: -14}, {850: 10, 700: -5}], [3, 'very low']]]]
for label, args, expected in fixtures[N - 1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
low elevation sounding	`[3, 'very low']`	`[4, 'low']`	Failed
low elevation sounding	`[4, 'low']`	`[6, 'high']`	Failed
low elevation sounding	`[4, 'low']`	`[5, 'moderate']`	Failed
low elevation sounding	`[4, 'low']`	`[6, 'high']`	Failed
low elevation sounding	`[2, 'very low']`	`[3, 'very low']`	Failed
low elevation sounding	`[3, 'very low']`	`[4, 'low']`	Failed
low elevation sounding	`[4, 'low']`	`[6, 'high']`	Failed
mid strong inversion	`[3, 'very low']`	`[2, 'very low']`	Failed

SHA-256 / 97233542c9e4a250b035cbf1fd7a24a98e70dcc7591b78b76f348b6feb1734a3

2 / The unsuccessful fix

Exit 1

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(elev, temps, dews):
    levels = {"low": (950, 850, 850, 850, (3, 7), (5, 9)),
              "mid": (850, 700, 850, 850, (5, 10), (5, 12)),
              "high": (700, 500, 700, 700, (17, 21), (14, 20))}
    if elev not in levels:
        return None
    lo, up, tm, dm, (a1, a2), (b1, b2) = levels[elev]
    stab = abs(temps[up] - temps[lo])
    moist = temps[tm] - dews[dm]
    sa = 1 if stab <= a1 else 2 if stab <= a2 else 3
    sb = 1 if moist <= b1 else 2 if moist <= b2 else 3
    total = sa + sb
    label = "very low" if total <= 3 else "low" if total == 4 else "moderate" if total == 5 else "high"
    return [total, label]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['low elevation sounding', ['low', {950: 13, 850: 9, 700: 3, 500: -20}, {850: 1, 700: -6}], [4, 'low']], ['low elevation sounding', ['low', {950: 12, 850: 1, 700: -5, 500: -24}, {850: -11, 700: -17}], [6, 'high']], ['low elevation sounding', ['low', {950: 13, 850: 8, 700: 3, 500: -22}, {850: -2, 700: -8}], [5, 'moderate']], ['low elevation sounding', ['low', {950: 18, 850: 10, 700: -4, 500: -26}, {850: -6, 700: -8}], [6, 'high']], ['low elevation sounding', ['low', {950: 15, 850: 10, 700: 6, 500: -6}, {850: 8, 700: 3}], [3, 'very low']], ['low elevation sounding', ['low', {950: 29, 850: 22, 700: 20, 500: 7}, {850: 14, 700: 14}], [4, 'low']], ['low elevation sounding', ['low', {950: 22, 850: 13, 700: 2, 500: -24}, {850: -1, 700: -17}], [6, 'high']], ['mid strong inversion', ['mid', {950: 10, 850: 4, 700: 12, 500: -8}, {850: 0, 700: 3}], [2, 'very low']]], [['low elevation sounding', ['low', {950: 18, 850: 10, 700: -4, 500: -26}, {850: -6, 700: -8}], [6, 'high']], ['low elevation sounding', ['low', {950: 13, 850: 13, 700: 2, 500: -19}, {850: 2, 700: -3}], [4, 'low']], ['low elevation sounding', ['low', {950: 13, 850: 1, 700: -9, 500: -31}, {850: -5, 700: -17}], [5, 'moderate']], ['low elevation sounding', ['low', {950: 24, 850: 21, 700: 12, 500: -12}, {850: 12, 700: -4}], [3, 'very low']], ['low elevation sounding', ['low', {950: 18, 850: 18, 700: 15, 500: -10}, {850: 16, 700: 7}], [2, 'very low']], ['low elevation sounding', ['low', {950: 18, 850: 18, 700: 16, 500: 2}, {850: 5, 700: 13}], [4, 'low']], ['low elevation sounding', ['low', {950: 26, 850: 27, 700: 19, 500: 0}, {850: 22, 700: 2}], [2, 'very low']], ['low surface inversion', ['low', {950: 12, 850: 18, 700: 6, 500: -14}, {850: 10, 700: -5}], [3, 'very low']]], [['low elevation sounding', ['low', {950: 22, 850: 13, 700: 2, 500: -24}, {850: -1, 700: -17}], [6, 'high']], ['mid elevation sounding', ['mid', {950: 23, 850: 23, 700: 17, 500: -2}, {850: 11, 700: 10}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 24, 850: 12, 700: 9, 500: -12}, {850: 8, 700: -6}], [2, 'very low']], ['mid elevation sounding', ['mid', {950: 18, 850: 7, 700: 5, 500: -20}, {850: -5, 700: -8}], [3, 'very low']], ['mid elevation sounding', ['mid', {950: 10, 850: 2, 700: -11, 500: -32}, {850: -9, 700: -26}], [5, 'moderate']], ['mid elevation sounding', ['mid', {950: 18, 850: 10, 700: 4, 500: -16}, {850: 4, 700: 3}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 30, 850: 18, 700: 4, 500: -12}, {850: 15, 700: -8}], [4, 'low']], ['high inversion aloft', ['high', {950: 10, 850: 4, 700: -30, 500: -12}, {850: 0, 700: -40}], [2, 'very low']]], [['mid elevation sounding', ['mid', {950: 23, 850: 23, 700: 17, 500: -2}, {850: 11, 700: 10}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 28, 850: 22, 700: 12, 500: -14}, {850: 11, 700: 4}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 13, 850: 15, 700: 11, 500: -13}, {850: 9, 700: 11}], [3, 'very low']], ['mid elevation sounding', ['mid', {950: 17, 850: 12, 700: -3, 500: -23}, {850: 4, 700: -8}], [5, 'moderate']], ['mid elevation sounding', ['mid', {950: 17, 850: 14, 700: 3, 500: -19}, {850: 4, 700: -6}], [5, 'moderate']], ['mid elevation sounding', ['mid', {950: 21, 850: 23, 700: 13, 500: -13}, {850: 18, 700: -3}], [3, 'very low']], ['mid elevation sounding', ['mid', {950: 30, 850: 27, 700: 20, 500: 1}, {850: 15, 700: 13}], [4, 'low']], ['mid strong inversion', ['mid', {950: 10, 850: 4, 700: 12, 500: -8}, {850: 0, 700: 3}], [2, 'very low']]], [['mid elevation sounding', ['mid', {950: 30, 850: 18, 700: 4, 500: -12}, {850: 15, 700: -8}], [4, 'low']], ['high elevation sounding', ['high', {950: 30, 850: 20, 700: 11, 500: -13}, {850: 10, 700: 9}], [4, 'low']], ['high elevation sounding', ['high', {950: 18, 850: 18, 700: 14, 500: -1}, {850: 17, 700: -8}], [4, 'low']], ['high elevation sounding', ['high', {950: 14, 850: 11, 700: 5, 500: -14}, {850: -3, 700: 1}], [3, 'very low']], ['high elevation sounding', ['high', {950: 27, 850: 18, 700: 16, 500: -8}, {850: 15, 700: 8}], [4, 'low']], ['high elevation sounding', ['high', {950: 21, 850: 11, 700: 3, 500: -11}, {850: -3, 700: -4}], [2, 'very low']], ['high elevation sounding', ['high', {950: 12, 850: 11, 700: -3, 500: -26}, {850: 6, 700: -7}], [4, 'low']], ['low surface inversion', ['low', {950: 12, 850: 18, 700: 6, 500: -14}, {850: 10, 700: -5}], [3, 'very low']]]]
for label, args, expected in fixtures[N - 1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
low elevation sounding	`[4, 'low']`	`[4, 'low']`	Passed
low elevation sounding	`[6, 'high']`	`[6, 'high']`	Passed
low elevation sounding	`[5, 'moderate']`	`[5, 'moderate']`	Passed
low elevation sounding	`[6, 'high']`	`[6, 'high']`	Passed
low elevation sounding	`[3, 'very low']`	`[3, 'very low']`	Passed
low elevation sounding	`[4, 'low']`	`[4, 'low']`	Passed
low elevation sounding	`[6, 'high']`	`[6, 'high']`	Passed
mid strong inversion	`[3, 'very low']`	`[2, 'very low']`	Failed

SHA-256 / 71d7c56af799ddf92eaa9516db581c2dd1e248a53484c29904752f0fcdcc1d41

3 / The verified repair

Exit 0

"""Failure Map reference implementation. Python standard library only."""
import json

N = 1
observations = []
def solve(elev, temps, dews):
    levels = {"low": (950, 850, 850, 850, (3, 7), (5, 9)),
              "mid": (850, 700, 850, 850, (5, 10), (5, 12)),
              "high": (700, 500, 700, 700, (17, 21), (14, 20))}
    if elev not in levels:
        return None
    lo, up, tm, dm, (a1, a2), (b1, b2) = levels[elev]
    stab = temps[lo] - temps[up]
    moist = temps[tm] - dews[dm]
    sa = 1 if stab <= a1 else 2 if stab <= a2 else 3
    sb = 1 if moist <= b1 else 2 if moist <= b2 else 3
    total = sa + sb
    label = "very low" if total <= 3 else "low" if total == 4 else "moderate" if total == 5 else "high"
    return [total, label]
def check(label, actual, expected):
    observations.append({"check": label, "actual": actual, "expected": expected, "passed": actual == expected})
fixtures = [[['low elevation sounding', ['low', {950: 13, 850: 9, 700: 3, 500: -20}, {850: 1, 700: -6}], [4, 'low']], ['low elevation sounding', ['low', {950: 12, 850: 1, 700: -5, 500: -24}, {850: -11, 700: -17}], [6, 'high']], ['low elevation sounding', ['low', {950: 13, 850: 8, 700: 3, 500: -22}, {850: -2, 700: -8}], [5, 'moderate']], ['low elevation sounding', ['low', {950: 18, 850: 10, 700: -4, 500: -26}, {850: -6, 700: -8}], [6, 'high']], ['low elevation sounding', ['low', {950: 15, 850: 10, 700: 6, 500: -6}, {850: 8, 700: 3}], [3, 'very low']], ['low elevation sounding', ['low', {950: 29, 850: 22, 700: 20, 500: 7}, {850: 14, 700: 14}], [4, 'low']], ['low elevation sounding', ['low', {950: 22, 850: 13, 700: 2, 500: -24}, {850: -1, 700: -17}], [6, 'high']], ['mid strong inversion', ['mid', {950: 10, 850: 4, 700: 12, 500: -8}, {850: 0, 700: 3}], [2, 'very low']]], [['low elevation sounding', ['low', {950: 18, 850: 10, 700: -4, 500: -26}, {850: -6, 700: -8}], [6, 'high']], ['low elevation sounding', ['low', {950: 13, 850: 13, 700: 2, 500: -19}, {850: 2, 700: -3}], [4, 'low']], ['low elevation sounding', ['low', {950: 13, 850: 1, 700: -9, 500: -31}, {850: -5, 700: -17}], [5, 'moderate']], ['low elevation sounding', ['low', {950: 24, 850: 21, 700: 12, 500: -12}, {850: 12, 700: -4}], [3, 'very low']], ['low elevation sounding', ['low', {950: 18, 850: 18, 700: 15, 500: -10}, {850: 16, 700: 7}], [2, 'very low']], ['low elevation sounding', ['low', {950: 18, 850: 18, 700: 16, 500: 2}, {850: 5, 700: 13}], [4, 'low']], ['low elevation sounding', ['low', {950: 26, 850: 27, 700: 19, 500: 0}, {850: 22, 700: 2}], [2, 'very low']], ['low surface inversion', ['low', {950: 12, 850: 18, 700: 6, 500: -14}, {850: 10, 700: -5}], [3, 'very low']]], [['low elevation sounding', ['low', {950: 22, 850: 13, 700: 2, 500: -24}, {850: -1, 700: -17}], [6, 'high']], ['mid elevation sounding', ['mid', {950: 23, 850: 23, 700: 17, 500: -2}, {850: 11, 700: 10}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 24, 850: 12, 700: 9, 500: -12}, {850: 8, 700: -6}], [2, 'very low']], ['mid elevation sounding', ['mid', {950: 18, 850: 7, 700: 5, 500: -20}, {850: -5, 700: -8}], [3, 'very low']], ['mid elevation sounding', ['mid', {950: 10, 850: 2, 700: -11, 500: -32}, {850: -9, 700: -26}], [5, 'moderate']], ['mid elevation sounding', ['mid', {950: 18, 850: 10, 700: 4, 500: -16}, {850: 4, 700: 3}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 30, 850: 18, 700: 4, 500: -12}, {850: 15, 700: -8}], [4, 'low']], ['high inversion aloft', ['high', {950: 10, 850: 4, 700: -30, 500: -12}, {850: 0, 700: -40}], [2, 'very low']]], [['mid elevation sounding', ['mid', {950: 23, 850: 23, 700: 17, 500: -2}, {850: 11, 700: 10}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 28, 850: 22, 700: 12, 500: -14}, {850: 11, 700: 4}], [4, 'low']], ['mid elevation sounding', ['mid', {950: 13, 850: 15, 700: 11, 500: -13}, {850: 9, 700: 11}], [3, 'very low']], ['mid elevation sounding', ['mid', {950: 17, 850: 12, 700: -3, 500: -23}, {850: 4, 700: -8}], [5, 'moderate']], ['mid elevation sounding', ['mid', {950: 17, 850: 14, 700: 3, 500: -19}, {850: 4, 700: -6}], [5, 'moderate']], ['mid elevation sounding', ['mid', {950: 21, 850: 23, 700: 13, 500: -13}, {850: 18, 700: -3}], [3, 'very low']], ['mid elevation sounding', ['mid', {950: 30, 850: 27, 700: 20, 500: 1}, {850: 15, 700: 13}], [4, 'low']], ['mid strong inversion', ['mid', {950: 10, 850: 4, 700: 12, 500: -8}, {850: 0, 700: 3}], [2, 'very low']]], [['mid elevation sounding', ['mid', {950: 30, 850: 18, 700: 4, 500: -12}, {850: 15, 700: -8}], [4, 'low']], ['high elevation sounding', ['high', {950: 30, 850: 20, 700: 11, 500: -13}, {850: 10, 700: 9}], [4, 'low']], ['high elevation sounding', ['high', {950: 18, 850: 18, 700: 14, 500: -1}, {850: 17, 700: -8}], [4, 'low']], ['high elevation sounding', ['high', {950: 14, 850: 11, 700: 5, 500: -14}, {850: -3, 700: 1}], [3, 'very low']], ['high elevation sounding', ['high', {950: 27, 850: 18, 700: 16, 500: -8}, {850: 15, 700: 8}], [4, 'low']], ['high elevation sounding', ['high', {950: 21, 850: 11, 700: 3, 500: -11}, {850: -3, 700: -4}], [2, 'very low']], ['high elevation sounding', ['high', {950: 12, 850: 11, 700: -3, 500: -26}, {850: 6, 700: -7}], [4, 'low']], ['low surface inversion', ['low', {950: 12, 850: 18, 700: 6, 500: -14}, {850: 10, 700: -5}], [3, 'very low']]]]
for label, args, expected in fixtures[N - 1]:
    check(label, solve(*args), expected)
print(json.dumps({"observations": observations, "passed": all(x["passed"] for x in observations)}, ensure_ascii=False))
raise SystemExit(0 if all(x["passed"] for x in observations) else 1)

Boundary fixture	Actual	Expected	Outcome
low elevation sounding	`[4, 'low']`	`[4, 'low']`	Passed
low elevation sounding	`[6, 'high']`	`[6, 'high']`	Passed
low elevation sounding	`[5, 'moderate']`	`[5, 'moderate']`	Passed
low elevation sounding	`[6, 'high']`	`[6, 'high']`	Passed
low elevation sounding	`[3, 'very low']`	`[3, 'very low']`	Passed
low elevation sounding	`[4, 'low']`	`[4, 'low']`	Passed
low elevation sounding	`[6, 'high']`	`[6, 'high']`	Passed
mid strong inversion	`[2, 'very low']`	`[2, 'very low']`	Passed

SHA-256 / baa3279cebbf7cd789cdfa3a83d1097ca350dfabcef7d7f308409ac57d70f2cc

Verification & scope

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.

Observations recorded using Python 3.12.14 at 2026-09-29T14:48:27.020005+00:00.

Case digest / 4f0a6ff7904d54f795dfa8fef082781bbe370b847ce45995a03fdf3c7f3360df