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

Denver Intl · ECMWF AIFS Single · lead day 0

KDEN · aifs_single · lead 0

Target day = initialization date + 0 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, aifs-single-gpid5, 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
tmax00Zbilinear30d30 1 QC3.94 [2.75, 4.87]1.87-3.91 [-4.87, -2.67]4.49 [3.33, 5.21]10% [0%, 23%]27%37%——2026-08-01 → 2026-08-30
tmax00Zbilinear90d30 1 QC3.94 [2.49, 4.86]1.87-3.91 [-4.86, -2.42]4.49 [2.98, 5.24]10% [0%, 23%]27%37%——2026-08-01 → 2026-08-30
tmax00Zbilinear365d30 1 QC3.94 [2.53, 4.94]1.87-3.91 [-4.94, -2.46]4.49 [3.03, 5.27]10% [0%, 23%]27%37%——2026-08-01 → 2026-08-30
tmax00Zbilinearall30 1 QC3.94 [2.52, 4.90]1.87-3.91 [-4.90, -2.41]4.49 [3.00, 5.26]10% [0%, 24%]27%37%——2026-08-01 → 2026-08-30
tmax00Znearest30d30 1 QC4.01 [2.78, 4.98]1.85-3.95 [-4.98, -2.60]4.54 [3.35, 5.28]10% [0%, 23%]23%37%——2026-08-01 → 2026-08-30
tmax00Znearest90d30 1 QC4.01 [2.52, 4.96]1.85-3.95 [-4.96, -2.34]4.54 [3.02, 5.32]10% [0%, 23%]23%37%——2026-08-01 → 2026-08-30
tmax00Znearest365d30 1 QC4.01 [2.57, 5.04]1.85-3.95 [-5.04, -2.40]4.54 [3.03, 5.36]10% [0%, 23%]23%37%——2026-08-01 → 2026-08-30
tmax00Znearestall30 1 QC4.01 [2.57, 5.04]1.85-3.95 [-5.04, -2.37]4.54 [3.02, 5.34]10% [0%, 24%]23%37%——2026-08-01 → 2026-08-30
tmin00Zbilinear30d30 1 QC2.49 [1.68, 3.37]2.27+1.45 [0.51, 2.37]3.16 [2.19, 4.06]27% [10%, 43%]50%70%——2026-08-01 → 2026-08-30
tmin00Zbilinear90d30 1 QC2.49 [1.70, 3.49]2.27+1.45 [0.43, 2.54]3.16 [2.24, 4.14]27% [6%, 43%]50%70%——2026-08-01 → 2026-08-30
tmin00Zbilinear365d30 1 QC2.49 [1.65, 3.49]2.27+1.45 [0.29, 2.57]3.16 [2.17, 4.13]27% [0%, 45%]50%70%——2026-08-01 → 2026-08-30
tmin00Zbilinearall30 1 QC2.49 [1.66, 3.61]2.27+1.45 [0.42, 2.46]3.16 [2.20, 4.23]27% [3%, 44%]50%70%——2026-08-01 → 2026-08-30
tmin00Znearest30d30 1 QC2.51 [1.76, 3.36]2.28+1.40 [0.42, 2.34]3.15 [2.23, 4.02]23% [7%, 43%]47%73%——2026-08-01 → 2026-08-30
tmin00Znearest90d30 1 QC2.51 [1.79, 3.46]2.28+1.40 [0.38, 2.51]3.15 [2.32, 4.11]23% [0%, 42%]47%73%——2026-08-01 → 2026-08-30
tmin00Znearest365d30 1 QC2.51 [1.71, 3.50]2.28+1.40 [0.27, 2.53]3.15 [2.18, 4.10]23% [0%, 44%]47%73%——2026-08-01 → 2026-08-30
tmin00Znearestall30 1 QC2.51 [1.76, 3.58]2.28+1.40 [0.36, 2.44]3.15 [2.23, 4.21]23% [0%, 43%]47%73%——2026-08-01 → 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 AIFS Single at KDEN, lead day 0, 00Z bilinear tmax+10+50-5-102026-08-01: -3.84 °F2026-08-02: -1.93 °F2026-08-03: -4.24 °F2026-08-04: +0.46 °F2026-08-05: -0.44 °F2026-08-06: -1.37 °F2026-08-07: -1.69 °F2026-08-08: -4.33 °F2026-08-09: -2.76 °F2026-08-10: -2.25 °F2026-08-11: -3.26 °F2026-08-12: -7.06 °F2026-08-13: -6.01 °F2026-08-14: -7.08 °F2026-08-15: -4.71 °F2026-08-16: -4.5 °F2026-08-17: -4.33 °F2026-08-18: -5.32 °F2026-08-19: -4.56 °F2026-08-20: -0.4 °F2026-08-21: -7.84 °F2026-08-22: -6.16 °F2026-08-23: -4.67 °F2026-08-24: -1.34 °F2026-08-25: -2.25 °F2026-08-26: -6.05 °F2026-08-27: -7.21 °F2026-08-28: -4.68 °F2026-08-29: -5.85 °F2026-08-30: -1.71 °F2026-08-012026-08-30°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 (30 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-1.71
2026-08-29-5.85
2026-08-28-4.68
2026-08-27-7.21
2026-08-26-6.05
2026-08-25-2.25
2026-08-24-1.34
2026-08-23-4.67
2026-08-22-6.16
2026-08-21-7.84
2026-08-20-0.40
2026-08-19-4.56
2026-08-18-5.32
2026-08-17-4.33
2026-08-16-4.50
2026-08-15-4.71
2026-08-14-7.08
2026-08-13-6.01
2026-08-12-7.06
2026-08-11-3.26
2026-08-10-2.25
2026-08-09-2.76
2026-08-08-4.33
2026-08-07-1.69
2026-08-06-1.37
2026-08-05-0.44
2026-08-04+0.46
2026-08-03-4.24
2026-08-02-1.93
2026-08-01-3.84

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KDEN, lead day 0-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 4 days-7 to -6 °F: 3 days-6 to -5 °F: 2 days-5 to -4 °F: 8 days-4 to -3 °F: 2 days-3 to -2 °F: 3 days-2 to -1 °F: 5 days-1 to 0 °F: 2 days0 to 1 °F: 1 day1 to 2 °F: 0 days2 to 3 °F: 0 days3 to 4 °F: 0 days4 to 5 °F: 0 days5 to 6 °F: 0 days6 to 7 °F: 0 days7 to 8 °F: 0 days8 to 9 °F: 0 days9 to 10 °F: 0 daysdashed: P50 |e| 4.33 · P90 |e| 7.06 °F-100+10 °Fn = 30 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
-8.00-7.004
-7.00-6.003
-6.00-5.002
-5.00-4.008
-4.00-3.002
-3.00-2.003
-2.00-1.005
-1.00+0.002
+0.00+1.001
+1.00+2.000
+2.00+3.000
+3.00+4.000
+4.00+5.000
+5.00+6.000
+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
2026-08303.94 -3.91

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-01 → 2026-08-30 30
ECMWF AIFS Single2026-08-01 → 2026-08-30 30

Compared with other models

Paired bootstrap on the days both models cover (90d, 00Z, bilinear, daily maximum). Negative means ECMWF AIFS Single has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
Aurora (GFS init) 2 -2.31 [-3.25, -1.37] yes
Aurora (IFS init) 3 -0.71 [-0.90, -0.35] yes
FourCastNet v2 (GFS init) 2 -3.61 [-4.20, -3.02] yes
FourCastNet v2 (IFS init) 3 -1.43 [-2.22, -0.97] yes
NCEP GFS 30 +0.22 [-0.87, 1.32] no
GraphCast (GFS init) 2 -1.50 [-1.61, -1.38] yes
GraphCast (IFS init) 28 -1.78 [-2.30, -1.34] yes
ECMWF IFS HRES 25 +0.94 [-0.03, 1.62] no
Pangu-Weather (GFS init) 2 -0.36 [-0.91, 0.19] no
Pangu-Weather (IFS init) 3 +1.78 [1.29, 2.02] yes

Cite this page

ShortCastCheck, KDEN aifs_single lead 0, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KDEN/model/aifs_single/lead/0/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KDEN (Denver Intl), model aifs_single, lead day 0. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KDEN/model/aifs_single/lead/0/

Accessed2026-08-31 (data through 2026-08-30; page built 2026-08-31T03:52:06+00:00)

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