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

Denver Intl · ECMWF AIFS Single · lead day 5

KDEN · aifs_single · lead 5

Target day = initialization date + 5 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
tmax00Zbilinear30d25 1 QC4.62 [3.71, 5.40]2.44-4.52 [-5.26, -3.69]5.38 [4.41, 6.11]12% [4%, 20%]24%32%+0.33+0.652026-08-06 → 2026-08-30
tmax00Zbilinear90d25 1 QC4.62 [3.57, 5.42]2.44-4.52 [-5.28, -3.57]5.38 [4.19, 6.12]12% [3%, 21%]24%32%+0.33+0.652026-08-06 → 2026-08-30
tmax00Zbilinear365d25 1 QC4.62 [3.59, 5.50]2.44-4.52 [-5.37, -3.59]5.38 [4.21, 6.20]12% [0%, 20%]24%32%+0.33+0.652026-08-06 → 2026-08-30
tmax00Zbilinearall25 1 QC4.62 [3.60, 5.44]2.44-4.52 [-5.34, -3.58]5.38 [4.21, 6.21]12% [0%, 21%]24%32%+0.33+0.652026-08-06 → 2026-08-30
tmax00Znearest30d25 1 QC4.74 [3.87, 5.52]2.42-4.63 [-5.40, -3.83]5.47 [4.48, 6.24]8% [0%, 18%]20%36%+0.31+0.652026-08-06 → 2026-08-30
tmax00Znearest90d25 1 QC4.74 [3.75, 5.52]2.42-4.63 [-5.40, -3.75]5.47 [4.27, 6.27]8% [0%, 20%]20%36%+0.31+0.652026-08-06 → 2026-08-30
tmax00Znearest365d25 1 QC4.74 [3.77, 5.61]2.42-4.63 [-5.48, -3.77]5.47 [4.31, 6.34]8% [0%, 18%]20%36%+0.31+0.652026-08-06 → 2026-08-30
tmax00Znearestall25 1 QC4.74 [3.77, 5.58]2.42-4.63 [-5.46, -3.73]5.47 [4.28, 6.35]8% [0%, 19%]20%36%+0.31+0.652026-08-06 → 2026-08-30
tmax12Zbilinear30d24 1 QC4.45 [3.72, 5.19]2.28-4.35 [-5.13, -3.63]5.21 [4.39, 6.08]8% [0%, 26%]21%29%+0.34+0.672026-08-06 → 2026-08-30
tmax12Zbilinear90d24 1 QC4.45 [3.70, 5.23]2.28-4.35 [-5.20, -3.58]5.21 [4.34, 6.10]8% [0%, 33%]21%29%+0.34+0.672026-08-06 → 2026-08-30
tmax12Zbilinear365d24 1 QC4.45 [3.65, 5.40]2.28-4.35 [-5.36, -3.55]5.21 [4.36, 6.28]8% [0%, 31%]21%29%+0.34+0.672026-08-06 → 2026-08-30
tmax12Zbilinearall24 1 QC4.45 [3.61, 5.32]2.28-4.35 [-5.32, -3.55]5.21 [4.25, 6.20]8% [0%, 32%]21%29%+0.34+0.672026-08-06 → 2026-08-30
tmax12Znearest30d24 1 QC4.57 [3.86, 5.36]2.27-4.45 [-5.30, -3.71]5.30 [4.41, 6.24]4% [0%, 15%]21%33%+0.32+0.672026-08-06 → 2026-08-30
tmax12Znearest90d24 1 QC4.57 [3.83, 5.37]2.27-4.45 [-5.32, -3.68]5.30 [4.36, 6.29]4% [0%, 19%]21%33%+0.32+0.672026-08-06 → 2026-08-30
tmax12Znearest365d24 1 QC4.57 [3.79, 5.58]2.27-4.45 [-5.53, -3.69]5.30 [4.40, 6.43]4% [0%, 17%]21%33%+0.32+0.672026-08-06 → 2026-08-30
tmax12Znearestall24 1 QC4.57 [3.73, 5.49]2.27-4.45 [-5.48, -3.69]5.30 [4.31, 6.37]4% [0%, 18%]21%33%+0.32+0.672026-08-06 → 2026-08-30
tmin00Zbilinear30d25 1 QC2.64 [1.54, 3.64]2.19+1.70 [0.56, 2.96]3.18 [2.06, 3.91]24% [0%, 52%]40%56%+0.53+0.622026-08-06 → 2026-08-30
tmin00Zbilinear90d25 1 QC2.64 [1.35, 3.80]2.19+1.70 [0.22, 3.18]3.18 [1.89, 4.06]24% [0%, 57%]40%56%+0.53+0.622026-08-06 → 2026-08-30
tmin00Zbilinear365d25 1 QC2.64 [1.31, 3.84]2.19+1.70 [0.19, 3.50]3.18 [1.84, 4.08]24% [0%, 58%]40%56%+0.53+0.622026-08-06 → 2026-08-30
tmin00Zbilinearall25 1 QC2.64 [1.34, 3.82]2.19+1.70 [0.21, 3.24]3.18 [1.85, 4.06]24% [0%, 57%]40%56%+0.53+0.622026-08-06 → 2026-08-30
tmin00Znearest30d25 1 QC2.73 [1.64, 3.71]2.24+1.72 [0.49, 3.04]3.26 [2.13, 4.01]20% [0%, 45%]36%52%+0.52+0.612026-08-06 → 2026-08-30
tmin00Znearest90d25 1 QC2.73 [1.46, 3.87]2.24+1.72 [0.23, 3.28]3.26 [1.97, 4.15]20% [0%, 50%]36%52%+0.52+0.612026-08-06 → 2026-08-30
tmin00Znearest365d25 1 QC2.73 [1.42, 3.92]2.24+1.72 [0.24, 3.57]3.26 [1.93, 4.19]20% [0%, 50%]36%52%+0.52+0.612026-08-06 → 2026-08-30
tmin00Znearestall25 1 QC2.73 [1.44, 3.86]2.24+1.72 [0.22, 3.27]3.26 [1.92, 4.13]20% [0%, 50%]36%52%+0.52+0.612026-08-06 → 2026-08-30
tmin12Zbilinear30d24 1 QC2.48 [1.52, 3.36]2.08+1.65 [0.41, 2.95]3.08 [2.11, 3.80]29% [7%, 55%]46%58%+0.52+0.592026-08-06 → 2026-08-30
tmin12Zbilinear90d24 1 QC2.48 [1.36, 3.53]2.08+1.65 [0.08, 3.24]3.08 [1.94, 3.96]29% [0%, 60%]46%58%+0.52+0.592026-08-06 → 2026-08-30
tmin12Zbilinear365d24 1 QC2.48 [1.29, 3.69]2.08+1.65 [0.05, 3.49]3.08 [1.87, 4.02]29% [0%, 60%]46%58%+0.52+0.592026-08-06 → 2026-08-30
tmin12Zbilinearall24 1 QC2.48 [1.35, 3.51]2.08+1.65 [-0.07, 3.27]3.08 [1.91, 3.95]29% [0%, 60%]46%58%+0.52+0.592026-08-06 → 2026-08-30
tmin12Znearest30d24 1 QC2.57 [1.62, 3.41]2.15+1.68 [0.36, 3.00]3.15 [2.16, 3.86]29% [3%, 62%]46%62%+0.50+0.572026-08-06 → 2026-08-30
tmin12Znearest90d24 1 QC2.57 [1.49, 3.60]2.15+1.68 [0.10, 3.30]3.15 [2.03, 4.03]29% [0%, 67%]46%62%+0.50+0.572026-08-06 → 2026-08-30
tmin12Znearest365d24 1 QC2.57 [1.43, 3.73]2.15+1.68 [0.08, 3.55]3.15 [1.99, 4.08]29% [0%, 67%]46%62%+0.50+0.572026-08-06 → 2026-08-30
tmin12Znearestall24 1 QC2.57 [1.47, 3.56]2.15+1.68 [0.07, 3.27]3.15 [2.04, 3.98]29% [0%, 67%]46%62%+0.50+0.572026-08-06 → 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 5, 00Z bilinear tmax+10+50-5-102026-08-06: -6.99 °F2026-08-07: -0.25 °F2026-08-08: -2.06 °F2026-08-09: -1.35 °F2026-08-10: -1.98 °F2026-08-11: -8.76 °F2026-08-12: -8.42 °F2026-08-13: -7.76 °F2026-08-14: -7.76 °F2026-08-15: -2.51 °F2026-08-16: -0.81 °F2026-08-17: -6.58 °F2026-08-18: +1.29 °F2026-08-19: -9.14 °F2026-08-20: -5.22 °F2026-08-21: -8.68 °F2026-08-22: -3.33 °F2026-08-23: -5.15 °F2026-08-24: -3.74 °F2026-08-25: -0.92 °F2026-08-26: -4.37 °F2026-08-27: -3.73 °F2026-08-28: -4.5 °F2026-08-29: -5.62 °F2026-08-30: -4.54 °F2026-08-062026-08-30°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 (25 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-4.54
2026-08-29-5.62
2026-08-28-4.50
2026-08-27-3.73
2026-08-26-4.37
2026-08-25-0.92
2026-08-24-3.74
2026-08-23-5.15
2026-08-22-3.33
2026-08-21-8.68
2026-08-20-5.22
2026-08-19-9.14
2026-08-18+1.29
2026-08-17-6.58
2026-08-16-0.81
2026-08-15-2.51
2026-08-14-7.76
2026-08-13-7.76
2026-08-12-8.42
2026-08-11-8.76
2026-08-10-1.98
2026-08-09-1.35
2026-08-08-2.06
2026-08-07-0.25
2026-08-06-6.99

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KDEN, lead day 5-10 to -9 °F: 1 day-9 to -8 °F: 3 days-8 to -7 °F: 2 days-7 to -6 °F: 2 days-6 to -5 °F: 3 days-5 to -4 °F: 3 days-4 to -3 °F: 3 days-3 to -2 °F: 2 days-2 to -1 °F: 2 days-1 to 0 °F: 3 days0 to 1 °F: 0 days1 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| 4.5 · P90 |e| 8.58 °F-100+10 °Fn = 25 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
-10.00-9.001
-9.00-8.003
-8.00-7.002
-7.00-6.002
-6.00-5.003
-5.00-4.003
-4.00-3.003
-3.00-2.002
-2.00-1.002
-1.00+0.003
+0.00+1.000
+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
2026-08254.62 -4.52

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-06 → 2026-08-30 25
ECMWF AIFS Single2026-08-06 → 2026-08-30 25
ECMWF AIFS Single2026-08-06 → 2026-08-30 24
ECMWF AIFS Single2026-08-06 → 2026-08-30 24

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 25 -0.22 [-1.43, 1.38] no
GraphCast (IFS init) 25 -2.84 [-3.46, -2.23] yes
ECMWF IFS HRES 18 +1.77 [0.54, 4.56] yes
Persistence (baseline) 25 -2.30 [-4.45, 1.00] no

Cite this page

ShortCastCheck, KDEN aifs_single lead 5, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KDEN/model/aifs_single/lead/5/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KDEN (Denver Intl), model aifs_single, lead day 5. 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/5/

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