{ "number": 1125, "headline": "The ledger, through September 18", "standfirst": "Mean absolute temperature error runs 2.23\u00b0F at day 1 and 3.66\u00b0F at day 7, over 456,111 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": "2026-09-18", "published": "2026-09-18T00:25:13Z", "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 19\u2013September 18, 2026.

LeadNDFDNBMpairs
Day 12.282.2368,199
Day 22.482.4267,374
Day 32.722.6365,629
Day 42.962.8563,276
Day 53.243.1260,881
Day 63.533.4158,470
Day 73.823.6645,590
Day 8\u20143.9526,692

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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