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

Denver Intl · ECMWF AIFS Single · lead day 2

KDEN · aifs_single · 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, 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
tmax00Zbilinear30d28 1 QC4.01 [3.27, 4.61]2.15-3.59 [-4.40, -2.56]4.49 [3.71, 5.04]4% [0%, 11%]21%39%+0.46+0.712026-08-03 → 2026-08-30
tmax00Zbilinear90d28 1 QC4.01 [3.11, 4.64]2.15-3.59 [-4.46, -2.49]4.49 [3.53, 5.06]4% [0%, 10%]21%39%+0.46+0.712026-08-03 → 2026-08-30
tmax00Zbilinear365d28 1 QC4.01 [3.11, 4.68]2.15-3.59 [-4.44, -2.43]4.49 [3.56, 5.11]4% [0%, 12%]21%39%+0.46+0.712026-08-03 → 2026-08-30
tmax00Zbilinearall28 1 QC4.01 [3.09, 4.66]2.15-3.59 [-4.50, -2.36]4.49 [3.52, 5.11]4% [0%, 12%]21%39%+0.46+0.712026-08-03 → 2026-08-30
tmax00Znearest30d28 1 QC4.10 [3.36, 4.69]2.16-3.65 [-4.50, -2.54]4.56 [3.81, 5.10]4% [0%, 11%]21%36%+0.45+0.712026-08-03 → 2026-08-30
tmax00Znearest90d28 1 QC4.10 [3.25, 4.71]2.16-3.65 [-4.53, -2.48]4.56 [3.67, 5.11]4% [0%, 10%]21%36%+0.45+0.712026-08-03 → 2026-08-30
tmax00Znearest365d28 1 QC4.10 [3.26, 4.77]2.16-3.65 [-4.55, -2.47]4.56 [3.69, 5.16]4% [0%, 12%]21%36%+0.45+0.712026-08-03 → 2026-08-30
tmax00Znearestall28 1 QC4.10 [3.23, 4.75]2.16-3.65 [-4.64, -2.34]4.56 [3.65, 5.15]4% [0%, 12%]21%36%+0.45+0.712026-08-03 → 2026-08-30
tmax12Zbilinear30d28 1 QC3.55 [2.60, 4.39]2.03-3.37 [-4.26, -2.40]4.15 [3.23, 4.87]14% [3%, 29%]36%39%+0.52+0.732026-08-03 → 2026-08-30
tmax12Zbilinear90d28 1 QC3.55 [2.52, 4.39]2.03-3.37 [-4.27, -2.34]4.15 [3.07, 4.88]14% [0%, 30%]36%39%+0.52+0.732026-08-03 → 2026-08-30
tmax12Zbilinear365d28 1 QC3.55 [2.52, 4.44]2.03-3.37 [-4.37, -2.35]4.15 [3.15, 4.95]14% [0%, 31%]36%39%+0.52+0.732026-08-03 → 2026-08-30
tmax12Zbilinearall28 1 QC3.55 [2.46, 4.47]2.03-3.37 [-4.35, -2.27]4.15 [3.09, 4.90]14% [0%, 33%]36%39%+0.52+0.732026-08-03 → 2026-08-30
tmax12Znearest30d28 1 QC3.71 [2.75, 4.55]2.10-3.45 [-4.39, -2.42]4.27 [3.37, 5.00]11% [3%, 19%]29%39%+0.50+0.722026-08-03 → 2026-08-30
tmax12Znearest90d28 1 QC3.71 [2.67, 4.55]2.10-3.45 [-4.40, -2.34]4.27 [3.19, 4.98]11% [0%, 20%]29%39%+0.50+0.722026-08-03 → 2026-08-30
tmax12Znearest365d28 1 QC3.71 [2.68, 4.63]2.10-3.45 [-4.44, -2.38]4.27 [3.27, 5.08]11% [0%, 20%]29%39%+0.50+0.722026-08-03 → 2026-08-30
tmax12Znearestall28 1 QC3.71 [2.57, 4.61]2.10-3.45 [-4.46, -2.29]4.27 [3.22, 5.06]11% [0%, 22%]29%39%+0.50+0.722026-08-03 → 2026-08-30
tmin00Zbilinear30d28 1 QC3.01 [2.10, 4.42]2.32+2.18 [0.80, 4.05]3.75 [2.50, 5.29]18% [4%, 31%]32%61%+0.37+0.522026-08-03 → 2026-08-30
tmin00Zbilinear90d28 1 QC3.01 [2.16, 4.62]2.32+2.18 [0.82, 4.31]3.75 [2.57, 5.64]18% [0%, 32%]32%61%+0.37+0.522026-08-03 → 2026-08-30
tmin00Zbilinear365d28 1 QC3.01 [2.05, 4.41]2.32+2.18 [0.74, 4.20]3.75 [2.43, 5.41]18% [0%, 33%]32%61%+0.37+0.522026-08-03 → 2026-08-30
tmin00Zbilinearall28 1 QC3.01 [2.13, 4.83]2.32+2.18 [0.74, 4.66]3.75 [2.51, 5.71]18% [0%, 33%]32%61%+0.37+0.522026-08-03 → 2026-08-30
tmin00Znearest30d28 1 QC3.06 [2.18, 4.45]2.36+2.21 [0.78, 4.10]3.78 [2.56, 5.30]18% [4%, 31%]36%54%+0.36+0.512026-08-03 → 2026-08-30
tmin00Znearest90d28 1 QC3.06 [2.23, 4.67]2.36+2.21 [0.78, 4.39]3.78 [2.61, 5.64]18% [0%, 32%]36%54%+0.36+0.512026-08-03 → 2026-08-30
tmin00Znearest365d28 1 QC3.06 [2.13, 4.44]2.36+2.21 [0.70, 4.26]3.78 [2.51, 5.43]18% [0%, 33%]36%54%+0.36+0.512026-08-03 → 2026-08-30
tmin00Znearestall28 1 QC3.06 [2.19, 4.88]2.36+2.21 [0.70, 4.69]3.78 [2.54, 5.72]18% [0%, 33%]36%54%+0.36+0.512026-08-03 → 2026-08-30
tmin12Zbilinear30d28 1 QC3.06 [2.18, 4.33]2.26+2.48 [1.11, 4.12]3.84 [2.68, 5.20]25% [12%, 37%]32%54%+0.36+0.532026-08-03 → 2026-08-30
tmin12Zbilinear90d28 1 QC3.06 [2.20, 4.55]2.26+2.48 [1.10, 4.38]3.84 [2.71, 5.50]25% [11%, 37%]32%54%+0.36+0.532026-08-03 → 2026-08-30
tmin12Zbilinear365d28 1 QC3.06 [2.11, 4.38]2.26+2.48 [1.01, 4.28]3.84 [2.58, 5.29]25% [10%, 38%]32%54%+0.36+0.532026-08-03 → 2026-08-30
tmin12Zbilinearall28 1 QC3.06 [2.15, 4.78]2.26+2.48 [1.08, 4.65]3.84 [2.65, 5.60]25% [9%, 38%]32%54%+0.36+0.532026-08-03 → 2026-08-30
tmin12Znearest30d28 1 QC3.12 [2.28, 4.34]2.25+2.51 [1.09, 4.19]3.85 [2.73, 5.18]21% [11%, 33%]32%50%+0.34+0.542026-08-03 → 2026-08-30
tmin12Znearest90d28 1 QC3.12 [2.31, 4.60]2.25+2.51 [1.11, 4.40]3.85 [2.77, 5.46]21% [10%, 32%]32%50%+0.34+0.542026-08-03 → 2026-08-30
tmin12Znearest365d28 1 QC3.12 [2.22, 4.40]2.25+2.51 [1.00, 4.34]3.85 [2.62, 5.29]21% [9%, 33%]32%50%+0.34+0.542026-08-03 → 2026-08-30
tmin12Znearestall28 1 QC3.12 [2.26, 4.78]2.25+2.51 [1.05, 4.71]3.85 [2.69, 5.57]21% [9%, 33%]32%50%+0.34+0.542026-08-03 → 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 AIFS Single at KDEN, lead day 2, 00Z bilinear tmax+10+50-5-102026-08-03: -6.68 °F2026-08-04: +2.96 °F2026-08-05: -1.97 °F2026-08-06: -1.19 °F2026-08-07: -2.19 °F2026-08-08: -4.19 °F2026-08-09: -2.54 °F2026-08-10: -4.16 °F2026-08-11: -5 °F2026-08-12: -7.38 °F2026-08-13: -4.25 °F2026-08-14: -7.01 °F2026-08-15: -3.5 °F2026-08-16: -1.46 °F2026-08-17: -4.99 °F2026-08-18: +2.84 °F2026-08-19: -5.11 °F2026-08-20: -2.68 °F2026-08-21: -7 °F2026-08-22: -7.76 °F2026-08-23: -5.14 °F2026-08-24: -1.51 °F2026-08-25: -0.64 °F2026-08-26: -6.02 °F2026-08-27: -5.67 °F2026-08-28: -3.34 °F2026-08-29: -3.31 °F2026-08-30: -1.66 °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
2026-08-30-1.66
2026-08-29-3.31
2026-08-28-3.34
2026-08-27-5.67
2026-08-26-6.02
2026-08-25-0.64
2026-08-24-1.51
2026-08-23-5.14
2026-08-22-7.76
2026-08-21-7.00
2026-08-20-2.68
2026-08-19-5.11
2026-08-18+2.84
2026-08-17-4.99
2026-08-16-1.46
2026-08-15-3.50
2026-08-14-7.01
2026-08-13-4.25
2026-08-12-7.38
2026-08-11-5.00
2026-08-10-4.16
2026-08-09-2.54
2026-08-08-4.19
2026-08-07-2.19
2026-08-06-1.19
2026-08-05-1.97
2026-08-04+2.96
2026-08-03-6.68

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KDEN, lead day 2-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 3 days-7 to -6 °F: 3 days-6 to -5 °F: 4 days-5 to -4 °F: 4 days-4 to -3 °F: 3 days-3 to -2 °F: 3 days-2 to -1 °F: 5 days-1 to 0 °F: 1 day0 to 1 °F: 0 days1 to 2 °F: 0 days2 to 3 °F: 2 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| 3.83 · P90 |e| 7 °F-100+10 °Fn = 28 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
-8.00-7.003
-7.00-6.003
-6.00-5.004
-5.00-4.004
-4.00-3.003
-3.00-2.003
-2.00-1.005
-1.00+0.001
+0.00+1.000
+1.00+2.000
+2.00+3.002
+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
2026-08284.01 -3.59

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-03 → 2026-08-30 28
ECMWF AIFS Single2026-08-03 → 2026-08-30 28
ECMWF AIFS Single2026-08-03 → 2026-08-30 28
ECMWF AIFS Single2026-08-03 → 2026-08-30 28

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 (IFS init) 1 -1.69 [-1.69, -1.69] yes
FourCastNet v2 (IFS init) 1 -2.42 [-2.42, -2.42] yes
NCEP GFS 28 +0.61 [-0.71, 1.85] no
GraphCast (IFS init) 26 -2.26 [-2.72, -1.68] yes
ECMWF IFS HRES 23 +0.73 [-0.09, 2.18] no
Pangu-Weather (IFS init) 1 +0.96 [0.96, 0.96] yes
Persistence (baseline) 28 -3.42 [-9.24, -0.51] yes

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KDEN (Denver Intl), model aifs_single, 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/KDEN/model/aifs_single/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