A retrospective test on public data: the system forecast 90 days ahead from 13 past dates, and the forecasts were scored against what actually happened. It is not a live track record. The live track record (below) is separate and only counts days after each forecast was issued.
183 series: 63 Wikipedia articles from a fixed list, and 20 cities x 6 weather variables. Forecast start dates every 14 days; 3 early dates (Oct-Dec 2025) were used only to pick each series' simple reference method, and the 10 later dates (25 Mar to 29 Jul 2026) were scored. Numbers below are ratios of average absolute error: below 1.00 means the system's error was lower than the reference, above 1.00 means higher. Each series counts equally (geometric mean across series). Each forecast used only data up to its start date.
Versus each series’ best simple reference (picked on the early dates)
The reference is one of seven simple methods (repeat last value, same weekday, same day last year, recent average or median, climatology). Not a fixed method, so read the other two tables as well.
| Group | Series | 1-7 days | 8-30 days | 31-90 days |
|---|
| Wikipedia pageviews | 63 | 0.54 (98% wins) | 0.60 (95% wins) | 0.57 (98% wins) |
| Temperature | 20 | 0.81 (90% wins) | 0.93 (65% wins) | 0.93 (75% wins) |
| Humidity | 20 | 0.81 (95% wins) | 0.90 (75% wins) | 0.88 (100% wins) |
| Air pressure | 20 | 0.83 (90% wins) | 0.88 (90% wins) | 0.89 (80% wins) |
| Solar radiation | 20 | 0.92 (80% wins) | 0.91 (90% wins) | 0.89 (90% wins) |
| Max wind | 20 | 0.95 (85% wins) | 0.94 (85% wins) | 0.94 (70% wins) |
| Rain | 20 | 0.93 (70% wins) | 0.91 (80% wins) | 0.89 (75% wins) |
Versus repeating the last value
A weak reference at long range, so these ratios flatter the system.
| Group | Series | 1-7 days | 8-30 days | 31-90 days |
|---|
| Wikipedia pageviews | 63 | 0.73 (86% wins) | 0.69 (92% wins) | 0.58 (94% wins) |
| Temperature | 20 | 0.80 (85% wins) | 0.62 (100% wins) | 0.36 (100% wins) |
| Humidity | 20 | 0.82 (90% wins) | 0.74 (100% wins) | 0.61 (100% wins) |
| Air pressure | 20 | 0.80 (90% wins) | 0.67 (100% wins) | 0.62 (100% wins) |
| Solar radiation | 20 | 0.82 (90% wins) | 0.68 (100% wins) | 0.44 (100% wins) |
| Max wind | 20 | 0.81 (95% wins) | 0.75 (100% wins) | 0.75 (100% wins) |
| Rain | 20 | 0.73 (95% wins) | 0.65 (100% wins) | 0.63 (100% wins) |
Versus a seasonal reference
Wikipedia: repeating the same weekday last week. Weather: the typical value for that date in the previous four years (climatology).
| Group | Series | 1-7 days | 8-30 days | 31-90 days |
|---|
| Wikipedia pageviews | 63 | 0.61 (95% wins) | 0.66 (95% wins) | 0.55 (95% wins) |
| Temperature | 20 | 0.83 (90% wins) | 0.95 (65% wins) | 0.95 (75% wins) |
| Humidity | 20 | 0.85 (90% wins) | 0.96 (55% wins) | 0.96 (80% wins) |
| Air pressure | 20 | 0.86 (90% wins) | 0.96 (80% wins) | 0.96 (80% wins) |
| Solar radiation | 20 | 0.93 (80% wins) | 0.95 (90% wins) | 0.94 (90% wins) |
| Max wind | 20 | 0.82 (95% wins) | 0.82 (95% wins) | 0.82 (90% wins) |
| Rain | 20 | 0.97 (70% wins) | 0.98 (75% wins) | 0.99 (55% wins) |
Where it lost, and a few clear wins (31-90 day window)
Ratio versus the selected reference. Worst 8 of 183 series, and the 5 best excluding event articles (Easter, Christmas and similar had no event inside the test window, so their very low ratios say nothing about event skill and are left out).
| Worst | Ratio |
|---|
| Temperature: Beirut | 1.26 |
| Wikipedia pageviews: Diwali | 1.21 |
| Max wind: Sydney | 1.13 |
| Max wind: Istanbul | 1.08 |
| Temperature: Istanbul | 1.08 |
| Temperature: BuenosAires | 1.07 |
| Solar radiation: Sydney | 1.07 |
| Max wind: Beirut | 1.07 |
| Best (non-event) | Ratio |
|---|
| Wikipedia pageviews: Lebanon | 0.31 |
| Wikipedia pageviews: Nobel Prize | 0.31 |
| Wikipedia pageviews: Beirut | 0.37 |
| Solar radiation: Johannesburg | 0.39 |
| Wikipedia pageviews: Photosynthesis | 0.40 |
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