{ "number": 1221, "headline": "The ledger, through September 27", "standfirst": "Mean absolute temperature error runs 2.22\u00b0F at day 1 and 3.87\u00b0F at day 7, over 522,450 settled forecast-observation pairs.", "desk": "ledger", "dateline": { "place": "The Ledger", "state": null, "lat": null, "lon": null, "site_key": null, "site_name": null, "site_url": null, "accent": null }, "edition": "2026-09-27", "published": "2026-09-27T00:25:32Z", "updated": null, "access": "free", "body_html": "

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 28\u2013September 27, 2026.

LeadNDFDNBMpairs
Day 12.282.2271,381
Day 22.512.4371,393
Day 32.772.6671,692
Day 43.012.8971,992
Day 53.333.1971,767
Day 63.673.5471,084
Day 74.063.8757,465
Day 8\u20144.1735,676

Mean absolute error, \u00b0F, 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.

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