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

Seattle-Tacoma · ECMWF IFS HRES · lead day 7

KSEA · ifs_hres · lead 7

Target day = initialization date + 7 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, 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
tmax00Zbilinear30d18 1 QC4.72 [2.74, 5.91]4.85-1.10 [-4.55, 4.00]5.83 [3.36, 7.04]17% [5%, 40%]28%33%+0.06+0.052026-08-08 → 2026-08-30
tmax00Zbilinear90d18 1 QC4.72 [1.83, 5.97]4.85-1.10 [-4.56, 4.49]5.83 [2.27, 7.08]17% [3%, 53%]28%33%+0.06+0.052026-08-08 → 2026-08-30
tmax00Zbilinear365d18 1 QC4.72 [1.91, 6.14]4.85-1.10 [-4.86, 4.50]5.83 [2.38, 7.27]17% [0%, 50%]28%33%+0.06+0.052026-08-08 → 2026-08-30
tmax00Zbilinearall18 1 QC4.72 [1.94, 6.11]4.85-1.10 [-5.22, 4.75]5.83 [2.38, 7.16]17% [0%, 50%]28%33%+0.06+0.052026-08-08 → 2026-08-30
tmax00Znearest30d18 1 QC4.65 [2.67, 5.90]4.79-1.20 [-4.58, 3.81]5.83 [3.32, 7.09]11% [0%, 33%]28%33%+0.07+0.062026-08-08 → 2026-08-30
tmax00Znearest90d18 1 QC4.65 [1.81, 5.93]4.79-1.20 [-4.58, 4.35]5.83 [2.19, 7.11]11% [0%, 50%]28%33%+0.07+0.062026-08-08 → 2026-08-30
tmax00Znearest365d18 1 QC4.65 [1.87, 6.10]4.79-1.20 [-4.90, 4.36]5.83 [2.33, 7.34]11% [0%, 50%]28%33%+0.07+0.062026-08-08 → 2026-08-30
tmax00Znearestall18 1 QC4.65 [1.87, 6.08]4.79-1.20 [-5.27, 4.61]5.83 [2.33, 7.20]11% [0%, 44%]28%33%+0.07+0.062026-08-08 → 2026-08-30
tmax12Zbilinear30d17 1 QC3.34 [1.88, 5.06]3.13-0.70 [-2.99, 3.30]4.28 [2.16, 5.74]12% [0%, 25%]41%59%+0.34+0.392026-08-08 → 2026-08-30
tmax12Zbilinear90d17 1 QC3.34 [1.69, 5.05]3.13-0.70 [-3.23, 3.65]4.28 [1.93, 5.76]12% [0%, 29%]41%59%+0.34+0.392026-08-08 → 2026-08-30
tmax12Zbilinear365d17 1 QC3.34 [1.73, 5.33]3.13-0.70 [-3.23, 3.67]4.28 [1.97, 6.04]12% [0%, 27%]41%59%+0.34+0.392026-08-08 → 2026-08-30
tmax12Zbilinearall17 1 QC3.34 [1.65, 5.38]3.13-0.70 [-3.40, 3.98]4.28 [1.88, 5.92]12% [0%, 33%]41%59%+0.34+0.392026-08-08 → 2026-08-30
tmax12Znearest30d17 1 QC3.42 [2.02, 4.97]3.09-1.07 [-3.31, 2.87]4.33 [2.40, 5.67]12% [0%, 25%]29%53%+0.32+0.402026-08-08 → 2026-08-30
tmax12Znearest90d17 1 QC3.42 [1.89, 4.93]3.09-1.07 [-3.56, 3.26]4.33 [2.22, 5.70]12% [0%, 29%]29%53%+0.32+0.402026-08-08 → 2026-08-30
tmax12Znearest365d17 1 QC3.42 [1.86, 5.19]3.09-1.07 [-3.56, 3.33]4.33 [2.25, 5.89]12% [0%, 27%]29%53%+0.32+0.402026-08-08 → 2026-08-30
tmax12Znearestall17 1 QC3.42 [1.83, 5.17]3.09-1.07 [-3.71, 3.60]4.33 [2.15, 5.79]12% [0%, 33%]29%53%+0.32+0.402026-08-08 → 2026-08-30
tmin00Zbilinear30d18 1 QC2.64 [1.56, 4.59]2.41+1.53 [-0.07, 4.43]3.38 [1.80, 5.14]22% [10%, 31%]56%61%-0.13-0.032026-08-08 → 2026-08-30
tmin00Zbilinear90d18 1 QC2.64 [1.48, 5.80]2.41+1.53 [-0.42, 5.80]3.38 [1.72, 5.88]22% [0%, 33%]56%61%-0.13-0.032026-08-08 → 2026-08-30
tmin00Zbilinear365d18 1 QC2.64 [1.44, 5.81]2.41+1.53 [-0.44, 5.81]3.38 [1.66, 5.89]22% [0%, 32%]56%61%-0.13-0.032026-08-08 → 2026-08-30
tmin00Zbilinearall18 1 QC2.64 [1.40, 5.68]2.41+1.53 [-0.58, 5.68]3.38 [1.64, 5.81]22% [0%, 33%]56%61%-0.13-0.032026-08-08 → 2026-08-30
tmin00Znearest30d18 1 QC2.96 [1.68, 5.37]2.45+2.18 [0.49, 5.20]3.79 [1.80, 5.96]11% [0%, 22%]56%67%-0.27-0.052026-08-08 → 2026-08-30
tmin00Znearest90d18 1 QC2.96 [1.60, 6.87]2.45+2.18 [0.13, 6.87]3.79 [1.72, 6.96]11% [0%, 22%]56%67%-0.27-0.052026-08-08 → 2026-08-30
tmin00Znearest365d18 1 QC2.96 [1.57, 6.88]2.45+2.18 [0.13, 6.88]3.79 [1.71, 6.98]11% [0%, 22%]56%67%-0.27-0.052026-08-08 → 2026-08-30
tmin00Znearestall18 1 QC2.96 [1.55, 6.71]2.45+2.18 [-0.02, 6.71]3.79 [1.69, 6.84]11% [0%, 25%]56%67%-0.27-0.052026-08-08 → 2026-08-30
tmin12Zbilinear30d17 1 QC2.04 [1.26, 3.55]1.91+1.11 [-0.22, 3.40]2.71 [1.43, 4.24]24% [10%, 35%]59%82%+0.11+0.162026-08-08 → 2026-08-30
tmin12Zbilinear90d17 1 QC2.04 [1.25, 3.82]1.91+1.11 [-0.53, 3.69]2.71 [1.41, 4.50]24% [0%, 37%]59%82%+0.11+0.162026-08-08 → 2026-08-30
tmin12Zbilinear365d17 1 QC2.04 [1.22, 3.78]1.91+1.11 [-0.46, 3.64]2.71 [1.39, 4.43]24% [0%, 36%]59%82%+0.11+0.162026-08-08 → 2026-08-30
tmin12Zbilinearall17 1 QC2.04 [1.21, 3.68]1.91+1.11 [-0.48, 3.64]2.71 [1.35, 4.42]24% [0%, 36%]59%82%+0.11+0.162026-08-08 → 2026-08-30
tmin12Znearest30d17 1 QC2.30 [1.31, 4.16]1.91+1.73 [0.31, 4.09]3.05 [1.48, 4.88]24% [10%, 36%]65%76%-0.00+0.162026-08-08 → 2026-08-30
tmin12Znearest90d17 1 QC2.30 [1.25, 4.50]1.91+1.73 [0.06, 4.42]3.05 [1.38, 5.14]24% [0%, 38%]65%76%-0.00+0.162026-08-08 → 2026-08-30
tmin12Znearest365d17 1 QC2.30 [1.23, 4.39]1.91+1.73 [0.09, 4.31]3.05 [1.36, 5.07]24% [0%, 38%]65%76%-0.00+0.162026-08-08 → 2026-08-30
tmin12Znearestall17 1 QC2.30 [1.23, 4.39]1.91+1.73 [0.05, 4.39]3.05 [1.35, 5.08]24% [0%, 37%]65%76%-0.00+0.162026-08-08 → 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 7, 00Z bilinear tmax+20+100-10-202026-08-08: +0.4 °F2026-08-14: +4.4 °F2026-08-15: +11.53 °F2026-08-16: +3.3 °F2026-08-17: +2.84 °F2026-08-18: +0.78 °F2026-08-19: -7.33 °F2026-08-20: -12.52 °F2026-08-21: -1.05 °F2026-08-22: -5.4 °F2026-08-23: -5.94 °F2026-08-24: -6.61 °F2026-08-25: -7.86 °F2026-08-26: -5.67 °F2026-08-27: +1.76 °F2026-08-28: +0.97 °F2026-08-29: +3.14 °F2026-08-30: +3.43 °F2026-08-082026-08-30°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 (23 days, newest first) · download CSV
Climatological dayError °F
2026-08-30+3.43
2026-08-29+3.14
2026-08-28+0.97
2026-08-27+1.76
2026-08-26-5.67
2026-08-25-7.86
2026-08-24-6.61
2026-08-23-5.94
2026-08-22-5.40
2026-08-21-1.05
2026-08-20-12.52
2026-08-19-7.33
2026-08-18+0.78
2026-08-17+2.84
2026-08-16+3.30
2026-08-15+11.53
2026-08-14+4.40
2026-08-13—
2026-08-12—
2026-08-11—
2026-08-10—
2026-08-09—
2026-08-08+0.40

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KSEA, lead day 7-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 1 day-12 to -10 °F: 0 days-10 to -8 °F: 0 days-8 to -6 °F: 3 days-6 to -4 °F: 3 days-4 to -2 °F: 0 days-2 to 0 °F: 1 day0 to 2 °F: 4 days2 to 4 °F: 4 days4 to 6 °F: 1 day6 to 8 °F: 0 days8 to 10 °F: 0 days10 to 12 °F: 1 day12 to 14 °F: 0 days14 to 16 °F: 0 days16 to 18 °F: 0 days18 to 20 °F: 0 daysdashed: P50 |e| 3.91 · P90 |e| 8.96 °F-200+20 °Fn = 18 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
-20.00-18.000
-18.00-16.000
-16.00-14.000
-14.00-12.001
-12.00-10.000
-10.00-8.000
-8.00-6.003
-6.00-4.003
-4.00-2.000
-2.00+0.001
+0.00+2.004
+2.00+4.004
+4.00+6.001
+6.00+8.000
+8.00+10.000
+10.00+12.001
+12.00+14.000
+14.00+16.000
+16.00+18.000
+18.00+20.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08184.72 -1.10

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-08 → 2026-08-30 18
ECMWF IFS HRES2026-08-08 → 2026-08-30 18
ECMWF IFS HRES2026-08-08 → 2026-08-30 17
ECMWF IFS HRES2026-08-08 → 2026-08-30 17

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 18 -1.68 [-3.37, 1.85] no
NCEP GFS 18 +0.45 [-2.59, 2.55] no
GraphCast (IFS init) 18 -2.07 [-6.03, 1.02] no
Persistence (baseline) 18 -0.28 [-6.60, 2.31] no

Cite this page

ShortCastCheck, KSEA ifs_hres lead 7, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KSEA/model/ifs_hres/lead/7/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSEA (Seattle-Tacoma), model ifs_hres, lead day 7. 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/7/

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