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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 1

ALL · ifs_hres · 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, 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
tmax00Zbilinear30d23 2 QC3.56 [3.39, 3.74]0.65-2.83 [-3.25, -2.38]4.23 [4.05, 4.42]12% [11%, 14%]28%46%-0.33+0.062026-08-02 → 2026-08-30
tmax00Zbilinear90d23 2 QC3.56 [3.37, 3.78]0.65-2.83 [-3.34, -2.34]4.23 [4.05, 4.45]12% [10%, 15%]28%46%-0.33+0.062026-08-02 → 2026-08-30
tmax00Zbilinear365d23 2 QC3.56 [3.39, 3.80]0.65-2.83 [-3.39, -2.32]4.23 [4.05, 4.44]12% [10%, 14%]28%46%-0.33+0.062026-08-02 → 2026-08-30
tmax00Zbilinearall23 2 QC3.56 [3.37, 3.78]0.65-2.83 [-3.33, -2.33]4.23 [4.02, 4.44]12% [10%, 15%]28%46%-0.33+0.062026-08-02 → 2026-08-30
tmax00Znearest30d23 2 QC3.64 [3.40, 3.93]0.71-2.80 [-3.30, -2.25]4.43 [4.08, 4.77]15% [13%, 17%]29%46%-0.36-0.022026-08-02 → 2026-08-30
tmax00Znearest90d23 2 QC3.64 [3.32, 4.01]0.71-2.80 [-3.42, -2.15]4.43 [3.94, 4.82]15% [13%, 17%]29%46%-0.36-0.022026-08-02 → 2026-08-30
tmax00Znearest365d23 2 QC3.64 [3.33, 4.05]0.71-2.80 [-3.49, -2.15]4.43 [3.96, 4.86]15% [13%, 17%]29%46%-0.36-0.022026-08-02 → 2026-08-30
tmax00Znearestall23 2 QC3.64 [3.31, 3.98]0.71-2.80 [-3.40, -2.12]4.43 [3.93, 4.80]15% [13%, 17%]29%46%-0.36-0.022026-08-02 → 2026-08-30
tmax12Zbilinear30d24 2 QC3.65 [3.49, 3.82]0.49-3.22 [-3.45, -2.98]4.31 [4.15, 4.49]11% [9%, 14%]26%44%-0.37+0.262026-08-02 → 2026-08-30
tmax12Zbilinear90d24 2 QC3.65 [3.48, 3.85]0.49-3.22 [-3.48, -2.95]4.31 [4.12, 4.53]11% [9%, 15%]26%44%-0.37+0.262026-08-02 → 2026-08-30
tmax12Zbilinear365d24 2 QC3.65 [3.47, 3.85]0.49-3.22 [-3.50, -2.95]4.31 [4.12, 4.51]11% [9%, 14%]26%44%-0.37+0.262026-08-02 → 2026-08-30
tmax12Zbilinearall24 2 QC3.65 [3.47, 3.85]0.49-3.22 [-3.47, -2.95]4.31 [4.13, 4.52]11% [9%, 15%]26%44%-0.37+0.262026-08-02 → 2026-08-30
tmax12Znearest30d24 2 QC3.76 [3.60, 3.96]0.53-3.16 [-3.47, -2.80]4.54 [4.32, 4.78]12% [10%, 14%]27%44%-0.41+0.212026-08-02 → 2026-08-30
tmax12Znearest90d24 2 QC3.76 [3.58, 4.02]0.53-3.16 [-3.53, -2.74]4.54 [4.28, 4.82]12% [10%, 14%]27%44%-0.41+0.212026-08-02 → 2026-08-30
tmax12Znearest365d24 2 QC3.76 [3.57, 4.04]0.53-3.16 [-3.54, -2.74]4.54 [4.27, 4.83]12% [10%, 14%]27%44%-0.41+0.212026-08-02 → 2026-08-30
tmax12Znearestall24 2 QC3.76 [3.58, 4.00]0.53-3.16 [-3.53, -2.73]4.54 [4.27, 4.81]12% [10%, 14%]27%44%-0.41+0.212026-08-02 → 2026-08-30
tmin00Zbilinear30d23 2 QC2.33 [2.17, 2.51]0.53+1.16 [0.82, 1.46]3.03 [2.84, 3.23]30% [27%, 34%]55%71%+0.00+0.292026-08-02 → 2026-08-30
tmin00Zbilinear90d23 2 QC2.33 [2.17, 2.53]0.53+1.16 [0.77, 1.49]3.03 [2.83, 3.26]30% [26%, 34%]55%71%+0.00+0.292026-08-02 → 2026-08-30
tmin00Zbilinear365d23 2 QC2.33 [2.15, 2.53]0.53+1.16 [0.80, 1.48]3.03 [2.81, 3.26]30% [26%, 34%]55%71%+0.00+0.292026-08-02 → 2026-08-30
tmin00Zbilinearall23 2 QC2.33 [2.14, 2.54]0.53+1.16 [0.68, 1.50]3.03 [2.79, 3.29]30% [26%, 34%]55%71%+0.00+0.292026-08-02 → 2026-08-30
tmin00Znearest30d23 2 QC2.46 [2.29, 2.67]0.55+1.28 [0.93, 1.59]3.28 [3.05, 3.51]30% [26%, 34%]54%68%-0.06+0.262026-08-02 → 2026-08-30
tmin00Znearest90d23 2 QC2.46 [2.28, 2.68]0.55+1.28 [0.86, 1.61]3.28 [3.05, 3.54]30% [25%, 34%]54%68%-0.06+0.262026-08-02 → 2026-08-30
tmin00Znearest365d23 2 QC2.46 [2.26, 2.69]0.55+1.28 [0.90, 1.62]3.28 [3.03, 3.55]30% [25%, 35%]54%68%-0.06+0.262026-08-02 → 2026-08-30
tmin00Znearestall23 2 QC2.46 [2.25, 2.71]0.55+1.28 [0.77, 1.63]3.28 [3.01, 3.56]30% [25%, 35%]54%68%-0.06+0.262026-08-02 → 2026-08-30
tmin12Zbilinear30d24 2 QC2.16 [2.02, 2.32]0.53+0.92 [0.53, 1.23]2.83 [2.66, 2.99]33% [29%, 36%]58%74%+0.06+0.262026-08-02 → 2026-08-30
tmin12Zbilinear90d24 2 QC2.16 [2.01, 2.34]0.53+0.92 [0.42, 1.24]2.83 [2.65, 3.01]33% [29%, 36%]58%74%+0.06+0.262026-08-02 → 2026-08-30
tmin12Zbilinear365d24 2 QC2.16 [2.00, 2.33]0.53+0.92 [0.50, 1.26]2.83 [2.65, 3.00]33% [29%, 37%]58%74%+0.06+0.262026-08-02 → 2026-08-30
tmin12Zbilinearall24 2 QC2.16 [1.98, 2.34]0.53+0.92 [0.37, 1.25]2.83 [2.62, 3.02]33% [29%, 37%]58%74%+0.06+0.262026-08-02 → 2026-08-30
tmin12Znearest30d24 2 QC2.30 [2.13, 2.48]0.55+1.00 [0.58, 1.34]3.04 [2.83, 3.24]32% [28%, 35%]56%70%+0.00+0.232026-08-02 → 2026-08-30
tmin12Znearest90d24 2 QC2.30 [2.12, 2.49]0.55+1.00 [0.49, 1.36]3.04 [2.84, 3.27]32% [28%, 35%]56%70%+0.00+0.232026-08-02 → 2026-08-30
tmin12Znearest365d24 2 QC2.30 [2.11, 2.48]0.55+1.00 [0.52, 1.37]3.04 [2.83, 3.27]32% [27%, 36%]56%70%+0.00+0.232026-08-02 → 2026-08-30
tmin12Znearestall24 2 QC2.30 [2.10, 2.48]0.55+1.00 [0.39, 1.36]3.04 [2.80, 3.27]32% [28%, 36%]56%70%+0.00+0.232026-08-02 → 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 1, 00Z bilinear tmax+5+2.50-2.5-52026-08-02: -2.86 °F2026-08-09: -2.49 °F2026-08-10: -1.31 °F2026-08-11: -1.83 °F2026-08-12: -3.19 °F2026-08-13: -2.84 °F2026-08-14: -2.96 °F2026-08-15: -1.23 °F2026-08-16: -1.75 °F2026-08-17: -3.56 °F2026-08-18: -2.82 °F2026-08-19: -2.86 °F2026-08-20: -4.04 °F2026-08-21: -1.96 °F2026-08-22: -2.21 °F2026-08-23: -2.89 °F2026-08-24: -3.71 °F2026-08-25: -2.76 °F2026-08-26: -3.09 °F2026-08-27: -3.9 °F2026-08-28: -4.54 °F2026-08-29: -3.82 °F2026-08-30: -2.46 °F2026-08-022026-08-30°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 (29 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-2.46
2026-08-29-3.82
2026-08-28-4.54
2026-08-27-3.90
2026-08-26-3.09
2026-08-25-2.76
2026-08-24-3.71
2026-08-23-2.89
2026-08-22-2.21
2026-08-21-1.96
2026-08-20-4.04
2026-08-19-2.86
2026-08-18-2.82
2026-08-17-3.56
2026-08-16-1.75
2026-08-15-1.23
2026-08-14-2.96
2026-08-13-2.84
2026-08-12-3.19
2026-08-11-1.83
2026-08-10-1.31
2026-08-09-2.49
2026-08-08—
2026-08-07—
2026-08-06—
2026-08-05—
2026-08-04—
2026-08-03—
2026-08-02-2.86

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at ALL, lead day 1-5 to -4.5 °F: 1 day-4.5 to -4 °F: 1 day-4 to -3.5 °F: 4 days-3.5 to -3 °F: 2 days-3 to -2.5 °F: 7 days-2.5 to -2 °F: 3 days-2 to -1.5 °F: 3 days-1.5 to -1 °F: 2 days-1 to -0.5 °F: 0 days-0.5 to 0 °F: 0 days0 to 0.5 °F: 0 days0.5 to 1 °F: 0 days1 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: 0 daysdashed: P50 |e| 2.86 · P90 |e| 3.88 °F-50+5 °Fn = 23 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
-5.00-4.501
-4.50-4.001
-4.00-3.504
-3.50-3.002
-3.00-2.507
-2.50-2.003
-2.00-1.503
-1.50-1.002
-1.00-0.500
-0.50+0.000
+0.00+0.500
+0.50+1.000
+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+5.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08232.83 -2.83

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-02 → 2026-08-30 23
ECMWF IFS HRES2026-08-02 → 2026-08-30 23
ECMWF IFS HRES2026-08-02 → 2026-08-30 24
ECMWF IFS HRES2026-08-02 → 2026-08-30 24

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 23 +0.10 [-0.00, 0.20] no
Aurora (GFS init) 1 -2.99 [-2.99, -2.99] yes
Aurora (IFS init) 2 -1.61 [-1.77, -1.45] yes
FourCastNet v2 (GFS init) 1 -0.60 [-0.60, -0.60] yes
FourCastNet v2 (IFS init) 2 -0.33 [-0.37, -0.30] yes
NCEP GFS 23 +0.56 [0.28, 0.73] yes
GraphCast (GFS init) 1 -2.65 [-2.65, -2.65] yes
GraphCast (IFS init) 21 -1.45 [-1.60, -1.29] yes
Pangu-Weather (GFS init) 1 -0.21 [-0.21, -0.21] yes
Pangu-Weather (IFS init) 2 -0.42 [-0.45, -0.39] yes
Persistence (baseline) 23 +0.89 [0.62, 1.13] yes

Cite this page

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

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 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/ifs_hres/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