The Ledger The Ledger
MILEPOST 1229
The ledger, through September 28
Mean absolute temperature error runs 2.22°F at day 1 and 3.88°F at day 7, over 507,495 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 29–September 28, 2026.
| Lead | NDFD | NBM | pairs |
|---|---|---|---|
| Day 1 | 2.29 | 2.22 | 69,221 |
| Day 2 | 2.51 | 2.43 | 69,233 |
| Day 3 | 2.77 | 2.66 | 69,468 |
| Day 4 | 3.02 | 2.90 | 69,832 |
| Day 5 | 3.34 | 3.20 | 69,832 |
| Day 6 | 3.67 | 3.55 | 69,605 |
| Day 7 | 4.07 | 3.88 | 55,708 |
| Day 8 | — | 4.19 | 34,596 |
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 |
2.22 °F | of 34,307 August 29–September 28, 2026 |
| day-3 mean absolute temperature error, NBM Forecast Network verification ledger |
2.66 °F | of 34,552 August 29–September 28, 2026 |
| day-5 mean absolute temperature error, NBM Forecast Network verification ledger |
3.2 °F | of 34,916 August 29–September 28, 2026 |
| day-7 mean absolute temperature error, NBM Forecast Network verification ledger |
3.88 °F | of 34,540 August 29–September 28, 2026 |
| day-1 mean absolute temperature error, NDFD Forecast Network verification ledger |
2.29 °F | of 34,914 August 29–September 28, 2026 |
| day-3 mean absolute temperature error, NDFD Forecast Network verification ledger |
2.77 °F | of 34,916 August 29–September 28, 2026 |
| day-5 mean absolute temperature error, NDFD Forecast Network verification ledger |
3.34 °F | of 34,916 August 29–September 28, 2026 |
| day-7 mean absolute temperature error, NDFD Forecast Network verification ledger |
4.07 °F | of 21,168 August 29–September 28, 2026 |
- Milepost
- 1229 · laid 2026-09-28T00:25:12Z
- 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
- 38212097c80fd273e7d900f63f955c648b865618e5b669c01a74f14569a4c069
- Machine
- JSON