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

Denver Intl · ECMWF IFS HRES · lead day 8

KDEN · ifs_hres · lead 8

Target day = initialization date + 8 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
tmax00Zbilinear30d17 1 QC6.03 [4.26, 8.03]5.20-3.91 [-6.93, 1.38]7.70 [5.98, 9.15]12% [0%, 21%]35%41%+0.17+0.272026-08-09 → 2026-08-30
tmax00Zbilinear90d17 1 QC6.03 [4.07, 8.38]5.20-3.91 [-7.09, 4.14]7.70 [5.32, 9.40]12% [0%, 25%]35%41%+0.17+0.272026-08-09 → 2026-08-30
tmax00Zbilinear365d17 1 QC6.03 [3.96, 8.32]5.20-3.91 [-7.41, 4.14]7.70 [5.07, 9.39]12% [0%, 25%]35%41%+0.17+0.272026-08-09 → 2026-08-30
tmax00Zbilinearall17 1 QC6.03 [4.06, 8.50]5.20-3.91 [-7.41, 4.14]7.70 [5.23, 9.48]12% [0%, 23%]35%41%+0.17+0.272026-08-09 → 2026-08-30
tmax00Znearest30d17 1 QC6.27 [4.28, 8.40]5.36-4.24 [-7.37, 1.28]8.15 [6.13, 9.66]12% [0%, 24%]29%35%+0.14+0.242026-08-09 → 2026-08-30
tmax00Znearest90d17 1 QC6.27 [3.58, 8.66]5.36-4.24 [-7.48, 3.49]8.15 [5.30, 9.89]12% [0%, 24%]29%35%+0.14+0.242026-08-09 → 2026-08-30
tmax00Znearest365d17 1 QC6.27 [3.51, 8.53]5.36-4.24 [-7.82, 3.49]8.15 [5.29, 9.86]12% [0%, 25%]29%35%+0.14+0.242026-08-09 → 2026-08-30
tmax00Znearestall17 1 QC6.27 [3.56, 8.79]5.36-4.24 [-7.82, 3.49]8.15 [5.40, 9.95]12% [0%, 25%]29%35%+0.14+0.242026-08-09 → 2026-08-30
tmax12Zbilinear30d17 1 QC6.42 [4.58, 7.68]4.51-5.30 [-7.44, -0.60]7.84 [5.50, 9.48]12% [0%, 23%]12%18%+0.12+0.362026-08-09 → 2026-08-30
tmax12Zbilinear90d17 1 QC6.42 [3.78, 7.74]4.51-5.30 [-7.51, 3.17]7.84 [3.78, 9.60]12% [0%, 25%]12%18%+0.12+0.362026-08-09 → 2026-08-30
tmax12Zbilinear365d17 1 QC6.42 [3.78, 7.85]4.51-5.30 [-7.81, 3.78]7.84 [3.78, 9.73]12% [0%, 25%]12%18%+0.12+0.362026-08-09 → 2026-08-30
tmax12Zbilinearall17 1 QC6.42 [3.78, 7.74]4.51-5.30 [-7.63, 3.56]7.84 [3.83, 9.69]12% [0%, 25%]12%18%+0.12+0.362026-08-09 → 2026-08-30
tmax12Znearest30d17 1 QC6.68 [4.82, 8.05]4.53-5.52 [-7.77, -0.66]8.02 [5.62, 9.69]0% [0%, 0%]12%24%+0.08+0.362026-08-09 → 2026-08-30
tmax12Znearest90d17 1 QC6.68 [3.53, 8.20]4.53-5.52 [-7.85, 3.27]8.02 [3.71, 9.85]0% [0%, 0%]12%24%+0.08+0.362026-08-09 → 2026-08-30
tmax12Znearest365d17 1 QC6.68 [3.29, 8.30]4.53-5.52 [-8.28, 3.29]8.02 [3.70, 9.97]0% [0%, 0%]12%24%+0.08+0.362026-08-09 → 2026-08-30
tmax12Znearestall17 1 QC6.68 [3.67, 8.20]4.53-5.52 [-8.04, 3.29]8.02 [3.79, 9.91]0% [0%, 0%]12%24%+0.08+0.362026-08-09 → 2026-08-30
tmin00Zbilinear30d17 1 QC3.50 [2.49, 5.13]2.54+3.16 [1.93, 5.13]4.41 [3.10, 6.09]12% [0%, 25%]35%53%+0.27+0.432026-08-09 → 2026-08-30
tmin00Zbilinear90d17 1 QC3.50 [2.38, 5.61]2.54+3.16 [1.90, 5.61]4.41 [2.69, 6.49]12% [0%, 27%]35%53%+0.27+0.432026-08-09 → 2026-08-30
tmin00Zbilinear365d17 1 QC3.50 [2.27, 5.53]2.54+3.16 [1.84, 5.53]4.41 [2.54, 6.37]12% [0%, 29%]35%53%+0.27+0.432026-08-09 → 2026-08-30
tmin00Zbilinearall17 1 QC3.50 [2.33, 5.64]2.54+3.16 [1.89, 5.64]4.41 [2.66, 6.71]12% [0%, 29%]35%53%+0.27+0.432026-08-09 → 2026-08-30
tmin00Znearest30d17 1 QC3.35 [2.29, 4.97]2.55+2.95 [1.63, 4.97]4.23 [2.81, 5.84]18% [0%, 29%]47%53%+0.31+0.432026-08-09 → 2026-08-30
tmin00Znearest90d17 1 QC3.35 [2.25, 5.38]2.55+2.95 [1.56, 5.38]4.23 [2.40, 6.21]18% [0%, 30%]47%53%+0.31+0.432026-08-09 → 2026-08-30
tmin00Znearest365d17 1 QC3.35 [2.20, 5.34]2.55+2.95 [1.45, 5.34]4.23 [2.25, 6.11]18% [0%, 29%]47%53%+0.31+0.432026-08-09 → 2026-08-30
tmin00Znearestall17 1 QC3.35 [2.20, 5.48]2.55+2.95 [1.53, 5.48]4.23 [2.29, 6.37]18% [0%, 30%]47%53%+0.31+0.432026-08-09 → 2026-08-30
tmin12Zbilinear30d17 1 QC3.06 [2.06, 4.70]1.96+2.81 [1.81, 4.67]3.93 [2.42, 5.64]24% [8%, 40%]35%53%+0.37+0.562026-08-09 → 2026-08-30
tmin12Zbilinear90d17 1 QC3.06 [2.04, 4.98]1.96+2.81 [1.80, 4.98]3.93 [2.41, 6.02]24% [0%, 40%]35%53%+0.37+0.562026-08-09 → 2026-08-30
tmin12Zbilinear365d17 1 QC3.06 [2.04, 4.85]1.96+2.81 [1.72, 4.85]3.93 [2.39, 6.06]24% [0%, 43%]35%53%+0.37+0.562026-08-09 → 2026-08-30
tmin12Zbilinearall17 1 QC3.06 [2.00, 4.83]1.96+2.81 [1.79, 4.83]3.93 [2.37, 6.01]24% [0%, 42%]35%53%+0.37+0.562026-08-09 → 2026-08-30
tmin12Znearest30d17 1 QC3.03 [1.94, 4.70]2.16+2.67 [1.59, 4.57]3.90 [2.27, 5.61]18% [8%, 28%]53%59%+0.37+0.522026-08-09 → 2026-08-30
tmin12Znearest90d17 1 QC3.03 [1.86, 5.17]2.16+2.67 [1.56, 5.17]3.90 [2.18, 6.01]18% [0%, 29%]53%59%+0.37+0.522026-08-09 → 2026-08-30
tmin12Znearest365d17 1 QC3.03 [1.87, 5.17]2.16+2.67 [1.53, 5.17]3.90 [2.17, 5.97]18% [0%, 29%]53%59%+0.37+0.522026-08-09 → 2026-08-30
tmin12Znearestall17 1 QC3.03 [1.80, 5.17]2.16+2.67 [1.56, 5.17]3.90 [2.03, 5.98]18% [0%, 29%]53%59%+0.37+0.522026-08-09 → 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 KDEN, lead day 8, 00Z bilinear tmax+20+100-10-202026-08-09: +4.14 °F2026-08-15: -8.35 °F2026-08-16: -7.29 °F2026-08-17: -12.12 °F2026-08-18: -2.92 °F2026-08-19: -3.73 °F2026-08-20: -12.81 °F2026-08-21: -12.4 °F2026-08-22: -0.59 °F2026-08-23: -1.61 °F2026-08-24: -4.92 °F2026-08-25: +1.28 °F2026-08-26: -1.99 °F2026-08-27: -1.37 °F2026-08-28: -13.65 °F2026-08-29: -0.67 °F2026-08-30: +12.59 °F2026-08-092026-08-30°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 (22 days, newest first) · download CSV
Climatological dayError °F
2026-08-30+12.59
2026-08-29-0.67
2026-08-28-13.65
2026-08-27-1.37
2026-08-26-1.99
2026-08-25+1.28
2026-08-24-4.92
2026-08-23-1.61
2026-08-22-0.59
2026-08-21-12.40
2026-08-20-12.81
2026-08-19-3.73
2026-08-18-2.92
2026-08-17-12.12
2026-08-16-7.29
2026-08-15-8.35
2026-08-14—
2026-08-13—
2026-08-12—
2026-08-11—
2026-08-10—
2026-08-09+4.14

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KDEN, lead day 8-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 4 days-12 to -10 °F: 0 days-10 to -8 °F: 1 day-8 to -6 °F: 1 day-6 to -4 °F: 1 day-4 to -2 °F: 2 days-2 to 0 °F: 5 days0 to 2 °F: 1 day2 to 4 °F: 0 days4 to 6 °F: 1 day6 to 8 °F: 0 days8 to 10 °F: 0 days10 to 12 °F: 0 days12 to 14 °F: 1 day14 to 16 °F: 0 days16 to 18 °F: 0 days18 to 20 °F: 0 daysdashed: P50 |e| 4.14 · P90 |e| 12.67 °F-200+20 °Fn = 17 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
-14.00-12.004
-12.00-10.000
-10.00-8.001
-8.00-6.001
-6.00-4.001
-4.00-2.002
-2.00+0.005
+0.00+2.001
+2.00+4.000
+4.00+6.001
+6.00+8.000
+8.00+10.000
+10.00+12.000
+12.00+14.001
+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
2026-08176.03 -3.91

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-09 → 2026-08-30 17
ECMWF IFS HRES2026-08-09 → 2026-08-30 17
ECMWF IFS HRES2026-08-09 → 2026-08-30 17
ECMWF IFS HRES2026-08-09 → 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 17 +1.87 [0.33, 4.28] yes
NCEP GFS 17 +1.46 [-0.70, 4.63] no
GraphCast (IFS init) 17 -3.04 [-6.17, 0.73] no
Persistence (baseline) 17 -1.27 [-3.25, 2.26] no

Cite this page

ShortCastCheck, KDEN ifs_hres lead 8, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KDEN/model/ifs_hres/lead/8/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KDEN (Denver Intl), model ifs_hres, lead day 8. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KDEN/model/ifs_hres/lead/8/

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