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

Trenton Mercer · ECMWF IFS HRES · lead day 7

KTTN · 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 QC2.74 [1.88, 4.35]2.74+1.02 [-0.95, 1.96]3.67 [2.62, 4.96]39% [5%, 67%]44%61%+0.32+0.132026-08-08 → 2026-08-30
tmax00Zbilinear90d18 1 QC2.74 [1.76, 4.84]2.74+1.02 [-2.49, 2.06]3.67 [2.66, 5.41]39% [0%, 69%]44%61%+0.32+0.132026-08-08 → 2026-08-30
tmax00Zbilinear365d18 1 QC2.74 [1.73, 5.23]2.74+1.02 [-1.94, 2.05]3.67 [2.40, 5.73]39% [0%, 70%]44%61%+0.32+0.132026-08-08 → 2026-08-30
tmax00Zbilinearall18 1 QC2.74 [1.77, 5.17]2.74+1.02 [-1.58, 2.06]3.67 [2.45, 5.66]39% [0%, 69%]44%61%+0.32+0.132026-08-08 → 2026-08-30
tmax00Znearest30d18 1 QC2.79 [1.82, 4.44]2.80+1.10 [-0.81, 2.16]3.68 [2.58, 5.08]33% [0%, 58%]44%56%+0.31+0.122026-08-08 → 2026-08-30
tmax00Znearest90d18 1 QC2.79 [1.75, 5.07]2.80+1.10 [-2.30, 2.24]3.68 [2.51, 5.52]33% [0%, 58%]44%56%+0.31+0.122026-08-08 → 2026-08-30
tmax00Znearest365d18 1 QC2.79 [1.74, 5.48]2.80+1.10 [-1.53, 2.26]3.68 [2.48, 5.77]33% [0%, 57%]44%56%+0.31+0.122026-08-08 → 2026-08-30
tmax00Znearestall18 1 QC2.79 [1.76, 5.32]2.80+1.10 [-1.47, 2.29]3.68 [2.51, 5.80]33% [0%, 57%]44%56%+0.31+0.122026-08-08 → 2026-08-30
tmax12Zbilinear30d17 1 QC3.88 [3.28, 4.47]3.64-1.41 [-3.05, 0.33]4.32 [3.43, 4.98]0% [0%, 0%]18%29%+0.08-0.172026-08-08 → 2026-08-30
tmax12Zbilinear90d17 1 QC3.88 [3.26, 4.60]3.64-1.41 [-3.54, 0.45]4.32 [3.42, 4.98]0% [0%, 0%]18%29%+0.08-0.172026-08-08 → 2026-08-30
tmax12Zbilinear365d17 1 QC3.88 [3.22, 4.62]3.64-1.41 [-3.54, 0.72]4.32 [3.38, 5.03]0% [0%, 0%]18%29%+0.08-0.172026-08-08 → 2026-08-30
tmax12Zbilinearall17 1 QC3.88 [3.27, 4.62]3.64-1.41 [-3.52, 0.74]4.32 [3.41, 5.00]0% [0%, 0%]18%29%+0.08-0.172026-08-08 → 2026-08-30
tmax12Znearest30d17 1 QC3.84 [3.27, 4.45]3.68-1.20 [-2.92, 0.65]4.34 [3.46, 4.98]6% [0%, 14%]18%35%+0.09-0.192026-08-08 → 2026-08-30
tmax12Znearest90d17 1 QC3.84 [3.24, 4.59]3.68-1.20 [-3.43, 0.79]4.34 [3.45, 4.99]6% [0%, 15%]18%35%+0.09-0.192026-08-08 → 2026-08-30
tmax12Znearest365d17 1 QC3.84 [3.19, 4.59]3.68-1.20 [-3.43, 0.91]4.34 [3.41, 5.08]6% [0%, 16%]18%35%+0.09-0.192026-08-08 → 2026-08-30
tmax12Znearestall17 1 QC3.84 [3.25, 4.59]3.68-1.20 [-3.44, 0.96]4.34 [3.40, 5.03]6% [0%, 15%]18%35%+0.09-0.192026-08-08 → 2026-08-30
tmin00Zbilinear30d18 1 QC5.33 [3.61, 6.94]3.08+5.33 [3.61, 6.94]6.38 [4.31, 8.15]6% [0%, 15%]11%44%-0.18+0.162026-08-08 → 2026-08-30
tmin00Zbilinear90d18 1 QC5.33 [2.56, 7.19]3.08+5.33 [2.56, 7.19]6.38 [2.65, 8.59]6% [0%, 16%]11%44%-0.18+0.162026-08-08 → 2026-08-30
tmin00Zbilinear365d18 1 QC5.33 [2.54, 7.30]3.08+5.33 [2.54, 7.30]6.38 [2.61, 8.62]6% [0%, 14%]11%44%-0.18+0.162026-08-08 → 2026-08-30
tmin00Zbilinearall18 1 QC5.33 [2.57, 7.63]3.08+5.33 [2.57, 7.63]6.38 [2.64, 8.86]6% [0%, 15%]11%44%-0.18+0.162026-08-08 → 2026-08-30
tmin00Znearest30d18 1 QC5.63 [3.95, 7.18]3.01+5.63 [3.95, 7.18]6.60 [4.58, 8.35]6% [0%, 15%]11%11%-0.25+0.182026-08-08 → 2026-08-30
tmin00Znearest90d18 1 QC5.63 [2.85, 7.44]3.01+5.63 [2.85, 7.44]6.60 [2.95, 8.78]6% [0%, 16%]11%11%-0.25+0.182026-08-08 → 2026-08-30
tmin00Znearest365d18 1 QC5.63 [2.85, 7.60]3.01+5.63 [2.85, 7.60]6.60 [2.95, 8.80]6% [0%, 14%]11%11%-0.25+0.182026-08-08 → 2026-08-30
tmin00Znearestall18 1 QC5.63 [2.89, 7.90]3.01+5.63 [2.89, 7.90]6.60 [2.98, 9.02]6% [0%, 15%]11%11%-0.25+0.182026-08-08 → 2026-08-30
tmin12Zbilinear30d17 1 QC4.61 [3.16, 6.47]2.79+4.61 [3.16, 6.47]5.66 [4.01, 7.51]12% [0%, 25%]29%41%-0.02+0.282026-08-08 → 2026-08-30
tmin12Zbilinear90d17 1 QC4.61 [3.09, 6.79]2.79+4.61 [3.09, 6.79]5.66 [3.09, 7.84]12% [0%, 25%]29%41%-0.02+0.282026-08-08 → 2026-08-30
tmin12Zbilinear365d17 1 QC4.61 [3.09, 6.78]2.79+4.61 [3.09, 6.78]5.66 [3.09, 7.90]12% [0%, 25%]29%41%-0.02+0.282026-08-08 → 2026-08-30
tmin12Zbilinearall17 1 QC4.61 [3.09, 7.28]2.79+4.61 [3.09, 7.28]5.66 [3.09, 8.26]12% [0%, 25%]29%41%-0.02+0.282026-08-08 → 2026-08-30
tmin12Znearest30d17 1 QC4.96 [3.55, 6.79]2.83+4.96 [3.55, 6.79]5.98 [4.30, 7.83]12% [0%, 25%]29%35%-0.10+0.272026-08-08 → 2026-08-30
tmin12Znearest90d17 1 QC4.96 [3.23, 7.08]2.83+4.96 [3.23, 7.08]5.98 [3.23, 8.15]12% [0%, 25%]29%35%-0.10+0.272026-08-08 → 2026-08-30
tmin12Znearest365d17 1 QC4.96 [3.23, 7.15]2.83+4.96 [3.23, 7.15]5.98 [3.23, 8.26]12% [0%, 25%]29%35%-0.10+0.272026-08-08 → 2026-08-30
tmin12Znearestall17 1 QC4.96 [3.23, 7.59]2.83+4.96 [3.23, 7.59]5.98 [3.23, 8.59]12% [0%, 25%]29%35%-0.10+0.272026-08-08 → 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 KTTN, lead day 7, 00Z bilinear tmax+10+50-5-102026-08-08: -6.61 °F2026-08-14: +3.78 °F2026-08-15: -1.62 °F2026-08-16: +8.66 °F2026-08-17: -3.2 °F2026-08-18: +3.23 °F2026-08-19: +2.81 °F2026-08-20: +0.08 °F2026-08-21: +2.61 °F2026-08-22: -2.53 °F2026-08-23: -0.58 °F2026-08-24: +0.12 °F2026-08-25: +6.89 °F2026-08-26: -0.92 °F2026-08-27: +0.78 °F2026-08-28: +0.21 °F2026-08-29: +3.84 °F2026-08-30: +0.85 °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+0.85
2026-08-29+3.84
2026-08-28+0.21
2026-08-27+0.78
2026-08-26-0.92
2026-08-25+6.89
2026-08-24+0.12
2026-08-23-0.58
2026-08-22-2.53
2026-08-21+2.61
2026-08-20+0.08
2026-08-19+2.81
2026-08-18+3.23
2026-08-17-3.20
2026-08-16+8.66
2026-08-15-1.62
2026-08-14+3.78
2026-08-13—
2026-08-12—
2026-08-11—
2026-08-10—
2026-08-09—
2026-08-08-6.61

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KTTN, lead day 7-10 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: 0 days-5 to -4 °F: 0 days-4 to -3 °F: 1 day-3 to -2 °F: 1 day-2 to -1 °F: 1 day-1 to 0 °F: 2 days0 to 1 °F: 5 days1 to 2 °F: 0 days2 to 3 °F: 2 days3 to 4 °F: 3 days4 to 5 °F: 0 days5 to 6 °F: 0 days6 to 7 °F: 1 day7 to 8 °F: 0 days8 to 9 °F: 1 day9 to 10 °F: 0 daysdashed: P50 |e| 2.57 · P90 |e| 6.7 °F-100+10 °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
-10.00-9.000
-9.00-8.000
-8.00-7.000
-7.00-6.001
-6.00-5.000
-5.00-4.000
-4.00-3.001
-3.00-2.001
-2.00-1.001
-1.00+0.002
+0.00+1.005
+1.00+2.000
+2.00+3.002
+3.00+4.003
+4.00+5.000
+5.00+6.000
+6.00+7.001
+7.00+8.000
+8.00+9.001
+9.00+10.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08182.74 +1.02

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 +1.22 [0.30, 3.50] yes
NCEP GFS 18 -0.55 [-2.23, 2.74] no
GraphCast (IFS init) 18 +0.19 [-0.55, 2.17] no
Persistence (baseline) 18 -1.31 [-2.47, 2.10] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KTTN (Trenton Mercer), 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/KTTN/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