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

Denver Intl · ECMWF AIFS Single · lead day 1

KDEN · aifs_single · lead 1

Target day = initialization date + 1 day. 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
tmax00Zbilinear30d29 1 QC3.92 [2.97, 4.65]1.81-3.77 [-4.64, -2.50]4.37 [3.43, 4.98]3% [0%, 11%]24%38%+0.31+0.682026-08-02 → 2026-08-30
tmax00Zbilinear90d29 1 QC3.92 [2.84, 4.66]1.81-3.77 [-4.64, -2.38]4.37 [3.27, 4.99]3% [0%, 12%]24%38%+0.31+0.682026-08-02 → 2026-08-30
tmax00Zbilinear365d29 1 QC3.92 [2.88, 4.69]1.81-3.77 [-4.69, -2.39]4.37 [3.35, 5.01]3% [0%, 12%]24%38%+0.31+0.682026-08-02 → 2026-08-30
tmax00Zbilinearall29 1 QC3.92 [2.85, 4.77]1.81-3.77 [-4.77, -2.39]4.37 [3.32, 5.07]3% [0%, 12%]24%38%+0.31+0.682026-08-02 → 2026-08-30
tmax00Znearest30d29 1 QC4.04 [3.12, 4.76]1.84-3.83 [-4.74, -2.50]4.46 [3.57, 5.08]3% [0%, 11%]17%38%+0.29+0.682026-08-02 → 2026-08-30
tmax00Znearest90d29 1 QC4.04 [2.99, 4.77]1.84-3.83 [-4.76, -2.34]4.46 [3.39, 5.08]3% [0%, 12%]17%38%+0.29+0.682026-08-02 → 2026-08-30
tmax00Znearest365d29 1 QC4.04 [3.05, 4.84]1.84-3.83 [-4.84, -2.39]4.46 [3.47, 5.14]3% [0%, 12%]17%38%+0.29+0.682026-08-02 → 2026-08-30
tmax00Znearestall29 1 QC4.04 [3.03, 4.87]1.84-3.83 [-4.87, -2.34]4.46 [3.43, 5.19]3% [0%, 12%]17%38%+0.29+0.682026-08-02 → 2026-08-30
tmax12Zbilinear30d29 1 QC3.68 [2.77, 4.44]1.87-3.47 [-4.43, -2.13]4.15 [3.18, 4.83]3% [0%, 10%]28%41%+0.35+0.672026-08-02 → 2026-08-30
tmax12Zbilinear90d29 1 QC3.68 [2.63, 4.48]1.87-3.47 [-4.47, -1.97]4.15 [3.01, 4.85]3% [0%, 10%]28%41%+0.35+0.672026-08-02 → 2026-08-30
tmax12Zbilinear365d29 1 QC3.68 [2.66, 4.52]1.87-3.47 [-4.52, -1.98]4.15 [3.05, 4.86]3% [0%, 11%]28%41%+0.35+0.672026-08-02 → 2026-08-30
tmax12Zbilinearall29 1 QC3.68 [2.63, 4.59]1.87-3.47 [-4.58, -1.98]4.15 [3.04, 4.91]3% [0%, 12%]28%41%+0.35+0.672026-08-02 → 2026-08-30
tmax12Znearest30d29 1 QC3.79 [2.96, 4.54]1.88-3.52 [-4.52, -2.14]4.23 [3.32, 4.91]3% [0%, 10%]24%38%+0.33+0.672026-08-02 → 2026-08-30
tmax12Znearest90d29 1 QC3.79 [2.80, 4.57]1.88-3.52 [-4.55, -1.96]4.23 [3.12, 4.92]3% [0%, 10%]24%38%+0.33+0.672026-08-02 → 2026-08-30
tmax12Znearest365d29 1 QC3.79 [2.81, 4.64]1.88-3.52 [-4.64, -1.98]4.23 [3.18, 4.99]3% [0%, 11%]24%38%+0.33+0.672026-08-02 → 2026-08-30
tmax12Znearestall29 1 QC3.79 [2.79, 4.70]1.88-3.52 [-4.70, -1.95]4.23 [3.16, 5.00]3% [0%, 12%]24%38%+0.33+0.672026-08-02 → 2026-08-30
tmin00Zbilinear30d29 1 QC3.02 [2.13, 4.22]2.49+2.01 [0.99, 3.14]3.75 [2.59, 5.00]21% [11%, 30%]38%59%+0.26+0.392026-08-02 → 2026-08-30
tmin00Zbilinear90d29 1 QC3.02 [2.20, 4.42]2.49+2.01 [0.92, 3.21]3.75 [2.65, 5.28]21% [10%, 29%]38%59%+0.26+0.392026-08-02 → 2026-08-30
tmin00Zbilinear365d29 1 QC3.02 [2.11, 4.40]2.49+2.01 [0.84, 3.24]3.75 [2.56, 5.11]21% [10%, 29%]38%59%+0.26+0.392026-08-02 → 2026-08-30
tmin00Zbilinearall29 1 QC3.02 [2.10, 4.77]2.49+2.01 [0.87, 3.25]3.75 [2.57, 5.43]21% [8%, 29%]38%59%+0.26+0.392026-08-02 → 2026-08-30
tmin00Znearest30d29 1 QC3.05 [2.18, 4.22]2.46+2.05 [0.97, 3.16]3.74 [2.59, 4.95]21% [11%, 30%]38%59%+0.26+0.402026-08-02 → 2026-08-30
tmin00Znearest90d29 1 QC3.05 [2.24, 4.45]2.46+2.05 [0.93, 3.25]3.74 [2.64, 5.25]21% [10%, 29%]38%59%+0.26+0.402026-08-02 → 2026-08-30
tmin00Znearest365d29 1 QC3.05 [2.15, 4.37]2.46+2.05 [0.82, 3.30]3.74 [2.57, 5.07]21% [10%, 29%]38%59%+0.26+0.402026-08-02 → 2026-08-30
tmin00Znearestall29 1 QC3.05 [2.16, 4.74]2.46+2.05 [0.85, 3.33]3.74 [2.55, 5.41]21% [8%, 29%]38%59%+0.26+0.402026-08-02 → 2026-08-30
tmin12Zbilinear30d29 1 QC3.08 [2.09, 4.19]2.55+2.12 [1.01, 3.27]3.80 [2.64, 4.84]24% [11%, 37%]34%55%+0.25+0.382026-08-02 → 2026-08-30
tmin12Zbilinear90d29 1 QC3.08 [2.17, 4.45]2.55+2.12 [0.97, 3.45]3.80 [2.77, 4.96]24% [10%, 35%]34%55%+0.25+0.382026-08-02 → 2026-08-30
tmin12Zbilinear365d29 1 QC3.08 [2.10, 4.38]2.55+2.12 [0.85, 3.48]3.80 [2.61, 5.00]24% [10%, 36%]34%55%+0.25+0.382026-08-02 → 2026-08-30
tmin12Zbilinearall29 1 QC3.08 [2.09, 4.72]2.55+2.12 [0.90, 3.46]3.80 [2.63, 5.26]24% [8%, 38%]34%55%+0.25+0.382026-08-02 → 2026-08-30
tmin12Znearest30d29 1 QC3.10 [2.12, 4.22]2.53+2.17 [1.00, 3.32]3.80 [2.67, 4.83]24% [11%, 40%]38%52%+0.25+0.382026-08-02 → 2026-08-30
tmin12Znearest90d29 1 QC3.10 [2.20, 4.42]2.53+2.17 [0.97, 3.50]3.80 [2.76, 4.97]24% [9%, 40%]38%52%+0.25+0.382026-08-02 → 2026-08-30
tmin12Znearest365d29 1 QC3.10 [2.11, 4.42]2.53+2.17 [0.88, 3.51]3.80 [2.61, 5.02]24% [8%, 43%]38%52%+0.25+0.382026-08-02 → 2026-08-30
tmin12Znearestall29 1 QC3.10 [2.10, 4.74]2.53+2.17 [0.90, 3.48]3.80 [2.64, 5.25]24% [8%, 41%]38%52%+0.25+0.382026-08-02 → 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 1, 00Z bilinear tmax+10+50-5-102026-08-02: -3.36 °F2026-08-03: -5.33 °F2026-08-04: +1.84 °F2026-08-05: +0.41 °F2026-08-06: -1.55 °F2026-08-07: -1.5 °F2026-08-08: -3.72 °F2026-08-09: -2.75 °F2026-08-10: -3.57 °F2026-08-11: -4.19 °F2026-08-12: -6.9 °F2026-08-13: -4.12 °F2026-08-14: -8.33 °F2026-08-15: -4.42 °F2026-08-16: -2.41 °F2026-08-17: -4.86 °F2026-08-18: -2.63 °F2026-08-19: -4.97 °F2026-08-20: -1.32 °F2026-08-21: -6 °F2026-08-22: -4.74 °F2026-08-23: -5.87 °F2026-08-24: -1.87 °F2026-08-25: -1.45 °F2026-08-26: -5.87 °F2026-08-27: -5.7 °F2026-08-28: -5.95 °F2026-08-29: -5.48 °F2026-08-30: -2.58 °F2026-08-022026-08-30°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 (29 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-2.58
2026-08-29-5.48
2026-08-28-5.95
2026-08-27-5.70
2026-08-26-5.87
2026-08-25-1.45
2026-08-24-1.87
2026-08-23-5.87
2026-08-22-4.74
2026-08-21-6.00
2026-08-20-1.32
2026-08-19-4.97
2026-08-18-2.63
2026-08-17-4.86
2026-08-16-2.41
2026-08-15-4.42
2026-08-14-8.33
2026-08-13-4.12
2026-08-12-6.90
2026-08-11-4.19
2026-08-10-3.57
2026-08-09-2.75
2026-08-08-3.72
2026-08-07-1.50
2026-08-06-1.55
2026-08-05+0.41
2026-08-04+1.84
2026-08-03-5.33
2026-08-02-3.36

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KDEN, lead day 1-10 to -9 °F: 0 days-9 to -8 °F: 1 day-8 to -7 °F: 0 days-7 to -6 °F: 2 days-6 to -5 °F: 6 days-5 to -4 °F: 6 days-4 to -3 °F: 3 days-3 to -2 °F: 4 days-2 to -1 °F: 5 days-1 to 0 °F: 0 days0 to 1 °F: 1 day1 to 2 °F: 1 day2 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| 4.12 · P90 |e| 5.96 °F-100+10 °Fn = 29 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
-9.00-8.001
-8.00-7.000
-7.00-6.002
-6.00-5.006
-5.00-4.006
-4.00-3.003
-3.00-2.004
-2.00-1.005
-1.00+0.000
+0.00+1.001
+1.00+2.001
+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
2026-08293.92 -3.77

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-02 → 2026-08-30 29
ECMWF AIFS Single2026-08-02 → 2026-08-30 29
ECMWF AIFS Single2026-08-02 → 2026-08-30 29
ECMWF AIFS Single2026-08-02 → 2026-08-30 29

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) 1 -2.43 [-2.43, -2.43] yes
Aurora (IFS init) 2 -0.99 [-1.05, -0.93] yes
FourCastNet v2 (GFS init) 1 -1.57 [-1.57, -1.57] yes
FourCastNet v2 (IFS init) 2 -1.52 [-1.70, -1.35] yes
NCEP GFS 29 +0.07 [-0.96, 1.22] no
GraphCast (GFS init) 1 -0.48 [-0.48, -0.48] yes
GraphCast (IFS init) 27 -2.14 [-2.59, -1.52] yes
ECMWF IFS HRES 22 +0.63 [-0.42, 1.62] no
Pangu-Weather (GFS init) 1 +2.32 [2.32, 2.32] yes
Pangu-Weather (IFS init) 2 +2.23 [2.08, 2.38] yes
Persistence (baseline) 29 -1.77 [-5.34, 0.31] no

Cite this page

ShortCastCheck, KDEN aifs_single lead 1, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KDEN/model/aifs_single/lead/1/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KDEN (Denver Intl), model aifs_single, lead day 1. 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/1/

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

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