Edition 2026-09-24 The Ledger Archive API RSS Weather Trader
Milepost
1192

TheForecast Post

A chronicle of American weather and climate  ·  Thursday, 24 September 2026

The Ledger The Ledger MILEPOST 1192

The ledger, through September 24

Mean absolute temperature error runs 2.22°F at day 1 and 3.81°F at day 7, over 517,017 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 25–September 24, 2026.

LeadNDFDNBMpairs
Day 12.282.2271,990
Day 22.492.4271,761
Day 32.752.6471,016
Day 42.982.8770,781
Day 53.313.1570,260
Day 63.643.4969,876
Day 74.013.8156,708
Day 84.1134,625

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 35,996
August 25–September 24, 2026
day-3 mean absolute temperature error, NBM
Forecast Network verification ledger
2.64 °F of 35,620
August 25–September 24, 2026
day-5 mean absolute temperature error, NBM
Forecast Network verification ledger
3.15 °F of 35,695
August 25–September 24, 2026
day-7 mean absolute temperature error, NBM
Forecast Network verification ledger
3.81 °F of 35,544
August 25–September 24, 2026
day-1 mean absolute temperature error, NDFD
Forecast Network verification ledger
2.28 °F of 35,994
August 25–September 24, 2026
day-3 mean absolute temperature error, NDFD
Forecast Network verification ledger
2.75 °F of 35,396
August 25–September 24, 2026
day-5 mean absolute temperature error, NDFD
Forecast Network verification ledger
3.31 °F of 34,565
August 25–September 24, 2026
day-7 mean absolute temperature error, NDFD
Forecast Network verification ledger
4.01 °F of 21,164
August 25–September 24, 2026
Milepost
1192 · laid 2026-09-24T00:25:13Z
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
3976c1ddd30f4e484397a763f9ad824f13666d34d48a4c3072a89d16a7c61446
Machine
JSON