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

Oklahoma City · ECMWF AIFS Single · lead day 6

KOKC · aifs_single · lead 6

Target day = initialization date + 6 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, 2 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
tmax00Zbilinear30d24 2 QC4.53 [3.67, 5.56]3.11-3.83 [-5.25, -2.79]5.49 [4.57, 6.42]17% [6%, 25%]29%33%-0.28+0.132026-08-07 → 2026-08-30
tmax00Zbilinear90d24 2 QC4.53 [3.66, 5.79]3.11-3.83 [-5.50, -2.85]5.49 [4.51, 6.62]17% [4%, 26%]29%33%-0.28+0.132026-08-07 → 2026-08-30
tmax00Zbilinear365d24 2 QC4.53 [3.66, 5.82]3.11-3.83 [-5.54, -2.66]5.49 [4.53, 6.70]17% [0%, 29%]29%33%-0.28+0.132026-08-07 → 2026-08-30
tmax00Zbilinearall24 2 QC4.53 [3.57, 5.79]3.11-3.83 [-5.68, -2.73]5.49 [4.46, 6.59]17% [0%, 29%]29%33%-0.28+0.132026-08-07 → 2026-08-30
tmax00Znearest30d24 2 QC4.59 [3.80, 5.55]3.09-3.92 [-5.20, -2.97]5.55 [4.67, 6.43]17% [6%, 25%]29%33%-0.30+0.142026-08-07 → 2026-08-30
tmax00Znearest90d24 2 QC4.59 [3.76, 5.76]3.09-3.92 [-5.54, -2.99]5.55 [4.59, 6.60]17% [4%, 26%]29%33%-0.30+0.142026-08-07 → 2026-08-30
tmax00Znearest365d24 2 QC4.59 [3.71, 5.87]3.09-3.92 [-5.54, -2.82]5.55 [4.54, 6.71]17% [0%, 29%]29%33%-0.30+0.142026-08-07 → 2026-08-30
tmax00Znearestall24 2 QC4.59 [3.69, 5.80]3.09-3.92 [-5.61, -2.87]5.55 [4.54, 6.57]17% [0%, 29%]29%33%-0.30+0.142026-08-07 → 2026-08-30
tmax12Zbilinear30d24 2 QC4.68 [3.58, 6.61]3.35-3.69 [-6.33, -2.03]5.98 [4.14, 8.52]12% [4%, 21%]17%33%-0.32+0.072026-08-07 → 2026-08-30
tmax12Zbilinear90d24 2 QC4.68 [3.49, 7.32]3.35-3.69 [-7.16, -2.02]5.98 [4.00, 9.23]12% [0%, 22%]17%33%-0.32+0.072026-08-07 → 2026-08-30
tmax12Zbilinear365d24 2 QC4.68 [3.52, 7.11]3.35-3.69 [-6.96, -1.81]5.98 [4.04, 9.08]12% [0%, 24%]17%33%-0.32+0.072026-08-07 → 2026-08-30
tmax12Zbilinearall24 2 QC4.68 [3.44, 7.13]3.35-3.69 [-7.09, -1.88]5.98 [3.89, 9.08]12% [0%, 23%]17%33%-0.32+0.072026-08-07 → 2026-08-30
tmax12Znearest30d24 2 QC4.72 [3.58, 6.62]3.42-3.74 [-6.29, -2.15]6.02 [4.20, 8.46]12% [4%, 21%]17%38%-0.33+0.052026-08-07 → 2026-08-30
tmax12Znearest90d24 2 QC4.72 [3.52, 7.26]3.42-3.74 [-7.03, -2.12]6.02 [4.10, 9.10]12% [0%, 22%]17%38%-0.33+0.052026-08-07 → 2026-08-30
tmax12Znearest365d24 2 QC4.72 [3.55, 7.08]3.42-3.74 [-6.97, -1.99]6.02 [4.05, 9.00]12% [0%, 24%]17%38%-0.33+0.052026-08-07 → 2026-08-30
tmax12Znearestall24 2 QC4.72 [3.47, 7.02]3.42-3.74 [-7.01, -2.00]6.02 [3.91, 8.96]12% [0%, 23%]17%38%-0.33+0.052026-08-07 → 2026-08-30
tmin00Zbilinear30d24 2 QC3.82 [3.28, 4.31]2.59+2.91 [1.76, 3.85]4.40 [3.69, 4.97]12% [0%, 27%]29%33%+0.02+0.352026-08-07 → 2026-08-30
tmin00Zbilinear90d24 2 QC3.82 [3.30, 4.29]2.59+2.91 [1.42, 3.91]4.40 [3.70, 4.96]12% [0%, 27%]29%33%+0.02+0.352026-08-07 → 2026-08-30
tmin00Zbilinear365d24 2 QC3.82 [3.26, 4.40]2.59+2.91 [1.56, 4.05]4.40 [3.67, 5.09]12% [0%, 29%]29%33%+0.02+0.352026-08-07 → 2026-08-30
tmin00Zbilinearall24 2 QC3.82 [3.27, 4.35]2.59+2.91 [1.49, 4.02]4.40 [3.68, 5.02]12% [0%, 29%]29%33%+0.02+0.352026-08-07 → 2026-08-30
tmin00Znearest30d24 2 QC3.97 [3.36, 4.53]2.66+3.00 [1.76, 4.04]4.52 [3.76, 5.14]8% [0%, 16%]25%29%-0.01+0.332026-08-07 → 2026-08-30
tmin00Znearest90d24 2 QC3.97 [3.37, 4.50]2.66+3.00 [1.39, 4.12]4.52 [3.78, 5.12]8% [0%, 16%]25%29%-0.01+0.332026-08-07 → 2026-08-30
tmin00Znearest365d24 2 QC3.97 [3.33, 4.62]2.66+3.00 [1.53, 4.24]4.52 [3.77, 5.26]8% [0%, 16%]25%29%-0.01+0.332026-08-07 → 2026-08-30
tmin00Znearestall24 2 QC3.97 [3.30, 4.58]2.66+3.00 [1.49, 4.21]4.52 [3.77, 5.17]8% [0%, 16%]25%29%-0.01+0.332026-08-07 → 2026-08-30
tmin12Zbilinear30d24 2 QC3.41 [2.70, 3.91]2.33+2.88 [1.91, 3.69]4.00 [3.34, 4.44]17% [0%, 38%]29%42%+0.13+0.422026-08-07 → 2026-08-30
tmin12Zbilinear90d24 2 QC3.41 [2.61, 3.90]2.33+2.88 [1.75, 3.72]4.00 [3.27, 4.44]17% [0%, 45%]29%42%+0.13+0.422026-08-07 → 2026-08-30
tmin12Zbilinear365d24 2 QC3.41 [2.63, 3.95]2.33+2.88 [1.74, 3.86]4.00 [3.28, 4.53]17% [0%, 45%]29%42%+0.13+0.422026-08-07 → 2026-08-30
tmin12Zbilinearall24 2 QC3.41 [2.52, 3.98]2.33+2.88 [1.65, 3.82]4.00 [3.13, 4.54]17% [0%, 50%]29%42%+0.13+0.422026-08-07 → 2026-08-30
tmin12Znearest30d24 2 QC3.53 [2.75, 4.03]2.37+2.94 [1.90, 3.80]4.08 [3.42, 4.49]17% [0%, 38%]25%42%+0.10+0.412026-08-07 → 2026-08-30
tmin12Znearest90d24 2 QC3.53 [2.63, 4.02]2.37+2.94 [1.68, 3.89]4.08 [3.38, 4.50]17% [0%, 45%]25%42%+0.10+0.412026-08-07 → 2026-08-30
tmin12Znearest365d24 2 QC3.53 [2.68, 4.11]2.37+2.94 [1.75, 4.03]4.08 [3.37, 4.55]17% [0%, 45%]25%42%+0.10+0.412026-08-07 → 2026-08-30
tmin12Znearestall24 2 QC3.53 [2.52, 4.10]2.37+2.94 [1.63, 3.97]4.08 [3.20, 4.57]17% [0%, 50%]25%42%+0.10+0.412026-08-07 → 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 KOKC, lead day 6, 00Z bilinear tmax+20+100-10-202026-08-07: -4.53 °F2026-08-08: -11.64 °F2026-08-09: -6.37 °F2026-08-10: -3.2 °F2026-08-11: -0.75 °F2026-08-12: -2.12 °F2026-08-13: -3.83 °F2026-08-14: -8.35 °F2026-08-15: -1.87 °F2026-08-16: -6.89 °F2026-08-17: +5.56 °F2026-08-18: -5.67 °F2026-08-19: +0.67 °F2026-08-20: -10.98 °F2026-08-21: -4.73 °F2026-08-22: +1.69 °F2026-08-23: +0.44 °F2026-08-24: -3.49 °F2026-08-25: -7.74 °F2026-08-26: -0.15 °F2026-08-27: -1.63 °F2026-08-28: -5.23 °F2026-08-29: -4.81 °F2026-08-30: -6.35 °F2026-08-072026-08-30°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 (24 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-6.35
2026-08-29-4.81
2026-08-28-5.23
2026-08-27-1.63
2026-08-26-0.15
2026-08-25-7.74
2026-08-24-3.49
2026-08-23+0.44
2026-08-22+1.69
2026-08-21-4.73
2026-08-20-10.98
2026-08-19+0.67
2026-08-18-5.67
2026-08-17+5.56
2026-08-16-6.89
2026-08-15-1.87
2026-08-14-8.35
2026-08-13-3.83
2026-08-12-2.12
2026-08-11-0.75
2026-08-10-3.20
2026-08-09-6.37
2026-08-08-11.64
2026-08-07-4.53

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KOKC, lead day 6-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 0 days-12 to -10 °F: 2 days-10 to -8 °F: 1 day-8 to -6 °F: 4 days-6 to -4 °F: 5 days-4 to -2 °F: 4 days-2 to 0 °F: 4 days0 to 2 °F: 3 days2 to 4 °F: 0 days4 to 6 °F: 1 day6 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| 4.63 · P90 |e| 8.16 °F-200+20 °Fn = 24 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
-18.00-16.000
-16.00-14.000
-14.00-12.000
-12.00-10.002
-10.00-8.001
-8.00-6.004
-6.00-4.005
-4.00-2.004
-2.00+0.004
+0.00+2.003
+2.00+4.000
+4.00+6.001
+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
2026-08244.53 -3.83

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-07 → 2026-08-30 24
ECMWF AIFS Single2026-08-07 → 2026-08-30 24
ECMWF AIFS Single2026-08-07 → 2026-08-30 24
ECMWF AIFS Single2026-08-07 → 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 24 +0.30 [-1.04, 2.34] no
GraphCast (IFS init) 24 -4.91 [-6.42, -2.99] yes
ECMWF IFS HRES 19 +1.61 [-0.38, 2.92] no
Persistence (baseline) 24 +0.99 [-0.53, 2.35] no

Cite this page

ShortCastCheck, KOKC aifs_single lead 6, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KOKC/model/aifs_single/lead/6/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KOKC (Oklahoma City), model aifs_single, lead day 6. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KOKC/model/aifs_single/lead/6/

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