Archive · one page per completed month
Monthly reviews
A month gets a page once it is over. Each page ranks the models on that month's days alone, states how complete the month's observations were, counts the quality-control flags raised, names the largest single-day error, and lists any upstream model version that first appeared in it. Every sentence on those pages is generated from the tables; none of them is a judgement.
Every completed monthnewest first
The month currently in progress has no page: a partial month would rank models on a handful of days and then change its own numbers for four weeks. A month appears here on the first build after its last day.
| Month | Days | Lowest MAE, among the models scored that month | MAE °F | Systems | Observations | QC flags | Version changes |
|---|---|---|---|---|---|---|---|
| September 2026 2026-09 | 30 | ECMWF AIFS Single | 2.24 | 11 | 100.0% | 741 | 0 |
| August 2026 2026-08 | 31 | ECMWF AIFS Single | 2.42 | 11 | 100.0% | 84 | 3 |
| July 2026 2026-07 | 31 | GraphCast (IFS init) | 2.58 | 8 | 100.0% | 11 | 0 |
| June 2026 2026-06 | 30 | GraphCast (IFS init) | 2.58 | 8 | 100.0% | 13 | 0 |
| May 2026 2026-05 | 31 | GraphCast (IFS init) | 2.57 | 8 | 100.0% | 27 | 0 |
| April 2026 2026-04 | 30 | GraphCast (IFS init) | 2.67 | 8 | 100.0% | 7 | 7 |
| March 2026 2026-03 | 31 | GraphCast (IFS init) | 2.92 | 8 | 100.0% | 10 | 1 |
| February 2026 2026-02 | 28 | Aurora (IFS init) | 2.81 | 8 | 100.0% | 14 | 0 |
| January 2026 2026-01 | 31 | Aurora (IFS init) | 2.54 | 8 | 100.0% | 5 | 8 |