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

Denver Intl · ECMWF AIFS Single · lead day 7

KDEN · aifs_single · 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, 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
tmax00Zbilinear30d23 1 QC6.66 [4.43, 8.36]4.43-6.37 [-8.18, -4.06]8.39 [5.56, 9.93]22% [5%, 39%]30%35%+0.19+0.452026-08-08 → 2026-08-30
tmax00Zbilinear90d23 1 QC6.66 [4.10, 8.47]4.43-6.37 [-8.18, -3.58]8.39 [4.94, 9.99]22% [0%, 41%]30%35%+0.19+0.452026-08-08 → 2026-08-30
tmax00Zbilinear365d23 1 QC6.66 [3.87, 8.53]4.43-6.37 [-8.34, -3.42]8.39 [4.85, 10.11]22% [0%, 43%]30%35%+0.19+0.452026-08-08 → 2026-08-30
tmax00Zbilinearall23 1 QC6.66 [4.08, 8.54]4.43-6.37 [-8.30, -3.52]8.39 [4.87, 10.07]22% [0%, 43%]30%35%+0.19+0.452026-08-08 → 2026-08-30
tmax00Znearest30d23 1 QC6.67 [4.43, 8.41]4.39-6.46 [-8.24, -4.17]8.44 [5.59, 10.04]17% [0%, 38%]30%30%+0.19+0.462026-08-08 → 2026-08-30
tmax00Znearest90d23 1 QC6.67 [4.07, 8.51]4.39-6.46 [-8.33, -3.70]8.44 [4.93, 10.11]17% [0%, 41%]30%30%+0.19+0.462026-08-08 → 2026-08-30
tmax00Znearest365d23 1 QC6.67 [3.83, 8.58]4.39-6.46 [-8.42, -3.53]8.44 [4.84, 10.22]17% [0%, 43%]30%30%+0.19+0.462026-08-08 → 2026-08-30
tmax00Znearestall23 1 QC6.67 [4.02, 8.57]4.39-6.46 [-8.40, -3.64]8.44 [4.84, 10.20]17% [0%, 43%]30%30%+0.19+0.462026-08-08 → 2026-08-30
tmax12Zbilinear30d23 1 QC6.51 [4.22, 8.77]4.11-6.39 [-8.49, -4.16]8.00 [5.08, 10.10]4% [0%, 13%]26%30%+0.21+0.492026-08-08 → 2026-08-30
tmax12Zbilinear90d23 1 QC6.51 [4.00, 8.80]4.11-6.39 [-8.59, -3.99]8.00 [4.64, 10.15]4% [0%, 13%]26%30%+0.21+0.492026-08-08 → 2026-08-30
tmax12Zbilinear365d23 1 QC6.51 [3.99, 8.93]4.11-6.39 [-8.70, -3.99]8.00 [4.67, 10.35]4% [0%, 14%]26%30%+0.21+0.492026-08-08 → 2026-08-30
tmax12Zbilinearall23 1 QC6.51 [3.86, 9.02]4.11-6.39 [-8.80, -3.85]8.00 [4.58, 10.36]4% [0%, 14%]26%30%+0.21+0.492026-08-08 → 2026-08-30
tmax12Znearest30d23 1 QC6.55 [4.19, 8.87]4.16-6.45 [-8.66, -4.15]8.08 [5.09, 10.24]4% [0%, 13%]22%30%+0.21+0.492026-08-08 → 2026-08-30
tmax12Znearest90d23 1 QC6.55 [4.03, 8.95]4.16-6.45 [-8.75, -4.02]8.08 [4.65, 10.31]4% [0%, 13%]22%30%+0.21+0.492026-08-08 → 2026-08-30
tmax12Znearest365d23 1 QC6.55 [3.99, 9.05]4.16-6.45 [-8.89, -3.97]8.08 [4.68, 10.45]4% [0%, 14%]22%30%+0.21+0.492026-08-08 → 2026-08-30
tmax12Znearestall23 1 QC6.55 [3.88, 9.17]4.16-6.45 [-8.99, -3.87]8.08 [4.57, 10.52]4% [0%, 14%]22%30%+0.21+0.492026-08-08 → 2026-08-30
tmin00Zbilinear30d23 1 QC3.21 [2.51, 3.88]3.17+0.86 [-0.71, 2.99]3.85 [3.11, 4.43]13% [0%, 24%]35%57%+0.43+0.442026-08-08 → 2026-08-30
tmin00Zbilinear90d23 1 QC3.21 [2.40, 3.92]3.17+0.86 [-0.91, 3.36]3.85 [2.97, 4.41]13% [0%, 24%]35%57%+0.43+0.442026-08-08 → 2026-08-30
tmin00Zbilinear365d23 1 QC3.21 [2.40, 3.99]3.17+0.86 [-0.89, 3.73]3.85 [2.92, 4.45]13% [0%, 24%]35%57%+0.43+0.442026-08-08 → 2026-08-30
tmin00Zbilinearall23 1 QC3.21 [2.31, 3.93]3.17+0.86 [-0.92, 3.51]3.85 [2.83, 4.41]13% [0%, 25%]35%57%+0.43+0.442026-08-08 → 2026-08-30
tmin00Znearest30d23 1 QC3.26 [2.52, 3.96]3.23+0.88 [-0.71, 3.09]3.91 [3.12, 4.51]13% [0%, 24%]35%61%+0.42+0.432026-08-08 → 2026-08-30
tmin00Znearest90d23 1 QC3.26 [2.40, 4.01]3.23+0.88 [-0.87, 3.50]3.91 [2.97, 4.52]13% [0%, 24%]35%61%+0.42+0.432026-08-08 → 2026-08-30
tmin00Znearest365d23 1 QC3.26 [2.40, 4.07]3.23+0.88 [-0.88, 3.82]3.91 [2.91, 4.54]13% [0%, 24%]35%61%+0.42+0.432026-08-08 → 2026-08-30
tmin00Znearestall23 1 QC3.26 [2.33, 4.01]3.23+0.88 [-0.86, 3.61]3.91 [2.85, 4.51]13% [0%, 25%]35%61%+0.42+0.432026-08-08 → 2026-08-30
tmin12Zbilinear30d23 1 QC2.62 [2.15, 3.34]2.36+1.24 [-0.73, 2.94]3.08 [2.63, 3.65]22% [6%, 33%]35%52%+0.53+0.582026-08-08 → 2026-08-30
tmin12Zbilinear90d23 1 QC2.62 [2.16, 3.49]2.36+1.24 [-1.28, 3.08]3.08 [2.63, 3.72]22% [0%, 34%]35%52%+0.53+0.582026-08-08 → 2026-08-30
tmin12Zbilinear365d23 1 QC2.62 [2.12, 3.57]2.36+1.24 [-1.23, 3.38]3.08 [2.57, 3.74]22% [0%, 36%]35%52%+0.53+0.582026-08-08 → 2026-08-30
tmin12Zbilinearall23 1 QC2.62 [2.14, 3.59]2.36+1.24 [-1.31, 3.44]3.08 [2.62, 3.81]22% [0%, 36%]35%52%+0.53+0.582026-08-08 → 2026-08-30
tmin12Znearest30d23 1 QC2.69 [2.22, 3.39]2.44+1.29 [-0.77, 3.06]3.18 [2.70, 3.74]22% [6%, 33%]39%52%+0.52+0.572026-08-08 → 2026-08-30
tmin12Znearest90d23 1 QC2.69 [2.24, 3.55]2.44+1.29 [-1.28, 3.20]3.18 [2.71, 3.80]22% [0%, 34%]39%52%+0.52+0.572026-08-08 → 2026-08-30
tmin12Znearest365d23 1 QC2.69 [2.19, 3.62]2.44+1.29 [-1.31, 3.45]3.18 [2.67, 3.83]22% [0%, 36%]39%52%+0.52+0.572026-08-08 → 2026-08-30
tmin12Znearestall23 1 QC2.69 [2.22, 3.70]2.44+1.29 [-1.38, 3.52]3.18 [2.70, 3.91]22% [0%, 36%]39%52%+0.52+0.572026-08-08 → 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 AIFS Single at KDEN, lead day 7, 00Z bilinear tmax+20+100-10-202026-08-08: -6.51 °F2026-08-09: -6.38 °F2026-08-10: +1.68 °F2026-08-11: -14.73 °F2026-08-12: -10.87 °F2026-08-13: -2.99 °F2026-08-14: -17.35 °F2026-08-15: -8.23 °F2026-08-16: -0.92 °F2026-08-17: -7.7 °F2026-08-18: -1.77 °F2026-08-19: -12.11 °F2026-08-20: -13.48 °F2026-08-21: -15.06 °F2026-08-22: -0.66 °F2026-08-23: -7.58 °F2026-08-24: -4.05 °F2026-08-25: -0.12 °F2026-08-26: +0.86 °F2026-08-27: -7.45 °F2026-08-28: -5.63 °F2026-08-29: +0.72 °F2026-08-30: -6.23 °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
2026-08-30-6.23
2026-08-29+0.72
2026-08-28-5.63
2026-08-27-7.45
2026-08-26+0.86
2026-08-25-0.12
2026-08-24-4.05
2026-08-23-7.58
2026-08-22-0.66
2026-08-21-15.06
2026-08-20-13.48
2026-08-19-12.11
2026-08-18-1.77
2026-08-17-7.70
2026-08-16-0.92
2026-08-15-8.23
2026-08-14-17.35
2026-08-13-2.99
2026-08-12-10.87
2026-08-11-14.73
2026-08-10+1.68
2026-08-09-6.38
2026-08-08-6.51

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KDEN, lead day 7-20 to -18 °F: 0 days-18 to -16 °F: 1 day-16 to -14 °F: 2 days-14 to -12 °F: 2 days-12 to -10 °F: 1 day-10 to -8 °F: 1 day-8 to -6 °F: 6 days-6 to -4 °F: 2 days-4 to -2 °F: 1 day-2 to 0 °F: 4 days0 to 2 °F: 3 days2 to 4 °F: 0 days4 to 6 °F: 0 days6 to 8 °F: 0 days8 to 10 °F: 0 days10 to 12 °F: 0 days12 to 14 °F: 0 days14 to 16 °F: 0 days16 to 18 °F: 0 days18 to 20 °F: 0 daysdashed: P50 |e| 6.38 · P90 |e| 14.48 °F-200+20 °Fn = 23 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
-18.00-16.001
-16.00-14.002
-14.00-12.002
-12.00-10.001
-10.00-8.001
-8.00-6.006
-6.00-4.002
-4.00-2.001
-2.00+0.004
+0.00+2.003
+2.00+4.000
+4.00+6.000
+6.00+8.000
+8.00+10.000
+10.00+12.000
+12.00+14.000
+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
2026-08236.66 -6.37

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-08 → 2026-08-30 23
ECMWF AIFS Single2026-08-08 → 2026-08-30 23
ECMWF AIFS Single2026-08-08 → 2026-08-30 23
ECMWF AIFS Single2026-08-08 → 2026-08-30 23

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
NCEP GFS 23 +0.30 [-0.87, 1.56] no
GraphCast (IFS init) 23 -1.97 [-3.37, -0.24] yes
ECMWF IFS HRES 18 +1.88 [0.85, 4.75] yes
Persistence (baseline) 23 -1.61 [-3.56, 0.16] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KDEN (Denver Intl), model aifs_single, 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/KDEN/model/aifs_single/lead/7/

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

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