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

Seattle-Tacoma · ECMWF IFS HRES · lead day 2

KSEA · ifs_hres · lead 2

Target day = initialization date + 2 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
tmax00Zbilinear30d23 1 QC2.41 [1.42, 3.23]2.21-0.80 [-2.31, 1.12]3.16 [1.94, 3.90]30% [12%, 53%]57%61%+0.52+0.542026-08-03 → 2026-08-30
tmax00Zbilinear90d23 1 QC2.41 [1.20, 3.20]2.21-0.80 [-2.34, 1.10]3.16 [1.60, 3.90]30% [8%, 56%]57%61%+0.52+0.542026-08-03 → 2026-08-30
tmax00Zbilinear365d23 1 QC2.41 [1.21, 3.27]2.21-0.80 [-2.52, 1.20]3.16 [1.52, 3.96]30% [6%, 56%]57%61%+0.52+0.542026-08-03 → 2026-08-30
tmax00Zbilinearall23 1 QC2.41 [1.21, 3.17]2.21-0.80 [-2.49, 1.22]3.16 [1.32, 3.87]30% [0%, 57%]57%61%+0.52+0.542026-08-03 → 2026-08-30
tmax00Znearest30d23 1 QC2.54 [1.58, 3.34]2.27-0.97 [-2.48, 0.90]3.25 [2.09, 3.96]26% [7%, 50%]52%61%+0.50+0.522026-08-03 → 2026-08-30
tmax00Znearest90d23 1 QC2.54 [1.42, 3.33]2.27-0.97 [-2.48, 0.89]3.25 [1.74, 4.00]26% [0%, 50%]52%61%+0.50+0.522026-08-03 → 2026-08-30
tmax00Znearest365d23 1 QC2.54 [1.40, 3.40]2.27-0.97 [-2.67, 0.96]3.25 [1.73, 4.04]26% [0%, 50%]52%61%+0.50+0.522026-08-03 → 2026-08-30
tmax00Znearestall23 1 QC2.54 [1.41, 3.31]2.27-0.97 [-2.69, 0.95]3.25 [1.74, 3.96]26% [0%, 50%]52%61%+0.50+0.522026-08-03 → 2026-08-30
tmax12Zbilinear30d22 1 QC2.42 [1.61, 3.12]2.25-0.74 [-1.98, 0.89]3.08 [2.13, 3.70]23% [8%, 38%]59%68%+0.52+0.532026-08-03 → 2026-08-30
tmax12Zbilinear90d22 1 QC2.42 [1.54, 3.11]2.25-0.74 [-2.08, 0.97]3.08 [1.87, 3.72]23% [6%, 38%]59%68%+0.52+0.532026-08-03 → 2026-08-30
tmax12Zbilinear365d22 1 QC2.42 [1.49, 3.17]2.25-0.74 [-2.21, 1.00]3.08 [1.80, 3.74]23% [5%, 40%]59%68%+0.52+0.532026-08-03 → 2026-08-30
tmax12Zbilinearall22 1 QC2.42 [1.48, 3.10]2.25-0.74 [-2.20, 1.00]3.08 [1.74, 3.68]23% [0%, 43%]59%68%+0.52+0.532026-08-03 → 2026-08-30
tmax12Znearest30d22 1 QC2.61 [1.82, 3.27]2.42-0.92 [-2.24, 0.74]3.29 [2.40, 3.87]14% [0%, 27%]55%68%+0.48+0.502026-08-03 → 2026-08-30
tmax12Znearest90d22 1 QC2.61 [1.77, 3.30]2.42-0.92 [-2.43, 0.74]3.29 [2.25, 3.90]14% [0%, 29%]55%68%+0.48+0.502026-08-03 → 2026-08-30
tmax12Znearest365d22 1 QC2.61 [1.72, 3.37]2.42-0.92 [-2.46, 0.85]3.29 [2.19, 3.94]14% [0%, 29%]55%68%+0.48+0.502026-08-03 → 2026-08-30
tmax12Znearestall22 1 QC2.61 [1.73, 3.25]2.42-0.92 [-2.54, 0.78]3.29 [2.19, 3.88]14% [0%, 29%]55%68%+0.48+0.502026-08-03 → 2026-08-30
tmin00Zbilinear30d23 1 QC1.63 [1.04, 2.20]1.04+1.57 [0.97, 2.18]2.05 [1.29, 2.61]35% [9%, 57%]65%78%+0.11+0.422026-08-03 → 2026-08-30
tmin00Zbilinear90d23 1 QC1.63 [0.97, 2.24]1.04+1.57 [0.90, 2.24]2.05 [1.22, 2.60]35% [0%, 59%]65%78%+0.11+0.422026-08-03 → 2026-08-30
tmin00Zbilinear365d23 1 QC1.63 [0.92, 2.25]1.04+1.57 [0.86, 2.25]2.05 [1.16, 2.65]35% [0%, 62%]65%78%+0.11+0.422026-08-03 → 2026-08-30
tmin00Zbilinearall23 1 QC1.63 [0.89, 2.27]1.04+1.57 [0.85, 2.27]2.05 [1.13, 2.64]35% [0%, 63%]65%78%+0.11+0.422026-08-03 → 2026-08-30
tmin00Znearest30d23 1 QC2.18 [1.41, 3.01]1.16+2.17 [1.39, 3.01]2.61 [1.68, 3.31]26% [4%, 46%]43%78%-0.20+0.362026-08-03 → 2026-08-30
tmin00Znearest90d23 1 QC2.18 [1.30, 3.12]1.16+2.17 [1.28, 3.12]2.61 [1.54, 3.34]26% [0%, 50%]43%78%-0.20+0.362026-08-03 → 2026-08-30
tmin00Znearest365d23 1 QC2.18 [1.25, 3.11]1.16+2.17 [1.23, 3.11]2.61 [1.50, 3.37]26% [0%, 50%]43%78%-0.20+0.362026-08-03 → 2026-08-30
tmin00Znearestall23 1 QC2.18 [1.25, 3.12]1.16+2.17 [1.22, 3.12]2.61 [1.52, 3.38]26% [0%, 52%]43%78%-0.20+0.362026-08-03 → 2026-08-30
tmin12Zbilinear30d22 1 QC1.45 [0.84, 2.11]1.06+1.43 [0.82, 2.10]1.91 [1.06, 2.51]50% [22%, 74%]68%86%+0.22+0.432026-08-03 → 2026-08-30
tmin12Zbilinear90d22 1 QC1.45 [0.79, 2.16]1.06+1.43 [0.77, 2.16]1.91 [0.92, 2.54]50% [17%, 76%]68%86%+0.22+0.432026-08-03 → 2026-08-30
tmin12Zbilinear365d22 1 QC1.45 [0.74, 2.18]1.06+1.43 [0.72, 2.18]1.91 [0.88, 2.57]50% [15%, 79%]68%86%+0.22+0.432026-08-03 → 2026-08-30
tmin12Zbilinearall22 1 QC1.45 [0.75, 2.19]1.06+1.43 [0.74, 2.19]1.91 [0.88, 2.57]50% [14%, 79%]68%86%+0.22+0.432026-08-03 → 2026-08-30
tmin12Znearest30d22 1 QC1.98 [1.23, 2.85]1.14+1.98 [1.23, 2.85]2.42 [1.46, 3.16]36% [12%, 58%]55%77%-0.06+0.392026-08-03 → 2026-08-30
tmin12Znearest90d22 1 QC1.98 [1.12, 2.95]1.14+1.98 [1.12, 2.95]2.42 [1.33, 3.23]36% [9%, 60%]55%77%-0.06+0.392026-08-03 → 2026-08-30
tmin12Znearest365d22 1 QC1.98 [1.08, 2.98]1.14+1.98 [1.08, 2.98]2.42 [1.25, 3.25]36% [6%, 62%]55%77%-0.06+0.392026-08-03 → 2026-08-30
tmin12Znearestall22 1 QC1.98 [1.09, 2.98]1.14+1.98 [1.09, 2.98]2.42 [1.27, 3.24]36% [0%, 62%]55%77%-0.06+0.392026-08-03 → 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 2, 00Z bilinear tmax+10+50-5-102026-08-03: -1.23 °F2026-08-08: -0.22 °F2026-08-09: -0.02 °F2026-08-10: +3.5 °F2026-08-11: -0.95 °F2026-08-13: -0.58 °F2026-08-14: +4.13 °F2026-08-15: +5.67 °F2026-08-16: +4.02 °F2026-08-17: -2.11 °F2026-08-18: -1.38 °F2026-08-19: -5.91 °F2026-08-20: -6.35 °F2026-08-21: -0.1 °F2026-08-22: -3.52 °F2026-08-23: -0.26 °F2026-08-24: -5.35 °F2026-08-25: -0.71 °F2026-08-26: +1.18 °F2026-08-27: -4.53 °F2026-08-28: -1.34 °F2026-08-29: -1.04 °F2026-08-30: -1.41 °F2026-08-032026-08-30°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 (28 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-1.41
2026-08-29-1.04
2026-08-28-1.34
2026-08-27-4.53
2026-08-26+1.18
2026-08-25-0.71
2026-08-24-5.35
2026-08-23-0.26
2026-08-22-3.52
2026-08-21-0.10
2026-08-20-6.35
2026-08-19-5.91
2026-08-18-1.38
2026-08-17-2.11
2026-08-16+4.02
2026-08-15+5.67
2026-08-14+4.13
2026-08-13-0.58
2026-08-12—
2026-08-11-0.95
2026-08-10+3.50
2026-08-09-0.02
2026-08-08-0.22
2026-08-07—
2026-08-06—
2026-08-05—
2026-08-04—
2026-08-03-1.23

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KSEA, lead day 2-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 1 day-6 to -5 °F: 2 days-5 to -4 °F: 1 day-4 to -3 °F: 1 day-3 to -2 °F: 1 day-2 to -1 °F: 5 days-1 to 0 °F: 7 days0 to 1 °F: 0 days1 to 2 °F: 1 day2 to 3 °F: 0 days3 to 4 °F: 1 day4 to 5 °F: 2 days5 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| 1.38 · P90 |e| 5.61 °F-100+10 °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
-10.00-9.000
-9.00-8.000
-8.00-7.000
-7.00-6.001
-6.00-5.002
-5.00-4.001
-4.00-3.001
-3.00-2.001
-2.00-1.005
-1.00+0.007
+0.00+1.000
+1.00+2.001
+2.00+3.000
+3.00+4.001
+4.00+5.002
+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
2026-08232.41 -0.80

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-03 → 2026-08-30 23
ECMWF IFS HRES2026-08-03 → 2026-08-30 23
ECMWF IFS HRES2026-08-03 → 2026-08-30 22
ECMWF IFS HRES2026-08-03 → 2026-08-30 22

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 -3.22 [-4.35, -1.75] yes
Aurora (IFS init) 1 -0.97 [-0.97, -0.97] yes
FourCastNet v2 (IFS init) 1 -0.12 [-0.12, -0.12] yes
NCEP GFS 23 -2.11 [-3.63, -0.75] yes
GraphCast (IFS init) 21 -2.18 [-3.12, -1.06] yes
Pangu-Weather (IFS init) 1 -0.87 [-0.87, -0.87] yes
Persistence (baseline) 23 -2.63 [-4.38, -1.05] yes

Cite this page

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

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

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