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CastCheck methodology v0.2 · data through 2026-08-30

All stations (mean of daily station errors) · Aurora (IFS init) · lead day 1

ALL · aurora_ifs · lead 1

Target day = initialization date + 1 day. This page is a permanent link: the numbers change as history accumulates, the address and the methodology version do not.

Scores use the latest model version segment, AURO_v100, starting 2026-08-28 — days before that ran a different version of the model and are excluded rather than silently pooled. Of the scored days, 2 carry a QC flag on the observation.

JSON for this page CSV of the daily errors Cite this page

Every number for this combination

All four windows × both initializations × both interpolations × both variables. Errors are computed in °C and shown in °F; CI is a 95 % moving-block bootstrap interval. MAE debiased and skill, debiased remove the constant offset of the window first, so a station that the model always reads a degree too warm is not scored as if it had no skill — compare the two skill columns to see how much of the error is a fixed offset. n QC next to n counts days whose observation carries a QC flag.

VariableInitMethod Windown MAE °F MAE debiased Bias °F RMSE °F ±1 °F±2 °F±3 °F Skill Skill, debiased Period
tmax00Zbilinear30d2 2 QC5.28 [5.07, 5.48]0.21-5.27 [-5.48, -5.06]5.80 [5.63, 5.97]9% [9%, 9%]13%22%-0.71+0.682026-08-29 → 2026-08-30
tmax00Zbilinear90d2 2 QC5.28 [5.07, 5.48]0.21-5.27 [-5.48, -5.06]5.80 [5.63, 5.97]9% [9%, 9%]13%22%-0.71+0.682026-08-29 → 2026-08-30
tmax00Zbilinear365d2 2 QC5.28 [5.07, 5.48]0.21-5.27 [-5.48, -5.06]5.80 [5.63, 5.97]9% [9%, 9%]13%22%-0.71+0.682026-08-29 → 2026-08-30
tmax00Zbilinearall2 2 QC5.28 [5.07, 5.48]0.21-5.27 [-5.48, -5.06]5.80 [5.63, 5.97]9% [9%, 9%]13%22%-0.71+0.682026-08-29 → 2026-08-30
tmax00Znearest30d2 2 QC5.21 [4.92, 5.51]0.30-5.19 [-5.49, -4.88]5.79 [5.51, 6.05]9% [9%, 9%]15%24%-0.69+0.542026-08-29 → 2026-08-30
tmax00Znearest90d2 2 QC5.21 [4.92, 5.51]0.30-5.19 [-5.49, -4.88]5.79 [5.51, 6.05]9% [9%, 9%]15%24%-0.69+0.542026-08-29 → 2026-08-30
tmax00Znearest365d2 2 QC5.21 [4.92, 5.51]0.30-5.19 [-5.49, -4.88]5.79 [5.51, 6.05]9% [9%, 9%]15%24%-0.69+0.542026-08-29 → 2026-08-30
tmax00Znearestall2 2 QC5.21 [4.92, 5.51]0.30-5.19 [-5.49, -4.88]5.79 [5.51, 6.05]9% [9%, 9%]15%24%-0.69+0.542026-08-29 → 2026-08-30
tmax12Zbilinear30d2 2 QC5.62 [5.36, 5.88]0.26-5.62 [-5.88, -5.36]6.07 [5.91, 6.24]4% [0%, 9%]15%22%-0.82+0.612026-08-29 → 2026-08-30
tmax12Zbilinear90d2 2 QC5.62 [5.36, 5.88]0.26-5.62 [-5.88, -5.36]6.07 [5.91, 6.24]4% [0%, 9%]15%22%-0.82+0.612026-08-29 → 2026-08-30
tmax12Zbilinear365d2 2 QC5.62 [5.36, 5.88]0.26-5.62 [-5.88, -5.36]6.07 [5.91, 6.24]4% [0%, 9%]15%22%-0.82+0.612026-08-29 → 2026-08-30
tmax12Zbilinearall2 2 QC5.62 [5.36, 5.88]0.26-5.62 [-5.88, -5.36]6.07 [5.91, 6.24]4% [0%, 9%]15%22%-0.82+0.612026-08-29 → 2026-08-30
tmax12Znearest30d2 2 QC5.53 [5.19, 5.87]0.34-5.53 [-5.87, -5.19]6.05 [5.78, 6.30]4% [0%, 9%]15%22%-0.79+0.492026-08-29 → 2026-08-30
tmax12Znearest90d2 2 QC5.53 [5.19, 5.87]0.34-5.53 [-5.87, -5.19]6.05 [5.78, 6.30]4% [0%, 9%]15%22%-0.79+0.492026-08-29 → 2026-08-30
tmax12Znearest365d2 2 QC5.53 [5.19, 5.87]0.34-5.53 [-5.87, -5.19]6.05 [5.78, 6.30]4% [0%, 9%]15%22%-0.79+0.492026-08-29 → 2026-08-30
tmax12Znearestall2 2 QC5.53 [5.19, 5.87]0.34-5.53 [-5.87, -5.19]6.05 [5.78, 6.30]4% [0%, 9%]15%22%-0.79+0.492026-08-29 → 2026-08-30
tmin00Zbilinear30d2 2 QC2.24 [2.12, 2.36]0.96+0.24 [-0.71, 1.20]2.90 [2.88, 2.93]30% [30%, 30%]59%70%+0.13+0.402026-08-29 → 2026-08-30
tmin00Zbilinear90d2 2 QC2.24 [2.12, 2.36]0.96+0.24 [-0.71, 1.20]2.90 [2.88, 2.93]30% [30%, 30%]59%70%+0.13+0.402026-08-29 → 2026-08-30
tmin00Zbilinear365d2 2 QC2.24 [2.12, 2.36]0.96+0.24 [-0.71, 1.20]2.90 [2.88, 2.93]30% [30%, 30%]59%70%+0.13+0.402026-08-29 → 2026-08-30
tmin00Zbilinearall2 2 QC2.24 [2.12, 2.36]0.96+0.24 [-0.71, 1.20]2.90 [2.88, 2.93]30% [30%, 30%]59%70%+0.13+0.402026-08-29 → 2026-08-30
tmin00Znearest30d2 2 QC2.23 [2.15, 2.31]0.94+0.20 [-0.75, 1.14]3.01 [3.00, 3.02]37% [30%, 43%]63%70%+0.14+0.412026-08-29 → 2026-08-30
tmin00Znearest90d2 2 QC2.23 [2.15, 2.31]0.94+0.20 [-0.75, 1.14]3.01 [3.00, 3.02]37% [30%, 43%]63%70%+0.14+0.412026-08-29 → 2026-08-30
tmin00Znearest365d2 2 QC2.23 [2.15, 2.31]0.94+0.20 [-0.75, 1.14]3.01 [3.00, 3.02]37% [30%, 43%]63%70%+0.14+0.412026-08-29 → 2026-08-30
tmin00Znearestall2 2 QC2.23 [2.15, 2.31]0.94+0.20 [-0.75, 1.14]3.01 [3.00, 3.02]37% [30%, 43%]63%70%+0.14+0.412026-08-29 → 2026-08-30
tmin12Zbilinear30d2 2 QC2.23 [1.95, 2.51]0.92-0.11 [-1.03, 0.80]2.86 [2.70, 3.01]30% [13%, 48%]61%67%+0.14+0.432026-08-29 → 2026-08-30
tmin12Zbilinear90d2 2 QC2.23 [1.95, 2.51]0.92-0.11 [-1.03, 0.80]2.86 [2.70, 3.01]30% [13%, 48%]61%67%+0.14+0.432026-08-29 → 2026-08-30
tmin12Zbilinear365d2 2 QC2.23 [1.95, 2.51]0.92-0.11 [-1.03, 0.80]2.86 [2.70, 3.01]30% [13%, 48%]61%67%+0.14+0.432026-08-29 → 2026-08-30
tmin12Zbilinearall2 2 QC2.23 [1.95, 2.51]0.92-0.11 [-1.03, 0.80]2.86 [2.70, 3.01]30% [13%, 48%]61%67%+0.14+0.432026-08-29 → 2026-08-30
tmin12Znearest30d2 2 QC2.21 [1.91, 2.51]0.90-0.16 [-1.06, 0.74]2.95 [2.82, 3.08]39% [17%, 61%]59%67%+0.15+0.442026-08-29 → 2026-08-30
tmin12Znearest90d2 2 QC2.21 [1.91, 2.51]0.90-0.16 [-1.06, 0.74]2.95 [2.82, 3.08]39% [17%, 61%]59%67%+0.15+0.442026-08-29 → 2026-08-30
tmin12Znearest365d2 2 QC2.21 [1.91, 2.51]0.90-0.16 [-1.06, 0.74]2.95 [2.82, 3.08]39% [17%, 61%]59%67%+0.15+0.442026-08-29 → 2026-08-30
tmin12Znearestall2 2 QC2.21 [1.91, 2.51]0.90-0.16 [-1.06, 0.74]2.95 [2.82, 3.08]39% [17%, 61%]59%67%+0.15+0.442026-08-29 → 2026-08-30

+ model too warm · − model too cold · bias interval includes zero · ★ lowest MAE · = not distinguishable from the leader · ▼ significantly worse · n < 30 greyed and unranked · CI is a 95 % moving-block bootstrap interval.

Daily error, last 90 days

Daily forecast minus observed error in °F for Aurora (IFS init) at ALL, lead day 1, 00Z bilinear tmax+10+50-5-102026-08-29: -5.48 °F2026-08-30: -5.06 °F2026-08-292026-08-30°F, forecast − observed
Forecast − observed, °F, 00Z bilinear daily maximum. The dashed line is zero; the thick line is a centred 7-day mean, drawn only where the whole window is present. Gaps are days with no score, never interpolation. Hover a point for its date and value.
The same series as a table (2 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-5.06
2026-08-29-5.48

Error distribution

Distribution of the signed daily error in °F for Aurora (IFS init) at ALL, lead day 1-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 0 days-6 to -5 °F: 2 days-5 to -4 °F: 0 days-4 to -3 °F: 0 days-3 to -2 °F: 0 days-2 to -1 °F: 0 days-1 to 0 °F: 0 days0 to 1 °F: 0 days1 to 2 °F: 0 days2 to 3 °F: 0 days3 to 4 °F: 0 days4 to 5 °F: 0 days5 to 6 °F: 0 days6 to 7 °F: 0 days7 to 8 °F: 0 days8 to 9 °F: 0 days9 to 10 °F: 0 daysdashed: P50 |e| 5.27 · P90 |e| 5.44 °F-100+10 °Fn = 2 days
All scored days for 00Z bilinear daily maximum, 20 equal bins. The dashed marks are the 50th and 90th percentiles of the absolute error, mirrored on both sides. Hover a bar for its bin and count.
Bin counts as a table
From °FTo °FDays
-10.00-9.000
-9.00-8.000
-8.00-7.000
-7.00-6.000
-6.00-5.002
-5.00-4.000
-4.00-3.000
-3.00-2.000
-2.00-1.000
-1.00+0.000
+0.00+1.000
+1.00+2.000
+2.00+3.000
+3.00+4.000
+4.00+5.000
+5.00+6.000
+6.00+7.000
+7.00+8.000
+8.00+9.000
+9.00+10.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-0825.27 -5.27

Availability

ModelScored period DaysCoverage
Aurora (IFS init)2026-08-29 → 2026-08-30 2
Aurora (IFS init)2026-08-29 → 2026-08-30 2
Aurora (IFS init)2026-08-29 → 2026-08-30 2
Aurora (IFS init)2026-08-29 → 2026-08-30 2

Compared with other models

Paired bootstrap on the days both models cover (90d, 00Z, bilinear, daily maximum). Negative means Aurora (IFS init) has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 2 +1.80 [1.61, 1.99] yes
Aurora (GFS init) 1 -1.22 [-1.22, -1.22] yes
FourCastNet v2 (GFS init) 1 +1.17 [1.17, 1.17] yes
FourCastNet v2 (IFS init) 2 +1.28 [1.15, 1.40] yes
NCEP GFS 2 +2.22 [2.02, 2.42] yes
GraphCast (GFS init) 1 -0.88 [-0.88, -0.88] yes
GraphCast (IFS init) 2 -0.15 [-0.20, -0.10] yes
ECMWF IFS HRES 2 +1.61 [1.45, 1.77] yes
Pangu-Weather (GFS init) 1 +1.56 [1.56, 1.56] yes
Pangu-Weather (IFS init) 2 +1.19 [1.06, 1.33] yes
Persistence (baseline) 2 +2.19 [1.90, 2.48] yes

Cite this page

ShortCastCheck, ALL aurora_ifs lead 1, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/ALL/model/aurora_ifs/lead/1/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: ALL (All stations (mean of daily station errors)), model aurora_ifs, lead day 1. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/ALL/model/aurora_ifs/lead/1/

Accessed2026-08-31 (data through 2026-08-30; page built 2026-08-31T03:52:06+00:00)

JSON CSV all scores methodology v0.2 licence