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

Oklahoma City · NCEP GFS · lead day 8

KOKC · gfs · lead 8

Target day = initialization date + 8 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, gfs-0p25, 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
tmax00Zbilinear30d22 2 QC4.09 [2.97, 5.01]4.09-0.03 [-2.61, 2.07]5.42 [4.02, 6.46]23% [8%, 38%]41%45%+0.22+0.202026-08-09 → 2026-08-30
tmax00Zbilinear90d22 2 QC4.09 [2.62, 4.97]4.09-0.03 [-3.03, 2.28]5.42 [3.55, 6.51]23% [8%, 41%]41%45%+0.22+0.202026-08-09 → 2026-08-30
tmax00Zbilinear365d22 2 QC4.09 [2.39, 5.06]4.09-0.03 [-3.18, 2.47]5.42 [3.11, 6.59]23% [5%, 39%]41%45%+0.22+0.202026-08-09 → 2026-08-30
tmax00Zbilinearall22 2 QC4.09 [2.39, 5.17]4.09-0.03 [-3.10, 2.26]5.42 [3.04, 6.65]23% [0%, 41%]41%45%+0.22+0.202026-08-09 → 2026-08-30
tmax00Znearest30d22 2 QC4.11 [2.95, 5.08]4.12+0.11 [-2.48, 2.29]5.55 [4.03, 6.73]18% [5%, 35%]32%45%+0.22+0.192026-08-09 → 2026-08-30
tmax00Znearest90d22 2 QC4.11 [2.60, 5.04]4.12+0.11 [-2.86, 2.42]5.55 [3.51, 6.76]18% [0%, 40%]32%45%+0.22+0.192026-08-09 → 2026-08-30
tmax00Znearest365d22 2 QC4.11 [2.50, 5.10]4.12+0.11 [-3.03, 2.68]5.55 [3.03, 6.92]18% [0%, 38%]32%45%+0.22+0.192026-08-09 → 2026-08-30
tmax00Znearestall22 2 QC4.11 [2.51, 5.20]4.12+0.11 [-2.92, 2.47]5.55 [3.02, 6.97]18% [0%, 39%]32%45%+0.22+0.192026-08-09 → 2026-08-30
tmax12Zbilinear30d22 2 QC3.09 [2.27, 4.01]2.38+2.19 [0.14, 3.76]3.80 [2.86, 4.59]23% [7%, 40%]36%64%+0.41+0.532026-08-09 → 2026-08-30
tmax12Zbilinear90d22 2 QC3.09 [2.12, 4.19]2.38+2.19 [-0.59, 3.93]3.80 [2.64, 4.67]23% [0%, 43%]36%64%+0.41+0.532026-08-09 → 2026-08-30
tmax12Zbilinear365d22 2 QC3.09 [2.11, 4.22]2.38+2.19 [-0.73, 3.99]3.80 [2.61, 4.70]23% [0%, 44%]36%64%+0.41+0.532026-08-09 → 2026-08-30
tmax12Zbilinearall22 2 QC3.09 [2.16, 4.16]2.38+2.19 [-0.62, 3.93]3.80 [2.62, 4.67]23% [0%, 43%]36%64%+0.41+0.532026-08-09 → 2026-08-30
tmax12Znearest30d22 2 QC3.39 [2.61, 4.41]2.51+2.30 [-0.05, 3.94]4.19 [3.37, 5.02]18% [0%, 38%]32%59%+0.36+0.512026-08-09 → 2026-08-30
tmax12Znearest90d22 2 QC3.39 [2.53, 4.46]2.51+2.30 [-0.90, 4.10]4.19 [3.27, 5.15]18% [0%, 43%]32%59%+0.36+0.512026-08-09 → 2026-08-30
tmax12Znearest365d22 2 QC3.39 [2.51, 4.61]2.51+2.30 [-1.07, 4.16]4.19 [3.25, 5.27]18% [0%, 44%]32%59%+0.36+0.512026-08-09 → 2026-08-30
tmax12Znearestall22 2 QC3.39 [2.56, 4.51]2.51+2.30 [-0.90, 4.10]4.19 [3.18, 5.16]18% [0%, 43%]32%59%+0.36+0.512026-08-09 → 2026-08-30
tmin00Zbilinear30d22 2 QC4.90 [3.79, 6.58]4.59+1.71 [-0.04, 4.71]6.10 [4.89, 7.72]14% [0%, 25%]27%36%+0.01+0.062026-08-09 → 2026-08-30
tmin00Zbilinear90d22 2 QC4.90 [3.69, 7.12]4.59+1.71 [-0.38, 5.45]6.10 [4.77, 8.21]14% [0%, 27%]27%36%+0.01+0.062026-08-09 → 2026-08-30
tmin00Zbilinear365d22 2 QC4.90 [3.63, 7.00]4.59+1.71 [-0.34, 5.23]6.10 [4.74, 8.15]14% [0%, 29%]27%36%+0.01+0.062026-08-09 → 2026-08-30
tmin00Zbilinearall22 2 QC4.90 [3.44, 7.18]4.59+1.71 [-0.49, 5.46]6.10 [4.51, 8.35]14% [0%, 29%]27%36%+0.01+0.062026-08-09 → 2026-08-30
tmin00Znearest30d22 2 QC5.14 [3.87, 6.97]4.84+1.92 [0.01, 4.83]6.49 [5.10, 8.12]14% [0%, 28%]27%41%-0.04+0.012026-08-09 → 2026-08-30
tmin00Znearest90d22 2 QC5.14 [3.68, 7.54]4.84+1.92 [-0.44, 5.68]6.49 [4.83, 8.65]14% [0%, 33%]27%41%-0.04+0.012026-08-09 → 2026-08-30
tmin00Znearest365d22 2 QC5.14 [3.61, 7.48]4.84+1.92 [-0.50, 5.47]6.49 [4.81, 8.56]14% [0%, 31%]27%41%-0.04+0.012026-08-09 → 2026-08-30
tmin00Znearestall22 2 QC5.14 [3.48, 7.54]4.84+1.92 [-0.60, 5.73]6.49 [4.70, 8.65]14% [0%, 32%]27%41%-0.04+0.012026-08-09 → 2026-08-30
tmin12Zbilinear30d22 2 QC5.09 [4.40, 6.05]2.99+4.19 [2.79, 5.64]5.98 [4.91, 7.40]5% [0%, 12%]9%18%-0.03+0.392026-08-09 → 2026-08-30
tmin12Zbilinear90d22 2 QC5.09 [4.33, 6.36]2.99+4.19 [2.71, 6.03]5.98 [4.84, 7.75]5% [0%, 12%]9%18%-0.03+0.392026-08-09 → 2026-08-30
tmin12Zbilinear365d22 2 QC5.09 [4.26, 6.25]2.99+4.19 [2.43, 5.95]5.98 [4.83, 7.76]5% [0%, 14%]9%18%-0.03+0.392026-08-09 → 2026-08-30
tmin12Zbilinearall22 2 QC5.09 [4.26, 6.35]2.99+4.19 [2.59, 5.92]5.98 [4.72, 7.93]5% [0%, 14%]9%18%-0.03+0.392026-08-09 → 2026-08-30
tmin12Znearest30d22 2 QC5.20 [4.40, 6.18]3.25+4.33 [2.93, 5.75]6.18 [5.03, 7.57]0% [0%, 0%]9%27%-0.05+0.332026-08-09 → 2026-08-30
tmin12Znearest90d22 2 QC5.20 [4.29, 6.34]3.25+4.33 [2.77, 6.06]6.18 [4.88, 8.00]0% [0%, 0%]9%27%-0.05+0.332026-08-09 → 2026-08-30
tmin12Znearest365d22 2 QC5.20 [4.27, 6.28]3.25+4.33 [2.63, 6.07]6.18 [4.91, 7.85]0% [0%, 0%]9%27%-0.05+0.332026-08-09 → 2026-08-30
tmin12Znearestall22 2 QC5.20 [4.24, 6.37]3.25+4.33 [2.72, 5.95]6.18 [4.72, 8.03]0% [0%, 0%]9%27%-0.05+0.332026-08-09 → 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 NCEP GFS at KOKC, lead day 8, 00Z bilinear tmax+20+100-10-202026-08-09: -0.22 °F2026-08-10: -4.39 °F2026-08-11: -0.62 °F2026-08-12: -6.59 °F2026-08-13: -12.72 °F2026-08-14: +1.85 °F2026-08-15: -4.11 °F2026-08-16: -0.64 °F2026-08-17: +11.05 °F2026-08-18: -2.36 °F2026-08-19: +4.93 °F2026-08-20: +3.29 °F2026-08-21: -1.59 °F2026-08-22: +0.02 °F2026-08-23: +3.74 °F2026-08-24: +0.8 °F2026-08-25: -9.07 °F2026-08-26: +6.58 °F2026-08-27: -1.8 °F2026-08-28: +8.86 °F2026-08-29: +3.56 °F2026-08-30: -1.22 °F2026-08-092026-08-30°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 (22 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-1.22
2026-08-29+3.56
2026-08-28+8.86
2026-08-27-1.80
2026-08-26+6.58
2026-08-25-9.07
2026-08-24+0.80
2026-08-23+3.74
2026-08-22+0.02
2026-08-21-1.59
2026-08-20+3.29
2026-08-19+4.93
2026-08-18-2.36
2026-08-17+11.05
2026-08-16-0.64
2026-08-15-4.11
2026-08-14+1.85
2026-08-13-12.72
2026-08-12-6.59
2026-08-11-0.62
2026-08-10-4.39
2026-08-09-0.22

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KOKC, lead day 8-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 1 day-12 to -10 °F: 0 days-10 to -8 °F: 1 day-8 to -6 °F: 1 day-6 to -4 °F: 2 days-4 to -2 °F: 1 day-2 to 0 °F: 6 days0 to 2 °F: 3 days2 to 4 °F: 3 days4 to 6 °F: 1 day6 to 8 °F: 1 day8 to 10 °F: 1 day10 to 12 °F: 1 day12 to 14 °F: 0 days14 to 16 °F: 0 days16 to 18 °F: 0 days18 to 20 °F: 0 daysdashed: P50 |e| 3.42 · P90 |e| 9.05 °F-200+20 °Fn = 22 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
-14.00-12.001
-12.00-10.000
-10.00-8.001
-8.00-6.001
-6.00-4.002
-4.00-2.001
-2.00+0.006
+0.00+2.003
+2.00+4.003
+4.00+6.001
+6.00+8.001
+8.00+10.001
+10.00+12.001
+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
2026-08224.09 -0.03

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-09 → 2026-08-30 22
NCEP GFS2026-08-09 → 2026-08-30 22
NCEP GFS2026-08-09 → 2026-08-30 22
NCEP GFS2026-08-09 → 2026-08-30 22

Compared with other models

Paired bootstrap on the days both models cover (90d, 00Z, bilinear, daily maximum). Negative means NCEP GFS has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 22 -2.77 [-5.42, -1.10] yes
GraphCast (IFS init) 22 -6.63 [-8.60, -5.21] yes
ECMWF IFS HRES 17 +0.91 [-0.43, 2.31] no
Persistence (baseline) 22 -1.18 [-3.76, 0.64] no

Cite this page

ShortCastCheck, KOKC gfs lead 8, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KOKC/model/gfs/lead/8/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KOKC (Oklahoma City), model gfs, lead day 8. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KOKC/model/gfs/lead/8/

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