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

All stations (mean of daily station errors) · ECMWF IFS HRES · lead day 9

ALL · ifs_hres · lead 9

Target day = initialization date + 9 days. 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, ifs-gpid161, starting 2026-08-01 — 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
tmax00Zbilinear30d16 2 QC4.25 [3.63, 4.98]1.66-1.41 [-2.80, -0.49]5.60 [4.68, 6.39]15% [8%, 21%]30%45%+0.05-0.462026-08-10 → 2026-08-30
tmax00Zbilinear90d16 2 QC4.25 [3.58, 5.00]1.66-1.41 [-3.58, -0.40]5.60 [4.64, 6.43]15% [2%, 23%]30%45%+0.05-0.462026-08-10 → 2026-08-30
tmax00Zbilinear365d16 2 QC4.25 [3.59, 5.06]1.66-1.41 [-3.32, -0.33]5.60 [4.70, 6.50]15% [4%, 23%]30%45%+0.05-0.462026-08-10 → 2026-08-30
tmax00Zbilinearall16 2 QC4.25 [3.56, 5.03]1.66-1.41 [-3.20, -0.30]5.60 [4.69, 6.40]15% [4%, 24%]30%45%+0.05-0.462026-08-10 → 2026-08-30
tmax00Znearest30d16 2 QC4.28 [3.59, 5.03]1.67-1.27 [-2.66, -0.34]5.66 [4.63, 6.52]15% [10%, 20%]31%47%+0.04-0.482026-08-10 → 2026-08-30
tmax00Znearest90d16 2 QC4.28 [3.55, 5.04]1.67-1.27 [-3.45, -0.26]5.66 [4.59, 6.55]15% [6%, 21%]31%47%+0.04-0.482026-08-10 → 2026-08-30
tmax00Znearest365d16 2 QC4.28 [3.56, 5.10]1.67-1.27 [-3.19, -0.19]5.66 [4.65, 6.60]15% [6%, 21%]31%47%+0.04-0.482026-08-10 → 2026-08-30
tmax00Znearestall16 2 QC4.28 [3.52, 5.06]1.67-1.27 [-3.08, -0.14]5.66 [4.63, 6.53]15% [6%, 22%]31%47%+0.04-0.482026-08-10 → 2026-08-30
tmax12Zbilinear30d15 2 QC4.82 [4.23, 5.19]1.72-3.57 [-4.25, -2.54]6.02 [5.29, 6.46]14% [12%, 16%]24%36%-0.08-0.452026-08-10 → 2026-08-30
tmax12Zbilinear90d15 2 QC4.82 [3.78, 5.19]1.72-3.57 [-4.27, -2.41]6.02 [4.62, 6.44]14% [12%, 16%]24%36%-0.08-0.452026-08-10 → 2026-08-30
tmax12Zbilinear365d15 2 QC4.82 [3.79, 5.20]1.72-3.57 [-4.32, -2.43]6.02 [4.66, 6.49]14% [12%, 16%]24%36%-0.08-0.452026-08-10 → 2026-08-30
tmax12Zbilinearall15 2 QC4.82 [3.79, 5.19]1.72-3.57 [-4.33, -2.40]6.02 [4.65, 6.46]14% [11%, 16%]24%36%-0.08-0.452026-08-10 → 2026-08-30
tmax12Znearest30d15 2 QC4.84 [4.09, 5.25]1.77-3.59 [-4.31, -2.51]6.14 [5.23, 6.60]16% [14%, 21%]28%37%-0.08-0.492026-08-10 → 2026-08-30
tmax12Znearest90d15 2 QC4.84 [3.31, 5.26]1.77-3.59 [-4.32, -2.28]6.14 [4.34, 6.62]16% [14%, 25%]28%37%-0.08-0.492026-08-10 → 2026-08-30
tmax12Znearest365d15 2 QC4.84 [3.40, 5.27]1.77-3.59 [-4.35, -2.28]6.14 [4.44, 6.65]16% [14%, 24%]28%37%-0.08-0.492026-08-10 → 2026-08-30
tmax12Znearestall15 2 QC4.84 [3.40, 5.27]1.77-3.59 [-4.36, -2.28]6.14 [4.44, 6.63]16% [14%, 24%]28%37%-0.08-0.492026-08-10 → 2026-08-30
tmin00Zbilinear30d16 2 QC4.24 [3.75, 4.62]1.31+2.93 [1.91, 3.50]5.45 [4.83, 5.92]16% [13%, 19%]34%46%-0.14-0.442026-08-10 → 2026-08-30
tmin00Zbilinear90d16 2 QC4.24 [3.44, 4.61]1.31+2.93 [1.53, 3.49]5.45 [4.49, 5.92]16% [12%, 19%]34%46%-0.14-0.442026-08-10 → 2026-08-30
tmin00Zbilinear365d16 2 QC4.24 [3.50, 4.62]1.31+2.93 [1.61, 3.51]5.45 [4.66, 5.94]16% [11%, 19%]34%46%-0.14-0.442026-08-10 → 2026-08-30
tmin00Zbilinearall16 2 QC4.24 [3.51, 4.64]1.31+2.93 [1.61, 3.61]5.45 [4.62, 5.95]16% [11%, 19%]34%46%-0.14-0.442026-08-10 → 2026-08-30
tmin00Znearest30d16 2 QC4.40 [3.91, 4.78]1.33+3.04 [1.99, 3.62]5.64 [5.04, 6.11]16% [12%, 21%]31%43%-0.18-0.462026-08-10 → 2026-08-30
tmin00Znearest90d16 2 QC4.40 [3.58, 4.77]1.33+3.04 [1.65, 3.62]5.64 [4.64, 6.11]16% [11%, 24%]31%43%-0.18-0.462026-08-10 → 2026-08-30
tmin00Znearest365d16 2 QC4.40 [3.70, 4.78]1.33+3.04 [1.72, 3.64]5.64 [4.89, 6.14]16% [11%, 23%]31%43%-0.18-0.462026-08-10 → 2026-08-30
tmin00Znearestall16 2 QC4.40 [3.68, 4.79]1.33+3.04 [1.72, 3.76]5.64 [4.86, 6.14]16% [11%, 23%]31%43%-0.18-0.462026-08-10 → 2026-08-30
tmin12Zbilinear30d15 2 QC3.38 [3.00, 3.65]1.07+1.16 [0.77, 1.74]4.23 [3.76, 4.52]16% [13%, 19%]37%53%+0.08-0.152026-08-10 → 2026-08-30
tmin12Zbilinear90d15 2 QC3.38 [2.96, 3.66]1.07+1.16 [0.75, 2.06]4.23 [3.69, 4.53]16% [13%, 19%]37%53%+0.08-0.152026-08-10 → 2026-08-30
tmin12Zbilinear365d15 2 QC3.38 [2.85, 3.67]1.07+1.16 [0.75, 2.00]4.23 [3.56, 4.54]16% [13%, 20%]37%53%+0.08-0.152026-08-10 → 2026-08-30
tmin12Zbilinearall15 2 QC3.38 [2.85, 3.70]1.07+1.16 [0.74, 2.00]4.23 [3.58, 4.56]16% [13%, 20%]37%53%+0.08-0.152026-08-10 → 2026-08-30
tmin12Znearest30d15 2 QC3.52 [3.11, 3.80]1.10+1.18 [0.77, 1.79]4.47 [3.93, 4.77]19% [15%, 24%]35%50%+0.04-0.192026-08-10 → 2026-08-30
tmin12Znearest90d15 2 QC3.52 [3.08, 3.80]1.10+1.18 [0.73, 2.13]4.47 [3.87, 4.77]19% [15%, 24%]35%50%+0.04-0.192026-08-10 → 2026-08-30
tmin12Znearest365d15 2 QC3.52 [3.00, 3.83]1.10+1.18 [0.73, 2.04]4.47 [3.78, 4.78]19% [15%, 24%]35%50%+0.04-0.192026-08-10 → 2026-08-30
tmin12Znearestall15 2 QC3.52 [2.99, 3.85]1.10+1.18 [0.73, 2.07]4.47 [3.78, 4.82]19% [14%, 24%]35%50%+0.04-0.192026-08-10 → 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 ECMWF IFS HRES at ALL, lead day 9, 00Z bilinear tmax+5+2.50-2.5-52026-08-10: -3.92 °F2026-08-16: +0.56 °F2026-08-17: -4.03 °F2026-08-18: -2.71 °F2026-08-19: -2.02 °F2026-08-20: +0.4 °F2026-08-21: +4.8 °F2026-08-22: -0.27 °F2026-08-23: -1.63 °F2026-08-24: -0.16 °F2026-08-25: -2.34 °F2026-08-26: -0.7 °F2026-08-27: -1.76 °F2026-08-28: -3.75 °F2026-08-29: -3.78 °F2026-08-30: -1.23 °F2026-08-102026-08-30°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 (21 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-1.23
2026-08-29-3.78
2026-08-28-3.75
2026-08-27-1.76
2026-08-26-0.70
2026-08-25-2.34
2026-08-24-0.16
2026-08-23-1.63
2026-08-22-0.27
2026-08-21+4.80
2026-08-20+0.40
2026-08-19-2.02
2026-08-18-2.71
2026-08-17-4.03
2026-08-16+0.56
2026-08-15—
2026-08-14—
2026-08-13—
2026-08-12—
2026-08-11—
2026-08-10-3.92

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at ALL, lead day 9-5 to -4.5 °F: 0 days-4.5 to -4 °F: 1 day-4 to -3.5 °F: 3 days-3.5 to -3 °F: 0 days-3 to -2.5 °F: 1 day-2.5 to -2 °F: 2 days-2 to -1.5 °F: 2 days-1.5 to -1 °F: 1 day-1 to -0.5 °F: 1 day-0.5 to 0 °F: 2 days0 to 0.5 °F: 1 day0.5 to 1 °F: 1 day1 to 1.5 °F: 0 days1.5 to 2 °F: 0 days2 to 2.5 °F: 0 days2.5 to 3 °F: 0 days3 to 3.5 °F: 0 days3.5 to 4 °F: 0 days4 to 4.5 °F: 0 days4.5 to 5 °F: 1 daydashed: P50 |e| 1.89 · P90 |e| 3.98 °F-50+5 °Fn = 16 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
-5.00-4.500
-4.50-4.001
-4.00-3.503
-3.50-3.000
-3.00-2.501
-2.50-2.002
-2.00-1.502
-1.50-1.001
-1.00-0.501
-0.50+0.002
+0.00+0.501
+0.50+1.001
+1.00+1.500
+1.50+2.000
+2.00+2.500
+2.50+3.000
+3.00+3.500
+3.50+4.000
+4.00+4.500
+4.50+5.001

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08162.13 -1.41

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-10 → 2026-08-30 16
ECMWF IFS HRES2026-08-10 → 2026-08-30 16
ECMWF IFS HRES2026-08-10 → 2026-08-30 15
ECMWF IFS HRES2026-08-10 → 2026-08-30 15

Compared with other models

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

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 16 -0.60 [-1.19, 0.60] no
NCEP GFS 16 -0.37 [-1.28, 0.78] no
GraphCast (IFS init) 16 -1.88 [-2.79, 0.03] no
Persistence (baseline) 16 -0.21 [-0.72, 0.90] no

Cite this page

ShortCastCheck, ALL ifs_hres lead 9, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/ALL/model/ifs_hres/lead/9/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: ALL (All stations (mean of daily station errors)), model ifs_hres, lead day 9. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/ALL/model/ifs_hres/lead/9/

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