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

Seattle-Tacoma · ECMWF IFS HRES · lead day 1

KSEA · 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, 1 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
tmax00Zbilinear30d22 1 QC2.39 [1.64, 3.14]2.26-0.62 [-1.62, 0.58]2.94 [1.92, 3.62]27% [11%, 38%]50%68%+0.15+0.192026-08-02 → 2026-08-30
tmax00Zbilinear90d22 1 QC2.39 [1.56, 3.07]2.26-0.62 [-1.63, 0.50]2.94 [1.63, 3.59]27% [9%, 39%]50%68%+0.15+0.192026-08-02 → 2026-08-30
tmax00Zbilinear365d22 1 QC2.39 [1.57, 3.14]2.26-0.62 [-1.66, 0.59]2.94 [1.62, 3.60]27% [8%, 40%]50%68%+0.15+0.192026-08-02 → 2026-08-30
tmax00Zbilinearall22 1 QC2.39 [1.55, 3.10]2.26-0.62 [-1.76, 0.61]2.94 [1.58, 3.57]27% [0%, 40%]50%68%+0.15+0.192026-08-02 → 2026-08-30
tmax00Znearest30d22 1 QC2.58 [1.93, 3.26]2.46-0.83 [-1.86, 0.37]3.14 [2.24, 3.76]32% [12%, 48%]41%64%+0.09+0.112026-08-02 → 2026-08-30
tmax00Znearest90d22 1 QC2.58 [1.83, 3.23]2.46-0.83 [-1.98, 0.27]3.14 [2.14, 3.75]32% [9%, 50%]41%64%+0.09+0.112026-08-02 → 2026-08-30
tmax00Znearest365d22 1 QC2.58 [1.82, 3.31]2.46-0.83 [-2.01, 0.37]3.14 [2.09, 3.78]32% [8%, 50%]41%64%+0.09+0.112026-08-02 → 2026-08-30
tmax00Znearestall22 1 QC2.58 [1.86, 3.24]2.46-0.83 [-2.20, 0.40]3.14 [2.11, 3.74]32% [0%, 50%]41%64%+0.09+0.112026-08-02 → 2026-08-30
tmax12Zbilinear30d24 1 QC1.99 [1.32, 2.61]1.94-0.73 [-1.51, 0.14]2.59 [1.70, 3.13]33% [19%, 48%]62%75%+0.33+0.322026-08-02 → 2026-08-30
tmax12Zbilinear90d24 1 QC1.99 [1.15, 2.59]1.94-0.73 [-1.58, 0.08]2.59 [1.40, 3.11]33% [14%, 50%]62%75%+0.33+0.322026-08-02 → 2026-08-30
tmax12Zbilinear365d24 1 QC1.99 [1.21, 2.62]1.94-0.73 [-1.62, 0.13]2.59 [1.40, 3.15]33% [13%, 50%]62%75%+0.33+0.322026-08-02 → 2026-08-30
tmax12Zbilinearall24 1 QC1.99 [1.24, 2.62]1.94-0.73 [-1.74, 0.13]2.59 [1.42, 3.12]33% [12%, 50%]62%75%+0.33+0.322026-08-02 → 2026-08-30
tmax12Znearest30d24 1 QC2.08 [1.41, 2.69]2.00-0.97 [-1.77, -0.12]2.71 [1.93, 3.20]38% [21%, 53%]50%75%+0.30+0.292026-08-02 → 2026-08-30
tmax12Znearest90d24 1 QC2.08 [1.35, 2.72]2.00-0.97 [-1.87, -0.18]2.71 [1.72, 3.19]38% [17%, 55%]50%75%+0.30+0.292026-08-02 → 2026-08-30
tmax12Znearest365d24 1 QC2.08 [1.33, 2.74]2.00-0.97 [-1.91, -0.13]2.71 [1.73, 3.23]38% [17%, 56%]50%75%+0.30+0.292026-08-02 → 2026-08-30
tmax12Znearestall24 1 QC2.08 [1.40, 2.74]2.00-0.97 [-2.06, -0.13]2.71 [1.73, 3.21]38% [14%, 55%]50%75%+0.30+0.292026-08-02 → 2026-08-30
tmin00Zbilinear30d22 1 QC1.48 [0.88, 2.08]1.03+1.37 [0.60, 2.04]1.89 [1.14, 2.43]36% [15%, 60%]77%86%+0.04+0.342026-08-02 → 2026-08-30
tmin00Zbilinear90d22 1 QC1.48 [0.83, 2.13]1.03+1.37 [0.38, 2.04]1.89 [0.97, 2.48]36% [15%, 67%]77%86%+0.04+0.342026-08-02 → 2026-08-30
tmin00Zbilinear365d22 1 QC1.48 [0.80, 2.15]1.03+1.37 [0.47, 2.09]1.89 [0.97, 2.48]36% [13%, 67%]77%86%+0.04+0.342026-08-02 → 2026-08-30
tmin00Zbilinearall22 1 QC1.48 [0.78, 2.18]1.03+1.37 [0.19, 2.10]1.89 [0.93, 2.51]36% [13%, 71%]77%86%+0.04+0.342026-08-02 → 2026-08-30
tmin00Znearest30d22 1 QC1.86 [1.09, 2.66]1.08+1.83 [0.97, 2.64]2.30 [1.39, 2.98]27% [5%, 53%]59%86%-0.21+0.312026-08-02 → 2026-08-30
tmin00Znearest90d22 1 QC1.86 [0.93, 2.70]1.08+1.83 [0.78, 2.67]2.30 [1.23, 3.03]27% [7%, 58%]59%86%-0.21+0.312026-08-02 → 2026-08-30
tmin00Znearest365d22 1 QC1.86 [0.94, 2.75]1.08+1.83 [0.88, 2.71]2.30 [1.26, 3.04]27% [5%, 57%]59%86%-0.21+0.312026-08-02 → 2026-08-30
tmin00Znearestall22 1 QC1.86 [0.82, 2.77]1.08+1.83 [0.59, 2.71]2.30 [1.10, 3.08]27% [4%, 67%]59%86%-0.21+0.312026-08-02 → 2026-08-30
tmin12Zbilinear30d24 1 QC1.60 [0.97, 2.20]1.09+1.43 [0.61, 2.16]1.93 [1.25, 2.46]33% [13%, 53%]62%92%-0.01+0.322026-08-02 → 2026-08-30
tmin12Zbilinear90d24 1 QC1.60 [0.87, 2.22]1.09+1.43 [0.40, 2.14]1.93 [1.12, 2.45]33% [12%, 60%]62%92%-0.01+0.322026-08-02 → 2026-08-30
tmin12Zbilinear365d24 1 QC1.60 [0.86, 2.24]1.09+1.43 [0.38, 2.19]1.93 [1.11, 2.49]33% [11%, 58%]62%92%-0.01+0.322026-08-02 → 2026-08-30
tmin12Zbilinearall24 1 QC1.60 [0.82, 2.22]1.09+1.43 [0.24, 2.18]1.93 [1.06, 2.50]33% [11%, 62%]62%92%-0.01+0.322026-08-02 → 2026-08-30
tmin12Znearest30d24 1 QC2.03 [1.18, 2.84]1.23+1.93 [0.94, 2.84]2.43 [1.56, 3.05]29% [7%, 53%]42%79%-0.28+0.232026-08-02 → 2026-08-30
tmin12Znearest90d24 1 QC2.03 [1.05, 2.84]1.23+1.93 [0.68, 2.83]2.43 [1.40, 3.05]29% [6%, 58%]42%79%-0.28+0.232026-08-02 → 2026-08-30
tmin12Znearest365d24 1 QC2.03 [1.04, 2.88]1.23+1.93 [0.68, 2.88]2.43 [1.40, 3.09]29% [3%, 57%]42%79%-0.28+0.232026-08-02 → 2026-08-30
tmin12Znearestall24 1 QC2.03 [0.89, 2.89]1.23+1.93 [0.51, 2.88]2.43 [1.30, 3.08]29% [0%, 62%]42%79%-0.28+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 KSEA, lead day 1, 00Z bilinear tmax+10+50-5-102026-08-02: -1.57 °F2026-08-10: +2.49 °F2026-08-11: -1.91 °F2026-08-12: -3.35 °F2026-08-13: -0.47 °F2026-08-14: +4.46 °F2026-08-15: +5.27 °F2026-08-16: +3.41 °F2026-08-17: -2.92 °F2026-08-18: +0.31 °F2026-08-19: -5.1 °F2026-08-20: -5.51 °F2026-08-21: +1.48 °F2026-08-22: +0.33 °F2026-08-23: -0.75 °F2026-08-24: -5 °F2026-08-25: -0.39 °F2026-08-26: +1.74 °F2026-08-27: -2.23 °F2026-08-28: -1.28 °F2026-08-29: -0.61 °F2026-08-30: -2.07 °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
2026-08-30-2.07
2026-08-29-0.61
2026-08-28-1.28
2026-08-27-2.23
2026-08-26+1.74
2026-08-25-0.39
2026-08-24-5.00
2026-08-23-0.75
2026-08-22+0.33
2026-08-21+1.48
2026-08-20-5.51
2026-08-19-5.10
2026-08-18+0.31
2026-08-17-2.92
2026-08-16+3.41
2026-08-15+5.27
2026-08-14+4.46
2026-08-13-0.47
2026-08-12-3.35
2026-08-11-1.91
2026-08-10+2.49
2026-08-09—
2026-08-08—
2026-08-07—
2026-08-06—
2026-08-05—
2026-08-04—
2026-08-03—
2026-08-02-1.57

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KSEA, 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: 1 day-4 to -3 °F: 1 day-3 to -2 °F: 3 days-2 to -1 °F: 3 days-1 to 0 °F: 4 days0 to 1 °F: 2 days1 to 2 °F: 2 days2 to 3 °F: 1 day3 to 4 °F: 1 day4 to 5 °F: 1 day5 to 6 °F: 1 day6 to 7 °F: 0 days7 to 8 °F: 0 days8 to 9 °F: 0 days9 to 10 °F: 0 daysdashed: P50 |e| 1.99 · P90 |e| 5.09 °F-100+10 °Fn = 22 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
-5.00-4.001
-4.00-3.001
-3.00-2.003
-2.00-1.003
-1.00+0.004
+0.00+1.002
+1.00+2.002
+2.00+3.001
+3.00+4.001
+4.00+5.001
+5.00+6.001
+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
2026-08222.39 -0.62

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-02 → 2026-08-30 22
ECMWF IFS HRES2026-08-02 → 2026-08-30 22
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 22 -3.21 [-4.10, -1.64] yes
Aurora (GFS init) 1 -2.43 [-2.43, -2.43] yes
Aurora (IFS init) 2 -2.57 [-5.76, 0.62] no
FourCastNet v2 (GFS init) 1 +0.33 [0.33, 0.33] yes
FourCastNet v2 (IFS init) 2 -0.36 [-2.67, 1.95] no
NCEP GFS 22 -1.91 [-3.24, -0.77] yes
GraphCast (GFS init) 1 -2.35 [-2.35, -2.35] yes
GraphCast (IFS init) 20 -2.24 [-3.32, -1.22] yes
Pangu-Weather (GFS init) 1 -0.34 [-0.34, -0.34] yes
Pangu-Weather (IFS init) 2 -1.72 [-3.85, 0.40] no
Persistence (baseline) 22 -0.42 [-1.63, 0.76] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSEA (Seattle-Tacoma), 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/KSEA/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