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

Oklahoma City · ECMWF AIFS Single · lead day 4

KOKC · aifs_single · lead 4

Target day = initialization date + 4 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
tmax00Zbilinear30d26 2 QC3.92 [3.10, 5.38]2.57-3.25 [-5.24, -1.77]4.74 [3.60, 6.39]12% [3%, 22%]27%38%+0.01+0.342026-08-05 → 2026-08-30
tmax00Zbilinear90d26 2 QC3.92 [3.08, 5.66]2.57-3.25 [-5.66, -1.78]4.74 [3.54, 6.59]12% [0%, 23%]27%38%+0.01+0.342026-08-05 → 2026-08-30
tmax00Zbilinear365d26 2 QC3.92 [3.02, 5.62]2.57-3.25 [-5.53, -1.55]4.74 [3.51, 6.56]12% [0%, 22%]27%38%+0.01+0.342026-08-05 → 2026-08-30
tmax00Zbilinearall26 2 QC3.92 [3.08, 5.92]2.57-3.25 [-5.92, -1.45]4.74 [3.58, 6.73]12% [0%, 21%]27%38%+0.01+0.342026-08-05 → 2026-08-30
tmax00Znearest30d26 2 QC3.95 [3.08, 5.39]2.62-3.26 [-5.29, -1.83]4.79 [3.60, 6.43]12% [3%, 22%]31%38%+0.00+0.332026-08-05 → 2026-08-30
tmax00Znearest90d26 2 QC3.95 [3.08, 5.63]2.62-3.26 [-5.63, -1.83]4.79 [3.53, 6.64]12% [0%, 23%]31%38%+0.00+0.332026-08-05 → 2026-08-30
tmax00Znearest365d26 2 QC3.95 [3.03, 5.61]2.62-3.26 [-5.56, -1.62]4.79 [3.51, 6.63]12% [0%, 22%]31%38%+0.00+0.332026-08-05 → 2026-08-30
tmax00Znearestall26 2 QC3.95 [3.07, 5.91]2.62-3.26 [-5.91, -1.53]4.79 [3.61, 6.77]12% [0%, 21%]31%38%+0.00+0.332026-08-05 → 2026-08-30
tmax12Zbilinear30d26 2 QC3.63 [3.06, 4.48]1.78-3.27 [-4.41, -2.30]4.05 [3.41, 4.92]4% [0%, 11%]23%35%+0.08+0.552026-08-05 → 2026-08-30
tmax12Zbilinear90d26 2 QC3.63 [3.05, 4.69]1.78-3.27 [-4.69, -2.25]4.05 [3.39, 5.08]4% [0%, 11%]23%35%+0.08+0.552026-08-05 → 2026-08-30
tmax12Zbilinear365d26 2 QC3.63 [3.05, 4.65]1.78-3.27 [-4.58, -2.16]4.05 [3.39, 5.07]4% [0%, 11%]23%35%+0.08+0.552026-08-05 → 2026-08-30
tmax12Zbilinearall26 2 QC3.63 [3.07, 4.77]1.78-3.27 [-4.77, -2.17]4.05 [3.39, 5.08]4% [0%, 12%]23%35%+0.08+0.552026-08-05 → 2026-08-30
tmax12Znearest30d26 2 QC3.63 [3.01, 4.52]1.80-3.31 [-4.45, -2.39]4.10 [3.38, 4.98]8% [0%, 18%]27%35%+0.08+0.542026-08-05 → 2026-08-30
tmax12Znearest90d26 2 QC3.63 [3.01, 4.71]1.80-3.31 [-4.71, -2.34]4.10 [3.36, 5.13]8% [0%, 19%]27%35%+0.08+0.542026-08-05 → 2026-08-30
tmax12Znearest365d26 2 QC3.63 [3.01, 4.67]1.80-3.31 [-4.67, -2.28]4.10 [3.35, 5.13]8% [0%, 20%]27%35%+0.08+0.542026-08-05 → 2026-08-30
tmax12Znearestall26 2 QC3.63 [3.02, 4.75]1.80-3.31 [-4.74, -2.30]4.10 [3.36, 5.18]8% [0%, 20%]27%35%+0.08+0.542026-08-05 → 2026-08-30
tmin00Zbilinear30d26 2 QC3.25 [2.47, 4.30]2.09+2.82 [1.44, 4.16]3.84 [2.91, 4.75]15% [4%, 25%]31%54%+0.25+0.512026-08-05 → 2026-08-30
tmin00Zbilinear90d26 2 QC3.25 [2.34, 4.53]2.09+2.82 [1.22, 4.48]3.84 [2.71, 4.92]15% [0%, 27%]31%54%+0.25+0.512026-08-05 → 2026-08-30
tmin00Zbilinear365d26 2 QC3.25 [2.32, 4.43]2.09+2.82 [1.02, 4.43]3.84 [2.75, 4.91]15% [0%, 27%]31%54%+0.25+0.512026-08-05 → 2026-08-30
tmin00Zbilinearall26 2 QC3.25 [2.33, 4.48]2.09+2.82 [1.27, 4.46]3.84 [2.72, 4.96]15% [0%, 27%]31%54%+0.25+0.512026-08-05 → 2026-08-30
tmin00Znearest30d26 2 QC3.36 [2.59, 4.38]2.11+2.86 [1.35, 4.22]3.89 [2.98, 4.81]8% [0%, 17%]27%46%+0.22+0.502026-08-05 → 2026-08-30
tmin00Znearest90d26 2 QC3.36 [2.45, 4.64]2.11+2.86 [1.14, 4.54]3.89 [2.80, 4.99]8% [0%, 18%]27%46%+0.22+0.502026-08-05 → 2026-08-30
tmin00Znearest365d26 2 QC3.36 [2.43, 4.56]2.11+2.86 [0.86, 4.56]3.89 [2.84, 4.98]8% [0%, 18%]27%46%+0.22+0.502026-08-05 → 2026-08-30
tmin00Znearestall26 2 QC3.36 [2.48, 4.57]2.11+2.86 [1.21, 4.56]3.89 [2.82, 4.99]8% [0%, 19%]27%46%+0.22+0.502026-08-05 → 2026-08-30
tmin12Zbilinear30d26 2 QC3.27 [2.40, 4.52]1.92+2.94 [1.78, 4.32]3.82 [2.78, 4.98]12% [0%, 23%]31%46%+0.24+0.552026-08-05 → 2026-08-30
tmin12Zbilinear90d26 2 QC3.27 [2.33, 4.86]1.92+2.94 [1.60, 4.81]3.82 [2.71, 5.28]12% [0%, 24%]31%46%+0.24+0.552026-08-05 → 2026-08-30
tmin12Zbilinear365d26 2 QC3.27 [2.31, 4.79]1.92+2.94 [1.60, 4.79]3.82 [2.71, 5.19]12% [0%, 24%]31%46%+0.24+0.552026-08-05 → 2026-08-30
tmin12Zbilinearall26 2 QC3.27 [2.25, 4.91]1.92+2.94 [1.64, 4.83]3.82 [2.62, 5.25]12% [0%, 24%]31%46%+0.24+0.552026-08-05 → 2026-08-30
tmin12Znearest30d26 2 QC3.32 [2.42, 4.54]1.91+2.99 [1.76, 4.43]3.84 [2.82, 4.98]8% [0%, 17%]31%46%+0.23+0.552026-08-05 → 2026-08-30
tmin12Znearest90d26 2 QC3.32 [2.38, 4.90]1.91+2.99 [1.55, 4.89]3.84 [2.76, 5.31]8% [0%, 18%]31%46%+0.23+0.552026-08-05 → 2026-08-30
tmin12Znearest365d26 2 QC3.32 [2.37, 4.87]1.91+2.99 [1.49, 4.87]3.84 [2.75, 5.24]8% [0%, 18%]31%46%+0.23+0.552026-08-05 → 2026-08-30
tmin12Znearestall26 2 QC3.32 [2.31, 4.93]1.91+2.99 [1.56, 4.92]3.84 [2.69, 5.31]8% [0%, 18%]31%46%+0.23+0.552026-08-05 → 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 4, 00Z bilinear tmax+20+100-10-202026-08-05: -3.78 °F2026-08-06: -11.79 °F2026-08-07: -9.13 °F2026-08-08: -3.17 °F2026-08-09: -2.07 °F2026-08-10: -2.88 °F2026-08-11: -1.67 °F2026-08-12: -1.87 °F2026-08-13: -4.41 °F2026-08-14: -5.62 °F2026-08-15: -2.18 °F2026-08-16: -0.73 °F2026-08-17: -3.46 °F2026-08-18: -5.54 °F2026-08-19: -0.59 °F2026-08-20: -4.13 °F2026-08-21: +3.42 °F2026-08-22: -1 °F2026-08-23: +5.32 °F2026-08-24: -4.01 °F2026-08-25: -6.53 °F2026-08-26: -0.05 °F2026-08-27: -1.32 °F2026-08-28: -6.21 °F2026-08-29: -6.27 °F2026-08-30: -4.78 °F2026-08-052026-08-30°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 (26 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-4.78
2026-08-29-6.27
2026-08-28-6.21
2026-08-27-1.32
2026-08-26-0.05
2026-08-25-6.53
2026-08-24-4.01
2026-08-23+5.32
2026-08-22-1.00
2026-08-21+3.42
2026-08-20-4.13
2026-08-19-0.59
2026-08-18-5.54
2026-08-17-3.46
2026-08-16-0.73
2026-08-15-2.18
2026-08-14-5.62
2026-08-13-4.41
2026-08-12-1.87
2026-08-11-1.67
2026-08-10-2.88
2026-08-09-2.07
2026-08-08-3.17
2026-08-07-9.13
2026-08-06-11.79
2026-08-05-3.78

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KOKC, lead day 4-20 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: 1 day-10 to -8 °F: 1 day-8 to -6 °F: 3 days-6 to -4 °F: 6 days-4 to -2 °F: 6 days-2 to 0 °F: 7 days0 to 2 °F: 0 days2 to 4 °F: 1 day4 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| 3.62 · P90 |e| 6.4 °F-200+20 °Fn = 26 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
-12.00-10.001
-10.00-8.001
-8.00-6.003
-6.00-4.006
-4.00-2.006
-2.00+0.007
+0.00+2.000
+2.00+4.001
+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
2026-08263.92 -3.25

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-05 → 2026-08-30 26
ECMWF AIFS Single2026-08-05 → 2026-08-30 26
ECMWF AIFS Single2026-08-05 → 2026-08-30 26
ECMWF AIFS Single2026-08-05 → 2026-08-30 26

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 26 +0.93 [-0.81, 3.24] no
GraphCast (IFS init) 25 -4.56 [-6.17, -1.90] yes
ECMWF IFS HRES 20 -0.11 [-0.50, 0.86] no
Persistence (baseline) 26 -0.04 [-1.35, 1.23] no

Cite this page

ShortCastCheck, KOKC aifs_single lead 4, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KOKC/model/aifs_single/lead/4/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KOKC (Oklahoma City), model aifs_single, lead day 4. 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/4/

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