{ "site": "forecastseason.com", "route": "08", "title": "The Seasonal Wire", "generated": "2026-10-16T18:52:14Z", "init": "2026-10", "init_label": "1 October 2026", "note": "Every outlook forecastseason.com publishes. Nothing is computed here: each figure is lifted from the route that published it, listed under endpoints. Probabilities are percent and 33.3 is climatology. Lead 1 is the initialisation's own month and is part elapsed.", "headline": "C3S multi-system puts S. America temperature at 74 percent likely above normal for November 2026 - the strongest tilt in this run", "subhead": "Its own reforecast beat climatology over 96 percent of that box; the three systems differ by 11 points over the United States in February 2027.", "lines": [ "C3S multi-system puts S. America temperature at 74 percent likely above normal for November 2026 - the strongest tilt in this run.", "Its own reforecast beat climatology over 96 percent of that box; the three systems differ by 11 points over the United States in February 2027.", "C3S multi-system takes 9 of 10 whole-month scorings on reforecast RPSS over land", "Skill decays with lead: over the United States, 54-61 percent of the box beat climatology at November 2026, 46-89 percent by March 2027" ], "wire": "/wire.txt", "period": { "months": [ "October 2026", "November 2026", "December 2026", "January 2027", "February 2027", "March 2027" ], "whole_months": [ "November 2026", "December 2026", "January 2027", "February 2027", "March 2027" ], "part_elapsed": [ "October 2026" ] }, "systems": [ { "key": "seas5", "name": "SEAS5", "route": "10", "href": "/probability/", "reforecast": "1993\u20132016", "reforecast_years": 24 }, { "key": "c3s", "name": "C3S multi-system", "route": "03", "href": "/multi-system/", "reforecast": "1993\u20132016", "reforecast_years": 24 }, { "key": "nmme", "name": "NMME", "route": "02", "href": "/nmme/", "reforecast": "1991\u20132016", "reforecast_years": 26 } ], "outlook": [ { "region": "conus", "label": "United States", "field": "t2m", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 44.2, "beats_clim_pct": 85.0 }, "c3s": { "p_above_pct": 43.9, "beats_clim_pct": 98.0 }, "nmme": { "p_above_pct": 40.5, "beats_clim_pct": 96.0 } }, { "region": "conus", "label": "United States", "field": "t2m", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 25.9, "beats_clim_pct": 54.0 }, "c3s": { "p_above_pct": 35.7, "beats_clim_pct": 60.0 }, "nmme": { "p_above_pct": 32.2, "beats_clim_pct": 61.0 } }, { "region": "conus", "label": "United States", "field": "t2m", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 37.4, "beats_clim_pct": 41.0 }, "c3s": { "p_above_pct": 37.6, "beats_clim_pct": 56.0 }, "nmme": { "p_above_pct": 35.0, "beats_clim_pct": 56.0 } }, { "region": "conus", "label": "United States", "field": "t2m", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 32.3, "beats_clim_pct": 47.0 }, "c3s": { "p_above_pct": 32.7, "beats_clim_pct": 72.0 }, "nmme": { "p_above_pct": 37.1, "beats_clim_pct": 42.0 } }, { "region": "conus", "label": "United States", "field": "t2m", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 24.3, "beats_clim_pct": 53.0 }, "c3s": { "p_above_pct": 27.1, "beats_clim_pct": 90.0 }, "nmme": { "p_above_pct": 35.8, "beats_clim_pct": 93.0 } }, { "region": "conus", "label": "United States", "field": "t2m", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 33.5, "beats_clim_pct": 46.0 }, "c3s": { "p_above_pct": 28.1, "beats_clim_pct": 89.0 }, "nmme": { "p_above_pct": 31.5, "beats_clim_pct": 64.0 } }, { "region": "conus", "label": "United States", "field": "precip", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 25.0, "beats_clim_pct": 78.0 }, "c3s": { "p_above_pct": 39.0, "beats_clim_pct": 89.0 }, "nmme": { "p_above_pct": 33.8, "beats_clim_pct": 76.0 } }, { "region": "conus", "label": "United States", "field": "precip", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 45.5, "beats_clim_pct": 41.0 }, "c3s": { "p_above_pct": 44.6, "beats_clim_pct": 60.0 }, "nmme": { "p_above_pct": 43.9, "beats_clim_pct": 52.0 } }, { "region": "conus", "label": "United States", "field": "precip", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 40.5, "beats_clim_pct": 47.0 }, "c3s": { "p_above_pct": 44.1, "beats_clim_pct": 61.0 }, "nmme": { "p_above_pct": 41.0, "beats_clim_pct": 61.0 } }, { "region": "conus", "label": "United States", "field": "precip", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 41.4, "beats_clim_pct": 37.0 }, "c3s": { "p_above_pct": 44.8, "beats_clim_pct": 67.0 }, "nmme": { "p_above_pct": 43.5, "beats_clim_pct": 52.0 } }, { "region": "conus", "label": "United States", "field": "precip", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 47.6, "beats_clim_pct": 42.0 }, "c3s": { "p_above_pct": 43.8, "beats_clim_pct": 61.0 }, "nmme": { "p_above_pct": 45.0, "beats_clim_pct": 62.0 } }, { "region": "conus", "label": "United States", "field": "precip", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 48.0, "beats_clim_pct": 43.0 }, "c3s": { "p_above_pct": 41.7, "beats_clim_pct": 56.0 }, "nmme": { "p_above_pct": 44.1, "beats_clim_pct": 45.0 } }, { "region": "europe", "label": "Europe", "field": "t2m", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 34.7, "beats_clim_pct": 77.0 }, "c3s": { "p_above_pct": 36.2, "beats_clim_pct": 81.0 }, "nmme": { "p_above_pct": 38.0, "beats_clim_pct": 82.0 } }, { "region": "europe", "label": "Europe", "field": "t2m", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 36.3, "beats_clim_pct": 38.0 }, "c3s": { "p_above_pct": 38.5, "beats_clim_pct": 70.0 }, "nmme": { "p_above_pct": 40.1, "beats_clim_pct": 68.0 } }, { "region": "europe", "label": "Europe", "field": "t2m", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 48.6, "beats_clim_pct": 46.0 }, "c3s": { "p_above_pct": 43.8, "beats_clim_pct": 74.0 }, "nmme": { "p_above_pct": 31.6, "beats_clim_pct": 42.0 } }, { "region": "europe", "label": "Europe", "field": "t2m", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 46.6, "beats_clim_pct": 29.0 }, "c3s": { "p_above_pct": 44.6, "beats_clim_pct": 44.0 }, "nmme": { "p_above_pct": 45.7, "beats_clim_pct": 19.0 } }, { "region": "europe", "label": "Europe", "field": "t2m", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 45.5, "beats_clim_pct": 34.0 }, "c3s": { "p_above_pct": 42.9, "beats_clim_pct": 82.0 }, "nmme": { "p_above_pct": 39.8, "beats_clim_pct": 28.0 } }, { "region": "europe", "label": "Europe", "field": "t2m", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 38.8, "beats_clim_pct": 47.0 }, "c3s": { "p_above_pct": 36.9, "beats_clim_pct": 68.0 }, "nmme": { "p_above_pct": 41.4, "beats_clim_pct": 62.0 } }, { "region": "europe", "label": "Europe", "field": "precip", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 37.3, "beats_clim_pct": 64.0 }, "c3s": { "p_above_pct": 38.8, "beats_clim_pct": 86.0 }, "nmme": { "p_above_pct": 36.1, "beats_clim_pct": 67.0 } }, { "region": "europe", "label": "Europe", "field": "precip", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 36.8, "beats_clim_pct": 29.0 }, "c3s": { "p_above_pct": 38.0, "beats_clim_pct": 47.0 }, "nmme": { "p_above_pct": 34.0, "beats_clim_pct": 35.0 } }, { "region": "europe", "label": "Europe", "field": "precip", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 35.7, "beats_clim_pct": 26.0 }, "c3s": { "p_above_pct": 38.7, "beats_clim_pct": 40.0 }, "nmme": { "p_above_pct": 37.0, "beats_clim_pct": 29.0 } }, { "region": "europe", "label": "Europe", "field": "precip", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 40.3, "beats_clim_pct": 32.0 }, "c3s": { "p_above_pct": 39.4, "beats_clim_pct": 64.0 }, "nmme": { "p_above_pct": 38.3, "beats_clim_pct": 43.0 } }, { "region": "europe", "label": "Europe", "field": "precip", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 46.1, "beats_clim_pct": 27.0 }, "c3s": { "p_above_pct": 42.3, "beats_clim_pct": 59.0 }, "nmme": { "p_above_pct": 38.2, "beats_clim_pct": 38.0 } }, { "region": "europe", "label": "Europe", "field": "precip", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 36.8, "beats_clim_pct": 38.0 }, "c3s": { "p_above_pct": 40.8, "beats_clim_pct": 46.0 }, "nmme": { "p_above_pct": 39.8, "beats_clim_pct": 42.0 } }, { "region": "asia", "label": "Asia", "field": "t2m", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 41.4, "beats_clim_pct": 94.0 }, "c3s": { "p_above_pct": 47.9, "beats_clim_pct": 99.0 }, "nmme": { "p_above_pct": 38.9, "beats_clim_pct": 95.0 } }, { "region": "asia", "label": "Asia", "field": "t2m", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 40.5, "beats_clim_pct": 42.0 }, "c3s": { "p_above_pct": 47.4, "beats_clim_pct": 66.0 }, "nmme": { "p_above_pct": 38.0, "beats_clim_pct": 53.0 } }, { "region": "asia", "label": "Asia", "field": "t2m", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 39.5, "beats_clim_pct": 51.0 }, "c3s": { "p_above_pct": 44.4, "beats_clim_pct": 74.0 }, "nmme": { "p_above_pct": 37.4, "beats_clim_pct": 48.0 } }, { "region": "asia", "label": "Asia", "field": "t2m", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 47.5, "beats_clim_pct": 40.0 }, "c3s": { "p_above_pct": 47.7, "beats_clim_pct": 65.0 }, "nmme": { "p_above_pct": 40.8, "beats_clim_pct": 52.0 } }, { "region": "asia", "label": "Asia", "field": "t2m", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 50.5, "beats_clim_pct": 51.0 }, "c3s": { "p_above_pct": 52.0, "beats_clim_pct": 83.0 }, "nmme": { "p_above_pct": 44.2, "beats_clim_pct": 56.0 } }, { "region": "asia", "label": "Asia", "field": "t2m", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 39.7, "beats_clim_pct": 52.0 }, "c3s": { "p_above_pct": 48.7, "beats_clim_pct": 85.0 }, "nmme": { "p_above_pct": 46.4, "beats_clim_pct": 70.0 } }, { "region": "asia", "label": "Asia", "field": "precip", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 41.0, "beats_clim_pct": 71.0 }, "c3s": { "p_above_pct": 40.1, "beats_clim_pct": 78.0 }, "nmme": { "p_above_pct": 37.0, "beats_clim_pct": 72.0 } }, { "region": "asia", "label": "Asia", "field": "precip", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 39.1, "beats_clim_pct": 26.0 }, "c3s": { "p_above_pct": 42.9, "beats_clim_pct": 43.0 }, "nmme": { "p_above_pct": 36.8, "beats_clim_pct": 39.0 } }, { "region": "asia", "label": "Asia", "field": "precip", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 41.4, "beats_clim_pct": 30.0 }, "c3s": { "p_above_pct": 42.2, "beats_clim_pct": 50.0 }, "nmme": { "p_above_pct": 38.4, "beats_clim_pct": 41.0 } }, { "region": "asia", "label": "Asia", "field": "precip", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 41.8, "beats_clim_pct": 29.0 }, "c3s": { "p_above_pct": 41.8, "beats_clim_pct": 38.0 }, "nmme": { "p_above_pct": 40.1, "beats_clim_pct": 27.0 } }, { "region": "asia", "label": "Asia", "field": "precip", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 42.7, "beats_clim_pct": 30.0 }, "c3s": { "p_above_pct": 41.8, "beats_clim_pct": 51.0 }, "nmme": { "p_above_pct": 39.6, "beats_clim_pct": 33.0 } }, { "region": "asia", "label": "Asia", "field": "precip", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 40.8, "beats_clim_pct": 28.0 }, "c3s": { "p_above_pct": 41.9, "beats_clim_pct": 47.0 }, "nmme": { "p_above_pct": 39.6, "beats_clim_pct": 36.0 } }, { "region": "africa", "label": "Africa", "field": "t2m", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 46.7, "beats_clim_pct": 91.0 }, "c3s": { "p_above_pct": 59.7, "beats_clim_pct": 99.0 }, "nmme": { "p_above_pct": 46.2, "beats_clim_pct": 98.0 } }, { "region": "africa", "label": "Africa", "field": "t2m", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 59.0, "beats_clim_pct": 56.0 }, "c3s": { "p_above_pct": 58.3, "beats_clim_pct": 81.0 }, "nmme": { "p_above_pct": 50.1, "beats_clim_pct": 82.0 } }, { "region": "africa", "label": "Africa", "field": "t2m", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 63.0, "beats_clim_pct": 65.0 }, "c3s": { "p_above_pct": 62.7, "beats_clim_pct": 81.0 }, "nmme": { "p_above_pct": 61.0, "beats_clim_pct": 71.0 } }, { "region": "africa", "label": "Africa", "field": "t2m", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 73.5, "beats_clim_pct": 52.0 }, "c3s": { "p_above_pct": 69.6, "beats_clim_pct": 72.0 }, "nmme": { "p_above_pct": 61.3, "beats_clim_pct": 67.0 } }, { "region": "africa", "label": "Africa", "field": "t2m", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 74.8, "beats_clim_pct": 73.0 }, "c3s": { "p_above_pct": 75.2, "beats_clim_pct": 91.0 }, "nmme": { "p_above_pct": 62.8, "beats_clim_pct": 88.0 } }, { "region": "africa", "label": "Africa", "field": "t2m", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 71.7, "beats_clim_pct": 67.0 }, "c3s": { "p_above_pct": 74.3, "beats_clim_pct": 74.0 }, "nmme": { "p_above_pct": 64.4, "beats_clim_pct": 79.0 } }, { "region": "africa", "label": "Africa", "field": "precip", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 52.9, "beats_clim_pct": 51.0 }, "c3s": { "p_above_pct": 45.5, "beats_clim_pct": 59.0 }, "nmme": { "p_above_pct": 37.8, "beats_clim_pct": 50.0 } }, { "region": "africa", "label": "Africa", "field": "precip", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 34.7, "beats_clim_pct": 31.0 }, "c3s": { "p_above_pct": 40.4, "beats_clim_pct": 40.0 }, "nmme": { "p_above_pct": 39.6, "beats_clim_pct": 33.0 } }, { "region": "africa", "label": "Africa", "field": "precip", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 30.7, "beats_clim_pct": 30.0 }, "c3s": { "p_above_pct": 34.8, "beats_clim_pct": 34.0 }, "nmme": { "p_above_pct": 36.3, "beats_clim_pct": 30.0 } }, { "region": "africa", "label": "Africa", "field": "precip", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 33.0, "beats_clim_pct": 18.0 }, "c3s": { "p_above_pct": 33.0, "beats_clim_pct": 32.0 }, "nmme": { "p_above_pct": 37.1, "beats_clim_pct": 23.0 } }, { "region": "africa", "label": "Africa", "field": "precip", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 32.6, "beats_clim_pct": 18.0 }, "c3s": { "p_above_pct": 33.9, "beats_clim_pct": 27.0 }, "nmme": { "p_above_pct": 33.6, "beats_clim_pct": 26.0 } }, { "region": "africa", "label": "Africa", "field": "precip", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 30.2, "beats_clim_pct": 20.0 }, "c3s": { "p_above_pct": 33.0, "beats_clim_pct": 24.0 }, "nmme": { "p_above_pct": 37.4, "beats_clim_pct": 25.0 } }, { "region": "samerica", "label": "S. America", "field": "t2m", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 67.2, "beats_clim_pct": 95.0 }, "c3s": { "p_above_pct": 68.7, "beats_clim_pct": 100.0 }, "nmme": { "p_above_pct": 59.6, "beats_clim_pct": 99.0 } }, { "region": "samerica", "label": "S. America", "field": "t2m", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 78.4, "beats_clim_pct": 89.0 }, "c3s": { "p_above_pct": 74.0, "beats_clim_pct": 96.0 }, "nmme": { "p_above_pct": 66.4, "beats_clim_pct": 94.0 } }, { "region": "samerica", "label": "S. America", "field": "t2m", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 79.2, "beats_clim_pct": 68.0 }, "c3s": { "p_above_pct": 77.7, "beats_clim_pct": 85.0 }, "nmme": { "p_above_pct": 74.8, "beats_clim_pct": 77.0 } }, { "region": "samerica", "label": "S. America", "field": "t2m", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 82.3, "beats_clim_pct": 80.0 }, "c3s": { "p_above_pct": 80.6, "beats_clim_pct": 92.0 }, "nmme": { "p_above_pct": 78.6, "beats_clim_pct": 92.0 } }, { "region": "samerica", "label": "S. America", "field": "t2m", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 82.8, "beats_clim_pct": 86.0 }, "c3s": { "p_above_pct": 82.0, "beats_clim_pct": 94.0 }, "nmme": { "p_above_pct": 78.9, "beats_clim_pct": 92.0 } }, { "region": "samerica", "label": "S. America", "field": "t2m", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 83.2, "beats_clim_pct": 78.0 }, "c3s": { "p_above_pct": 81.4, "beats_clim_pct": 88.0 }, "nmme": { "p_above_pct": 78.3, "beats_clim_pct": 78.0 } }, { "region": "samerica", "label": "S. America", "field": "precip", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 31.0, "beats_clim_pct": 82.0 }, "c3s": { "p_above_pct": 30.1, "beats_clim_pct": 89.0 }, "nmme": { "p_above_pct": 30.5, "beats_clim_pct": 80.0 } }, { "region": "samerica", "label": "S. America", "field": "precip", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 26.7, "beats_clim_pct": 68.0 }, "c3s": { "p_above_pct": 27.7, "beats_clim_pct": 74.0 }, "nmme": { "p_above_pct": 32.4, "beats_clim_pct": 62.0 } }, { "region": "samerica", "label": "S. America", "field": "precip", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 28.0, "beats_clim_pct": 59.0 }, "c3s": { "p_above_pct": 26.4, "beats_clim_pct": 79.0 }, "nmme": { "p_above_pct": 24.7, "beats_clim_pct": 55.0 } }, { "region": "samerica", "label": "S. America", "field": "precip", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 30.8, "beats_clim_pct": 46.0 }, "c3s": { "p_above_pct": 27.4, "beats_clim_pct": 67.0 }, "nmme": { "p_above_pct": 25.7, "beats_clim_pct": 59.0 } }, { "region": "samerica", "label": "S. America", "field": "precip", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 31.1, "beats_clim_pct": 55.0 }, "c3s": { "p_above_pct": 28.8, "beats_clim_pct": 69.0 }, "nmme": { "p_above_pct": 26.8, "beats_clim_pct": 51.0 } }, { "region": "samerica", "label": "S. America", "field": "precip", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 33.7, "beats_clim_pct": 36.0 }, "c3s": { "p_above_pct": 31.7, "beats_clim_pct": 57.0 }, "nmme": { "p_above_pct": 32.2, "beats_clim_pct": 39.0 } }, { "region": "oceania", "label": "Oceania", "field": "t2m", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 22.1, "beats_clim_pct": 98.0 }, "c3s": { "p_above_pct": 42.6, "beats_clim_pct": 100.0 }, "nmme": { "p_above_pct": 37.2, "beats_clim_pct": 99.0 } }, { "region": "oceania", "label": "Oceania", "field": "t2m", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 39.8, "beats_clim_pct": 89.0 }, "c3s": { "p_above_pct": 42.8, "beats_clim_pct": 95.0 }, "nmme": { "p_above_pct": 40.8, "beats_clim_pct": 89.0 } }, { "region": "oceania", "label": "Oceania", "field": "t2m", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 45.9, "beats_clim_pct": 79.0 }, "c3s": { "p_above_pct": 47.6, "beats_clim_pct": 96.0 }, "nmme": { "p_above_pct": 51.3, "beats_clim_pct": 91.0 } }, { "region": "oceania", "label": "Oceania", "field": "t2m", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 57.5, "beats_clim_pct": 44.0 }, "c3s": { "p_above_pct": 53.8, "beats_clim_pct": 54.0 }, "nmme": { "p_above_pct": 57.1, "beats_clim_pct": 37.0 } }, { "region": "oceania", "label": "Oceania", "field": "t2m", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 59.0, "beats_clim_pct": 76.0 }, "c3s": { "p_above_pct": 55.9, "beats_clim_pct": 85.0 }, "nmme": { "p_above_pct": 58.8, "beats_clim_pct": 86.0 } }, { "region": "oceania", "label": "Oceania", "field": "t2m", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 57.0, "beats_clim_pct": 77.0 }, "c3s": { "p_above_pct": 57.0, "beats_clim_pct": 88.0 }, "nmme": { "p_above_pct": 58.5, "beats_clim_pct": 71.0 } }, { "region": "oceania", "label": "Oceania", "field": "precip", "month": "October 2026", "lead": 0, "part_elapsed": true, "seas5": { "p_above_pct": 46.2, "beats_clim_pct": 71.0 }, "c3s": { "p_above_pct": 38.7, "beats_clim_pct": 81.0 }, "nmme": { "p_above_pct": 43.9, "beats_clim_pct": 83.0 } }, { "region": "oceania", "label": "Oceania", "field": "precip", "month": "November 2026", "lead": 1, "part_elapsed": false, "seas5": { "p_above_pct": 34.4, "beats_clim_pct": 57.0 }, "c3s": { "p_above_pct": 39.4, "beats_clim_pct": 68.0 }, "nmme": { "p_above_pct": 33.8, "beats_clim_pct": 65.0 } }, { "region": "oceania", "label": "Oceania", "field": "precip", "month": "December 2026", "lead": 2, "part_elapsed": false, "seas5": { "p_above_pct": 37.3, "beats_clim_pct": 56.0 }, "c3s": { "p_above_pct": 38.2, "beats_clim_pct": 74.0 }, "nmme": { "p_above_pct": 32.4, "beats_clim_pct": 63.0 } }, { "region": "oceania", "label": "Oceania", "field": "precip", "month": "January 2027", "lead": 3, "part_elapsed": false, "seas5": { "p_above_pct": 31.4, "beats_clim_pct": 38.0 }, "c3s": { "p_above_pct": 33.8, "beats_clim_pct": 56.0 }, "nmme": { "p_above_pct": 32.4, "beats_clim_pct": 36.0 } }, { "region": "oceania", "label": "Oceania", "field": "precip", "month": "February 2027", "lead": 4, "part_elapsed": false, "seas5": { "p_above_pct": 31.7, "beats_clim_pct": 57.0 }, "c3s": { "p_above_pct": 31.6, "beats_clim_pct": 70.0 }, "nmme": { "p_above_pct": 30.4, "beats_clim_pct": 47.0 } }, { "region": "oceania", "label": "Oceania", "field": "precip", "month": "March 2027", "lead": 5, "part_elapsed": false, "seas5": { "p_above_pct": 37.2, "beats_clim_pct": 51.0 }, "c3s": { "p_above_pct": 36.3, "beats_clim_pct": 78.0 }, "nmme": { "p_above_pct": 35.5, "beats_clim_pct": 59.0 } } ], "verification": { "metric": "rpss_land", "note": "Ranked probability skill score of each system's own reforecast against ERA5, area-weighted over land. Zero is climatology. The reforecast periods differ, so a comparison within one system is exact and one across systems is close but not matched.", "best": "c3s", "whole_month_scorings": 10, "wins": { "seas5": 0, "c3s": 9, "nmme": 1 }, "by_lead": [ { "system": "seas5", "field": "t2m", "month": "October 2026", "lead": 0, "part_elapsed": true, "rpss_land": 0.248, "beats_clim_pct": 91.0 }, { "system": "c3s", "field": "t2m", "month": "October 2026", "lead": 0, "part_elapsed": true, "rpss_land": 0.2682, "beats_clim_pct": 97.0 }, { "system": "nmme", "field": "t2m", "month": "October 2026", "lead": 0, "part_elapsed": true, "rpss_land": 0.2556, "beats_clim_pct": 96.0 }, { "system": "seas5", "field": "t2m", "month": "November 2026", "lead": 1, "part_elapsed": false, "rpss_land": 0.056, "beats_clim_pct": 61.0 }, { "system": "c3s", "field": "t2m", "month": "November 2026", "lead": 1, "part_elapsed": false, "rpss_land": 0.0944, "beats_clim_pct": 78.0 }, { "system": "nmme", "field": "t2m", "month": "November 2026", "lead": 1, "part_elapsed": false, "rpss_land": 0.0958, "beats_clim_pct": 72.0 }, { "system": "seas5", "field": "t2m", "month": "December 2026", "lead": 2, "part_elapsed": false, "rpss_land": 0.042, "beats_clim_pct": 60.0 }, { "system": "c3s", "field": "t2m", "month": "December 2026", "lead": 2, "part_elapsed": false, "rpss_land": 0.0762, "beats_clim_pct": 78.0 }, { "system": "nmme", "field": "t2m", "month": "December 2026", "lead": 2, "part_elapsed": false, "rpss_land": 0.0541, "beats_clim_pct": 66.0 }, { "system": "seas5", "field": "t2m", "month": "January 2027", "lead": 3, "part_elapsed": false, "rpss_land": 0.032, "beats_clim_pct": 51.0 }, { "system": "c3s", "field": "t2m", "month": "January 2027", "lead": 3, "part_elapsed": false, "rpss_land": 0.0816, "beats_clim_pct": 71.0 }, { "system": "nmme", "field": "t2m", "month": "January 2027", "lead": 3, "part_elapsed": false, "rpss_land": 0.0588, "beats_clim_pct": 60.0 }, { "system": "seas5", "field": "t2m", "month": "February 2027", "lead": 4, "part_elapsed": false, "rpss_land": 0.074, "beats_clim_pct": 64.0 }, { "system": "c3s", "field": "t2m", "month": "February 2027", "lead": 4, "part_elapsed": false, "rpss_land": 0.1172, "beats_clim_pct": 87.0 }, { "system": "nmme", "field": "t2m", "month": "February 2027", "lead": 4, "part_elapsed": false, "rpss_land": 0.1034, "beats_clim_pct": 77.0 }, { "system": "seas5", "field": "t2m", "month": "March 2027", "lead": 5, "part_elapsed": false, "rpss_land": 0.064, "beats_clim_pct": 61.0 }, { "system": "c3s", "field": "t2m", "month": "March 2027", "lead": 5, "part_elapsed": false, "rpss_land": 0.1019, "beats_clim_pct": 81.0 }, { "system": "nmme", "field": "t2m", "month": "March 2027", "lead": 5, "part_elapsed": false, "rpss_land": 0.083, "beats_clim_pct": 73.0 }, { "system": "seas5", "field": "precip", "month": "October 2026", "lead": 0, "part_elapsed": true, "rpss_land": 0.148, "beats_clim_pct": 67.0 }, { "system": "c3s", "field": "precip", "month": "October 2026", "lead": 0, "part_elapsed": true, "rpss_land": 0.1542, "beats_clim_pct": 76.0 }, { "system": "nmme", "field": "precip", "month": "October 2026", "lead": 0, "part_elapsed": true, "rpss_land": 0.1139, "beats_clim_pct": 67.0 }, { "system": "seas5", "field": "precip", "month": "November 2026", "lead": 1, "part_elapsed": false, "rpss_land": 0.004, "beats_clim_pct": 39.0 }, { "system": "c3s", "field": "precip", "month": "November 2026", "lead": 1, "part_elapsed": false, "rpss_land": 0.0416, "beats_clim_pct": 52.0 }, { "system": "nmme", "field": "precip", "month": "November 2026", "lead": 1, "part_elapsed": false, "rpss_land": 0.0172, "beats_clim_pct": 45.0 }, { "system": "seas5", "field": "precip", "month": "December 2026", "lead": 2, "part_elapsed": false, "rpss_land": 0.006, "beats_clim_pct": 39.0 }, { "system": "c3s", "field": "precip", "month": "December 2026", "lead": 2, "part_elapsed": false, "rpss_land": 0.0394, "beats_clim_pct": 53.0 }, { "system": "nmme", "field": "precip", "month": "December 2026", "lead": 2, "part_elapsed": false, "rpss_land": 0.0198, "beats_clim_pct": 46.0 }, { "system": "seas5", "field": "precip", "month": "January 2027", "lead": 3, "part_elapsed": false, "rpss_land": -0.014, "beats_clim_pct": 31.0 }, { "system": "c3s", "field": "precip", "month": "January 2027", "lead": 3, "part_elapsed": false, "rpss_land": 0.0288, "beats_clim_pct": 48.0 }, { "system": "nmme", "field": "precip", "month": "January 2027", "lead": 3, "part_elapsed": false, "rpss_land": 0.0033, "beats_clim_pct": 36.0 }, { "system": "seas5", "field": "precip", "month": "February 2027", "lead": 4, "part_elapsed": false, "rpss_land": -0.007, "beats_clim_pct": 34.0 }, { "system": "c3s", "field": "precip", "month": "February 2027", "lead": 4, "part_elapsed": false, "rpss_land": 0.0253, "beats_clim_pct": 50.0 }, { "system": "nmme", "field": "precip", "month": "February 2027", "lead": 4, "part_elapsed": false, "rpss_land": 0.0065, "beats_clim_pct": 40.0 }, { "system": "seas5", "field": "precip", "month": "March 2027", "lead": 5, "part_elapsed": false, "rpss_land": -0.017, "beats_clim_pct": 33.0 }, { "system": "c3s", "field": "precip", "month": "March 2027", "lead": 5, "part_elapsed": false, "rpss_land": 0.0122, "beats_clim_pct": 48.0 }, { "system": "nmme", "field": "precip", "month": "March 2027", "lead": 5, "part_elapsed": false, "rpss_land": -0.0076, "beats_clim_pct": 37.0 } ], "pooling": [ { "system": "c3s", "pooled": 10, "unit": "systems", "consensus_beats_best_member": 10, "of": 10, "rainfall_gains": 5, "rainfall_of": 5 }, { "system": "nmme", "pooled": 5, "unit": "models", "consensus_beats_best_member": 6, "of": 10, "rainfall_gains": 2, "rainfall_of": 5 } ], "adjudication": { "note": "Where the two multi-models disagree on the tilt, which one's own reforecast beat climatology over more of that box.", "region_months": 60, "wins": { "c3s": 50, "nmme": 7, "tie": 3 } } }, "analog": { "note": "This site's own forecast. A three-month anomaly in degrees, NOT a tercile probability, and therefore not comparable with the outlook above. signal_c is the anomaly with the warming trend removed.", "predictor": "July\u2013August\u2013September 2026", "href": "/analogs/", "regions": [ { "region": "conus", "label": "United States", "field": "t2m", "season": "OND 2026", "anom_c": 1.42, "signal_c": 0.99, "skilful_pct": 31.0 }, { "region": "europe", "label": "Europe", "field": "t2m", "season": "OND 2026", "anom_c": 0.89, "signal_c": 0.28, "skilful_pct": 45.0 }, { "region": "asia", "label": "Asia", "field": "t2m", "season": "OND 2026", "anom_c": -0.08, "signal_c": -0.62, "skilful_pct": 52.0 }, { "region": "africa", "label": "Africa", "field": "t2m", "season": "OND 2026", "anom_c": 1.14, "signal_c": 0.59, "skilful_pct": 76.0 }, { "region": "samerica", "label": "S. America", "field": "t2m", "season": "OND 2026", "anom_c": 0.94, "signal_c": 0.6, "skilful_pct": 81.0 }, { "region": "oceania", "label": "Oceania", "field": "t2m", "season": "OND 2026", "anom_c": 1.05, "signal_c": 0.86, "skilful_pct": 92.0 }, { "region": "conus", "label": "United States", "field": "t2m", "season": "NDJ 2027", "anom_c": 1.83, "signal_c": 1.32, "skilful_pct": 32.0 }, { "region": "europe", "label": "Europe", "field": "t2m", "season": "NDJ 2027", "anom_c": 0.28, "signal_c": -0.46, "skilful_pct": 15.0 }, { "region": "asia", "label": "Asia", "field": "t2m", "season": "NDJ 2027", "anom_c": 0.02, "signal_c": -0.49, "skilful_pct": 38.0 }, { "region": "africa", "label": "Africa", "field": "t2m", "season": "NDJ 2027", "anom_c": 0.94, "signal_c": 0.38, "skilful_pct": 57.0 }, { "region": "samerica", "label": "S. America", "field": "t2m", "season": "NDJ 2027", "anom_c": 1.0, "signal_c": 0.66, "skilful_pct": 89.0 }, { "region": "oceania", "label": "Oceania", "field": "t2m", "season": "NDJ 2027", "anom_c": 1.26, "signal_c": 1.08, "skilful_pct": 76.0 }, { "region": "conus", "label": "United States", "field": "t2m", "season": "DJF 2027", "anom_c": 2.12, "signal_c": 1.65, "skilful_pct": 27.0 }, { "region": "europe", "label": "Europe", "field": "t2m", "season": "DJF 2027", "anom_c": 0.29, "signal_c": -0.58, "skilful_pct": 4.0 }, { "region": "asia", "label": "Asia", "field": "t2m", "season": "DJF 2027", "anom_c": 1.21, "signal_c": 0.76, "skilful_pct": 30.0 }, { "region": "africa", "label": "Africa", "field": "t2m", "season": "DJF 2027", "anom_c": 1.26, "signal_c": 0.7, "skilful_pct": 48.0 }, { "region": "samerica", "label": "S. America", "field": "t2m", "season": "DJF 2027", "anom_c": 1.17, "signal_c": 0.83, "skilful_pct": 85.0 }, { "region": "oceania", "label": "Oceania", "field": "t2m", "season": "DJF 2027", "anom_c": 1.09, "signal_c": 0.82, "skilful_pct": 75.0 }, { "region": "conus", "label": "United States", "field": "t2m", "season": "JFM 2027", "anom_c": 1.94, "signal_c": 1.29, "skilful_pct": 27.0 }, { "region": "europe", "label": "Europe", "field": "t2m", "season": "JFM 2027", "anom_c": 0.79, "signal_c": -0.18, "skilful_pct": 2.0 }, { "region": "asia", "label": "Asia", "field": "t2m", "season": "JFM 2027", "anom_c": 1.68, "signal_c": 1.16, "skilful_pct": 37.0 }, { "region": "africa", "label": "Africa", "field": "t2m", "season": "JFM 2027", "anom_c": 1.32, "signal_c": 0.75, "skilful_pct": 49.0 }, { "region": "samerica", "label": "S. 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America", "field": "tp", "season": "FMA 2027", "anom_c": -13.57, "signal_c": -12.58, "skilful_pct": 30.0 }, { "region": "oceania", "label": "Oceania", "field": "tp", "season": "FMA 2027", "anom_c": 8.48, "signal_c": 4.91, "skilful_pct": 52.0 } ] }, "cities": { "n": 40, "href": "/cities/", "url": "/assets/cities/cities.json", "note": "Each briefing carries the reforecast skill of its own gridcell; a null rainfall figure means the climatology there is too dry for a tercile to mean anything, and is not a zero." }, "regimes": { "note": "Share of the 51 members' days in each of the seven Euro-Atlantic weather regimes per target month, against the model's own climatological share. rpss at or below zero means that row's tilt has never verified and should not be acted on.", "href": "/regimes/", "names": [ "AT", "EuBL", "ZO", "ScTr", "ScBL", "AR", "GL" ], "long_names": { "AT": "Atlantic trough", "EuBL": "European blocking", "ZO": "Zonal (NAO+)", "ScTr": "Scandinavian trough", "ScBL": "Scandinavian blocking", "AR": "Atlantic ridge", "GL": "Greenland blocking (NAO\u2212)" }, "monthly": [ { "month": "2026-10", "part_elapsed": true, "regimes": { "AT": { "fc_pct": 8.3, "clim_pct": 14.4, "rpss": -0.113, "acc": 0.306 }, "EuBL": { "fc_pct": 21.8, "clim_pct": 15.3, "rpss": 0.208, "acc": 0.432 }, "ZO": { "fc_pct": 31.7, "clim_pct": 13.1, "rpss": 0.208, "acc": 0.455 }, "ScTr": { "fc_pct": 12.3, "clim_pct": 16.1, "rpss": 0.454, "acc": 0.787 }, "ScBL": { "fc_pct": 14.9, "clim_pct": 18.6, "rpss": 0.261, "acc": 0.601 }, "AR": { "fc_pct": 8.9, "clim_pct": 10.7, "rpss": 0.194, "acc": 0.406 }, "GL": { "fc_pct": 2.1, "clim_pct": 11.8, "rpss": 0.214, "acc": 0.353 } } }, { "month": "2026-11", "part_elapsed": false, "regimes": { "AT": { "fc_pct": 16.0, "clim_pct": 14.6, "rpss": 0.142, "acc": 0.301 }, "EuBL": { "fc_pct": 7.2, "clim_pct": 13.7, "rpss": -0.067, "acc": -0.333 }, "ZO": { "fc_pct": 15.2, "clim_pct": 16.5, "rpss": 0.025, "acc": -0.209 }, "ScTr": { "fc_pct": 9.9, "clim_pct": 14.3, "rpss": 0.045, "acc": -0.114 }, "ScBL": { "fc_pct": 17.8, "clim_pct": 13.9, "rpss": -0.072, "acc": -0.184 }, "AR": { "fc_pct": 14.5, "clim_pct": 13.3, "rpss": 0.18, "acc": 0.33 }, "GL": { "fc_pct": 19.4, "clim_pct": 13.6, "rpss": 0.039, "acc": -0.162 } } }, { "month": "2026-12", "part_elapsed": false, "regimes": { "AT": { "fc_pct": 17.0, "clim_pct": 15.7, "rpss": 0.067, "acc": -0.122 }, "EuBL": { "fc_pct": 8.0, "clim_pct": 13.0, "rpss": -0.005, "acc": 0.352 }, "ZO": { "fc_pct": 17.7, "clim_pct": 17.9, "rpss": 0.084, "acc": 0.072 }, "ScTr": { "fc_pct": 11.3, "clim_pct": 14.1, "rpss": 0.012, "acc": -0.297 }, "ScBL": { "fc_pct": 13.7, "clim_pct": 13.0, "rpss": -0.171, "acc": -0.214 }, "AR": { "fc_pct": 18.5, "clim_pct": 12.4, "rpss": -0.023, "acc": -0.241 }, "GL": { "fc_pct": 13.8, "clim_pct": 14.0, "rpss": 0.004, "acc": -0.072 } } }, { "month": "2027-01", "part_elapsed": false, "regimes": { "AT": { "fc_pct": 14.7, "clim_pct": 15.9, "rpss": 0.146, "acc": 0.478 }, "EuBL": { "fc_pct": 10.7, "clim_pct": 13.3, "rpss": 0.023, "acc": 0.095 }, "ZO": { "fc_pct": 8.9, "clim_pct": 19.5, "rpss": 0.064, "acc": 0.23 }, "ScTr": { "fc_pct": 12.0, "clim_pct": 12.0, "rpss": 0.154, "acc": 0.1 }, "ScBL": { "fc_pct": 13.6, "clim_pct": 11.2, "rpss": 0.009, "acc": -0.007 }, "AR": { "fc_pct": 16.6, "clim_pct": 12.8, "rpss": -0.06, "acc": -0.002 }, "GL": { "fc_pct": 23.5, "clim_pct": 15.3, "rpss": 0.063, "acc": -0.012 } } }, { "month": "2027-02", "part_elapsed": false, "regimes": { "AT": { "fc_pct": 12.0, "clim_pct": 15.5, "rpss": 0.103, "acc": 0.504 }, "EuBL": { "fc_pct": 9.9, "clim_pct": 13.5, "rpss": 0.044, "acc": -0.116 }, "ZO": { "fc_pct": 7.3, "clim_pct": 19.7, "rpss": 0.008, "acc": -0.071 }, "ScTr": { "fc_pct": 13.7, "clim_pct": 11.0, "rpss": 0.046, "acc": 0.03 }, "ScBL": { "fc_pct": 7.6, "clim_pct": 10.9, "rpss": 0.038, "acc": -0.337 }, "AR": { "fc_pct": 18.6, "clim_pct": 12.5, "rpss": 0.129, "acc": 0.061 }, "GL": { "fc_pct": 30.9, "clim_pct": 16.9, "rpss": 0.18, "acc": 0.251 } } }, { "month": "2027-03", "part_elapsed": false, "regimes": { "AT": { "fc_pct": 14.3, "clim_pct": 17.1, "rpss": -0.203, "acc": -0.522 }, "EuBL": { "fc_pct": 7.2, "clim_pct": 13.4, "rpss": -0.092, "acc": -0.277 }, "ZO": { "fc_pct": 11.9, "clim_pct": 17.3, "rpss": 0.164, "acc": 0.381 }, "ScTr": { "fc_pct": 11.7, "clim_pct": 11.9, "rpss": 0.209, "acc": 0.626 }, "ScBL": { "fc_pct": 14.2, "clim_pct": 11.5, "rpss": 0.097, "acc": 0.056 }, "AR": { "fc_pct": 20.9, "clim_pct": 13.9, "rpss": 0.055, "acc": 0.133 }, "GL": { "fc_pct": 19.8, "clim_pct": 14.9, "rpss": 0.209, "acc": 0.339 } } }, { "month": "2027-04", "part_elapsed": false, "regimes": { "AT": { "fc_pct": 18.3, "clim_pct": 17.6, "rpss": 0.025, "acc": 0.354 }, "EuBL": { "fc_pct": 14.6, "clim_pct": 14.3, "rpss": -0.058, "acc": -0.071 }, "ZO": { "fc_pct": 13.7, "clim_pct": 15.8, "rpss": 0.044, "acc": 0.009 }, "ScTr": { "fc_pct": 9.8, "clim_pct": 12.2, "rpss": 0.016, "acc": -0.07 }, "ScBL": { "fc_pct": 16.6, "clim_pct": 11.8, "rpss": 0.029, 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apart; the wind must return westerly for 10 consecutive days before 30 Apr or the event is the vortex's annual final warming, not a sudden one", "skill": { "08": { "month": "08", "winters": 24, "window": [ "08-02", "03-04" ], "obs_rate": 0.4583333333333333, "model_rate": 0.685, "brier": 0.3112, "bss": -0.15122237762237734, "roc": 0.4755244755244755, "obs_rate_confirmed": 0.2916666666666667, "model_rate_confirmed": 0.49333333333333335, "brier_confirmed": 0.24833333333333338, "bss_confirmed": -0.10393557422969235, "roc_confirmed": 0.5126050420168067, "n_provisional": 5, "acc_u_djf": 0.19967242487459277, "bias_u_djf": -3.3063457519528163, "rows": [ { "winter": 1993, "p_model": 0.72, "obs": 0, "p_model_confirmed": 0.52, "obs_confirmed": 0, "n_obs": 0, "n_obs_provisional": 0, "model_mean_count": 0.8, "u_djf_model": 23.200744903419373, "u_djf_era5": 28.38678888888889 }, { "winter": 1994, "p_model": 0.68, "obs": 0, "p_model_confirmed": 0.36, "obs_confirmed": 0, "n_obs": 0, 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It is included above with part_elapsed=1 and is excluded from every headline on this site.", "A tercile probability near 33.3 is a model saying nothing. Most of these are nearer 33 than not, and that is the honest state of monthly seasonal forecasting rather than a fault in the run.", "Seasonal rainfall is far weaker than seasonal temperature everywhere, and over much of the world a rainfall tercile is not worth issuing at all. The beats_clim_pct column is what says where.", "Skill decays fast with lead. Over the United States, temperature beat climatology over 54-61 percent of the box at November 2026 and 46-89 percent by March 2027. Treat the far leads as context, not guidance.", "The systems do not share a reforecast period - SEAS5 1993-2016; C3S multi-system 1993-2016; NMME 1991-2016 - so their tercile boundaries come from slightly different climates. Comparisons within one system are exact; comparisons across them are close but not matched.", "Two forecasts on this site disagree, and comparing their published headline numbers gives the wrong answer: put on identical footing at /assets/compare/compare.json the ranking reverses. Do not rank systems by numbers taken from different routes without checking the footing first.", "Do not rank the vortex initialisation months by roc or bss. A later init_month runs a longer window into spring, where a wind reversal can be the vortex's final warming rather than a sudden one and the window is too short to apply the 30 April recovery test. That raises obs_rate and flatters a model that forecasts a warming almost every year. Init month 09 scores above 0.55 on roc and below it on roc_conf - the gain is the window, not the forecast. Score on the _conf columns." ], "endpoints": [ { "path": "/assets/feed.json", "route": "08", "holds": "This feed: headline, broadcast lines, the regional outlook, and this index" }, { "path": "/wire.txt", "route": "08", "holds": "The whole outlook as plain text, section-marked and pipe-delimited" }, { "path": "/assets/seas5/latest.json", "route": "01", "holds": "Route 01 pointer: newest initialisation and every cycle published" }, { "path": "/assets/seas5//catalog.json", "route": "01", "holds": "Route 01 catalog: 16 fields, 7 leads, 5 seasons, the 51-member layers, and the colour LUT every raster is encoded with" }, { "path": "/assets/probs/probs.json", "route": "10", "holds": "Route 10: SEAS5 tercile probabilities, raw and trend-adjusted, with RPSS and ACC by lead" }, { "path": "/assets/multi/multi.json", "route": "03", "holds": "Route 03: ten C3S systems, the consensus, and each system's own reforecast score" }, { "path": "/assets/nmme/nmme.json", "route": "02", "holds": "Route 02: four NMME models, the consensus, and each model's own reforecast score" }, { "path": "/assets/analog/analog.json", "route": "09", "holds": "Route 09: this site's own analog forecast, its analog years and its cross-validated skill" }, { "path": "/assets/compare/compare.json", "route": "11", "holds": "Route 11: the matched verification of routes 09 and 10 over the same years" }, { "path": "/assets/cities/cities.json", "route": "07", "holds": "Route 07: 40 city briefings, each with the skill of its own gridcell attached" }, { "path": "/assets/regimes/regimes.json", "route": "12", "holds": "Route 12: the seven Euro-Atlantic weather regimes, SEAS5's monthly frequencies against its own climatology, with ACC and RPSS" }, { "path": "/assets/vortex/vortex_skill.json", "route": "13", "holds": "Route 13: Brier skill, ROC area and DJF-U60 anomaly correlation for the stratospheric vortex, per initialisation month over 24 reforecast winters" }, { "path": "/assets/dailyfc/latest.json", "route": "16", "holds": "Route 16 pointer: newest daily MEMBER initialisation. 51 members on a daily axis - percentiles, spread and absolute-threshold chances; no reforecast behind it, so no anomalies, no terciles and no skill score" }, { "path": "/assets/dailyfc//catalog.json", "route": "16", "holds": "Route 16 catalog: 8 fields x 215 daily frames x (mean, percentiles, spread, chance layers), each with its own legend, units and colour LUT, plus the per-place plume index" }, { "path": "/assets/sfs/sfs.json", "route": "15", "holds": "Route 15: NOAA SFS Beta, TWELVE monthly leads from 31 members against a 1991-2025 reforecast - tercile probabilities raw and trend-adjusted, RPSS and ACC at every lead, the same on each WHOLE three-month season the start covers (DJF/MAM/JJA/SON, in skill_season and terciles_season), UNSCORED snowfall probabilities in `snow` and `snow_season` (ERA5 here has no snowfall, so they carry no RPSS and no ACC), and the Nino-3.4 plume from the model's own ocean (experiment beta1)" }, { "path": "/assets/nino/nino.json", "route": "03", "holds": "Route 03 ENSO: Nino 3.4, 3, 4, 1+2, relative Nino 3.4 and the IOD from the ten Copernicus systems - every member, each system's mean and ACC/RMSE vs ERA5, the one-vote consensus, and the strongest months in the ERA5 record" }, { "path": "/assets/sfs/enso.json", "route": "15", "holds": "Route 15: Nino 3.4, 3, 4, 1+2, relative Nino 3.4 and the IOD from the SFS ocean - beta1 and beta2, 31 members x 12 leads, each lead's ACC/RMSE vs ERA5 beside persistence and the ensemble's spread" }, { "path": "/assets/sfs/beta2/sfs.json", "route": "15", "holds": "Route 15: the same document for SFS experiment beta2, a different model on the same 31x12 live and 11x35 reforecast design; published only for starts whose calendar month beta2 has a reforecast for" } ] }