The Ledger The Ledger
MILEPOST 1135
The ledger, through September 19
Mean absolute temperature error runs 2.23°F at day 1 and 3.68°F at day 7, over 470,383 settled forecast-observation pairs.
Every forecast this network publishes for a station with an ASOS report is compared against that report once the valid time has passed, and the residual is written down. This is the standing table for August 20–September 19, 2026.
| Lead | NDFD | NBM | pairs |
|---|---|---|---|
| Day 1 | 2.29 | 2.23 | 68,493 |
| Day 2 | 2.48 | 2.42 | 68,498 |
| Day 3 | 2.73 | 2.63 | 67,439 |
| Day 4 | 2.96 | 2.85 | 65,844 |
| Day 5 | 3.25 | 3.13 | 63,449 |
| Day 6 | 3.54 | 3.43 | 61,038 |
| Day 7 | 3.82 | 3.68 | 47,670 |
| Day 8 | — | 3.96 | 27,952 |
Mean absolute error, °F, temperature. ASOS reports at :53 and the forecast is stamped on the hour, so a forecast is paired with the nearest observation within 30 minutes and otherwise left unscored.
The numbers in this piece, with what they are measured against
| day-1 mean absolute temperature error, NBM Forecast Network verification ledger |
2.23 °F | of 34,961 August 20–September 19, 2026 |
| day-3 mean absolute temperature error, NBM Forecast Network verification ledger |
2.63 °F | of 33,902 August 20–September 19, 2026 |
| day-5 mean absolute temperature error, NBM Forecast Network verification ledger |
3.13 °F | of 31,580 August 20–September 19, 2026 |
| day-7 mean absolute temperature error, NBM Forecast Network verification ledger |
3.68 °F | of 29,167 August 20–September 19, 2026 |
| day-1 mean absolute temperature error, NDFD Forecast Network verification ledger |
2.29 °F | of 33,532 August 20–September 19, 2026 |
| day-3 mean absolute temperature error, NDFD Forecast Network verification ledger |
2.73 °F | of 33,537 August 20–September 19, 2026 |
| day-5 mean absolute temperature error, NDFD Forecast Network verification ledger |
3.25 °F | of 31,869 August 20–September 19, 2026 |
| day-7 mean absolute temperature error, NDFD Forecast Network verification ledger |
3.82 °F | of 18,503 August 20–September 19, 2026 |
- Milepost
- 1135 · laid 2026-09-19T00:25:16Z
- Desk
- ledger v1
- Method
- ASOS reports at :53 and the forecast is stamped on the hour, so a forecast is paired with the nearest observation within 30 minutes and otherwise left unscored.
- Source
- /home/maue/forecastpoints/data/verify/2026-08.ndjson
/home/maue/forecastpoints/data/verify/2026-09.ndjson - Digest
- a34508e4f255ff50dc538917297efdb15cf30c38100ad27bd2746739d92dc531
- Machine
- JSON