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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 6

ALL · ifs_hres · lead 6

Target day = initialization date + 6 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
tmax00Zbilinear30d19 2 QC4.03 [3.71, 4.33]0.83-2.21 [-2.65, -1.62]4.95 [4.50, 5.34]13% [11%, 16%]27%43%-0.01+0.432026-08-07 → 2026-08-30
tmax00Zbilinear90d19 2 QC4.03 [3.68, 4.34]0.83-2.21 [-2.69, -1.63]4.95 [4.48, 5.35]13% [11%, 16%]27%43%-0.01+0.432026-08-07 → 2026-08-30
tmax00Zbilinear365d19 2 QC4.03 [3.68, 4.36]0.83-2.21 [-2.67, -1.59]4.95 [4.47, 5.38]13% [11%, 16%]27%43%-0.01+0.432026-08-07 → 2026-08-30
tmax00Zbilinearall19 2 QC4.03 [3.68, 4.32]0.83-2.21 [-2.68, -1.55]4.95 [4.48, 5.36]13% [10%, 16%]27%43%-0.01+0.432026-08-07 → 2026-08-30
tmax00Znearest30d19 2 QC4.27 [3.97, 4.56]0.86-2.26 [-2.77, -1.57]5.24 [4.81, 5.62]12% [10%, 15%]25%39%-0.07+0.422026-08-07 → 2026-08-30
tmax00Znearest90d19 2 QC4.27 [3.95, 4.57]0.86-2.26 [-2.79, -1.56]5.24 [4.78, 5.64]12% [10%, 15%]25%39%-0.07+0.422026-08-07 → 2026-08-30
tmax00Znearest365d19 2 QC4.27 [3.94, 4.57]0.86-2.26 [-2.79, -1.51]5.24 [4.76, 5.65]12% [9%, 15%]25%39%-0.07+0.422026-08-07 → 2026-08-30
tmax00Znearestall19 2 QC4.27 [3.94, 4.56]0.86-2.26 [-2.79, -1.47]5.24 [4.77, 5.63]12% [10%, 15%]25%39%-0.07+0.422026-08-07 → 2026-08-30
tmax12Zbilinear30d19 2 QC3.79 [3.66, 3.94]0.77-2.55 [-3.01, -2.03]4.69 [4.46, 4.91]13% [11%, 16%]30%46%+0.05+0.482026-08-07 → 2026-08-30
tmax12Zbilinear90d19 2 QC3.79 [3.65, 4.02]0.77-2.55 [-3.07, -2.03]4.69 [4.42, 5.05]13% [11%, 17%]30%46%+0.05+0.482026-08-07 → 2026-08-30
tmax12Zbilinear365d19 2 QC3.79 [3.64, 4.02]0.77-2.55 [-3.12, -1.98]4.69 [4.39, 5.03]13% [11%, 17%]30%46%+0.05+0.482026-08-07 → 2026-08-30
tmax12Zbilinearall19 2 QC3.79 [3.64, 4.00]0.77-2.55 [-3.20, -1.97]4.69 [4.39, 5.02]13% [11%, 17%]30%46%+0.05+0.482026-08-07 → 2026-08-30
tmax12Znearest30d19 2 QC3.96 [3.83, 4.15]0.78-2.58 [-3.04, -2.00]4.95 [4.75, 5.16]13% [11%, 15%]30%46%+0.01+0.472026-08-07 → 2026-08-30
tmax12Znearest90d19 2 QC3.96 [3.81, 4.28]0.78-2.58 [-3.09, -1.98]4.95 [4.71, 5.30]13% [11%, 15%]30%46%+0.01+0.472026-08-07 → 2026-08-30
tmax12Znearest365d19 2 QC3.96 [3.79, 4.28]0.78-2.58 [-3.10, -1.92]4.95 [4.70, 5.28]13% [11%, 15%]30%46%+0.01+0.472026-08-07 → 2026-08-30
tmax12Znearestall19 2 QC3.96 [3.80, 4.23]0.78-2.58 [-3.10, -1.90]4.95 [4.68, 5.26]13% [11%, 15%]30%46%+0.01+0.472026-08-07 → 2026-08-30
tmin00Zbilinear30d19 2 QC2.98 [2.71, 3.19]0.73+1.74 [1.35, 2.09]3.96 [3.58, 4.23]24% [22%, 26%]47%61%+0.15+0.292026-08-07 → 2026-08-30
tmin00Zbilinear90d19 2 QC2.98 [2.66, 3.23]0.73+1.74 [1.30, 2.13]3.96 [3.52, 4.27]24% [22%, 27%]47%61%+0.15+0.292026-08-07 → 2026-08-30
tmin00Zbilinear365d19 2 QC2.98 [2.66, 3.20]0.73+1.74 [1.31, 2.14]3.96 [3.50, 4.27]24% [22%, 27%]47%61%+0.15+0.292026-08-07 → 2026-08-30
tmin00Zbilinearall19 2 QC2.98 [2.67, 3.20]0.73+1.74 [1.28, 2.13]3.96 [3.49, 4.27]24% [22%, 27%]47%61%+0.15+0.292026-08-07 → 2026-08-30
tmin00Znearest30d19 2 QC3.13 [2.79, 3.36]0.76+1.78 [1.37, 2.16]4.19 [3.78, 4.50]22% [21%, 25%]45%60%+0.10+0.252026-08-07 → 2026-08-30
tmin00Znearest90d19 2 QC3.13 [2.73, 3.42]0.76+1.78 [1.33, 2.23]4.19 [3.68, 4.65]22% [21%, 27%]45%60%+0.10+0.252026-08-07 → 2026-08-30
tmin00Znearest365d19 2 QC3.13 [2.73, 3.38]0.76+1.78 [1.34, 2.24]4.19 [3.67, 4.65]22% [20%, 27%]45%60%+0.10+0.252026-08-07 → 2026-08-30
tmin00Znearestall19 2 QC3.13 [2.73, 3.38]0.76+1.78 [1.32, 2.22]4.19 [3.66, 4.65]22% [21%, 26%]45%60%+0.10+0.252026-08-07 → 2026-08-30
tmin12Zbilinear30d19 2 QC2.83 [2.58, 3.02]0.74+1.55 [1.08, 1.93]3.76 [3.42, 4.04]26% [24%, 30%]47%62%+0.19+0.272026-08-07 → 2026-08-30
tmin12Zbilinear90d19 2 QC2.83 [2.53, 3.04]0.74+1.55 [0.97, 1.95]3.76 [3.36, 4.07]26% [24%, 31%]47%62%+0.19+0.272026-08-07 → 2026-08-30
tmin12Zbilinear365d19 2 QC2.83 [2.53, 3.03]0.74+1.55 [0.95, 1.99]3.76 [3.33, 4.04]26% [23%, 31%]47%62%+0.19+0.272026-08-07 → 2026-08-30
tmin12Zbilinearall19 2 QC2.83 [2.55, 3.04]0.74+1.55 [1.01, 1.98]3.76 [3.33, 4.07]26% [24%, 31%]47%62%+0.19+0.272026-08-07 → 2026-08-30
tmin12Znearest30d19 2 QC2.98 [2.67, 3.19]0.77+1.61 [1.12, 2.01]3.97 [3.55, 4.28]23% [20%, 29%]47%62%+0.15+0.252026-08-07 → 2026-08-30
tmin12Znearest90d19 2 QC2.98 [2.60, 3.23]0.77+1.61 [1.03, 2.04]3.97 [3.49, 4.35]23% [19%, 34%]47%62%+0.15+0.252026-08-07 → 2026-08-30
tmin12Znearest365d19 2 QC2.98 [2.59, 3.22]0.77+1.61 [1.00, 2.07]3.97 [3.43, 4.31]23% [19%, 34%]47%62%+0.15+0.252026-08-07 → 2026-08-30
tmin12Znearestall19 2 QC2.98 [2.61, 3.22]0.77+1.61 [1.04, 2.07]3.97 [3.43, 4.35]23% [19%, 33%]47%62%+0.15+0.252026-08-07 → 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 6, 00Z bilinear tmax+5+2.50-2.5-52026-08-07: -2.25 °F2026-08-13: -1.31 °F2026-08-14: -2.13 °F2026-08-15: -2.02 °F2026-08-16: +0.1 °F2026-08-17: -0.81 °F2026-08-18: -2.75 °F2026-08-19: -3.48 °F2026-08-20: -1.09 °F2026-08-21: -1.41 °F2026-08-22: -3.32 °F2026-08-23: -3.6 °F2026-08-24: -3.45 °F2026-08-25: -1.85 °F2026-08-26: -3.55 °F2026-08-27: -1.89 °F2026-08-28: -2.39 °F2026-08-29: -1.77 °F2026-08-30: -3.02 °F2026-08-072026-08-30°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 (24 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-3.02
2026-08-29-1.77
2026-08-28-2.39
2026-08-27-1.89
2026-08-26-3.55
2026-08-25-1.85
2026-08-24-3.45
2026-08-23-3.60
2026-08-22-3.32
2026-08-21-1.41
2026-08-20-1.09
2026-08-19-3.48
2026-08-18-2.75
2026-08-17-0.81
2026-08-16+0.10
2026-08-15-2.02
2026-08-14-2.13
2026-08-13-1.31
2026-08-12—
2026-08-11—
2026-08-10—
2026-08-09—
2026-08-08—
2026-08-07-2.25

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at ALL, lead day 6-5 to -4.5 °F: 0 days-4.5 to -4 °F: 0 days-4 to -3.5 °F: 2 days-3.5 to -3 °F: 4 days-3 to -2.5 °F: 1 day-2.5 to -2 °F: 4 days-2 to -1.5 °F: 3 days-1.5 to -1 °F: 3 days-1 to -0.5 °F: 1 day-0.5 to 0 °F: 0 days0 to 0.5 °F: 1 day0.5 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| 2.13 · P90 |e| 3.49 °F-50+5 °Fn = 19 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
-4.50-4.000
-4.00-3.502
-3.50-3.004
-3.00-2.501
-2.50-2.004
-2.00-1.503
-1.50-1.003
-1.00-0.501
-0.50+0.000
+0.00+0.501
+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
2026-08192.22 -2.21

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-07 → 2026-08-30 19
ECMWF IFS HRES2026-08-07 → 2026-08-30 19
ECMWF IFS HRES2026-08-07 → 2026-08-30 19
ECMWF IFS HRES2026-08-07 → 2026-08-30 19

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 19 -0.11 [-0.59, 0.51] no
NCEP GFS 19 +0.32 [-0.13, 0.83] no
GraphCast (IFS init) 19 -1.74 [-2.37, -0.96] yes
Persistence (baseline) 19 +0.04 [-0.80, 0.55] no

Cite this page

ShortCastCheck, ALL ifs_hres lead 6, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/ALL/model/ifs_hres/lead/6/

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 6. 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/6/

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