Methodology
This page details the methodology behind the Seattle Bleakness Index.
v1 Scoring Rubric (25 pts max)
Components & bins
| Component | How computed | Bins / Points | Max |
|---|---|---|---|
| GHI / shortwave (daylight avg) | Average of hourly shortwave_radiation between sunrise–sunset | 400+ W/m² = 0; 250–400 = 2; 125–250 = 4; below 125 = 6 | 6 |
| Precip duration (24h) | Count hours with precip >0.1 mm/hr | 0h=0; 1–3h=2; 4–8h=4; 8h+ = 6 | 6 |
| Wind gusts (daily max) | Max hourly wind_gusts_10m (mph) | below 20=0; 20–35=2; 35+ = 4 | 4 |
| Temp vs normal (daily high) | high_F minus daily normal_F (interpolated from Meteostat monthly) | within ±5°F=0; 6–15°F below=2; 15°F+ below=3 (ignore above-normal heat in v1) | 3 |
| Low cloud cover (daylight avg) | Avg hourly cloud_cover_low (%) in daylight | below 25%=0; 25–75%=1; 75%+=2 | 2 |
| Visibility (daylight avg) | Avg hourly visibility (mi) in daylight | 6+ mi=0; 2–6 mi=1; below 2 mi=2 | 2 |
Heavy precip kicker: If heavy precip hours (≥ 2.5 mm/hr): +2 pts if ≥2 hours, +1 pt if exactly 1 hour.
→ Total Max = 25 pts.
Scaling to 1–10
- Bleakness Index =
round(1 + 9*(raw_pts/25), 1), clamp to 1–10 - Daily Digit =
round(10 - 9*(raw_pts/25), 1), clamp to 1–10