Raw model output on the native 0.25° grid — no MOS, no bias correction, no post-processing. Scores understate operational forecast quality. Read the fairness statement →

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

Oklahoma City · NCEP GFS · lead day 1

KOKC · gfs · lead 1

Target day = initialization date + 1 day. 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
tmax00Zbilinear30d29 2 QC2.67 [1.75, 3.60]2.22+1.96 [1.07, 2.86]3.35 [2.25, 4.18]31% [13%, 50%]41%59%+0.23+0.362026-08-02 → 2026-08-30
tmax00Zbilinear90d29 2 QC2.67 [1.56, 3.74]2.22+1.96 [0.95, 3.06]3.35 [1.98, 4.27]31% [7%, 54%]41%59%+0.23+0.362026-08-02 → 2026-08-30
tmax00Zbilinear365d29 2 QC2.67 [1.38, 3.78]2.22+1.96 [0.85, 3.06]3.35 [1.76, 4.36]31% [9%, 59%]41%59%+0.23+0.362026-08-02 → 2026-08-30
tmax00Zbilinearall29 2 QC2.67 [1.47, 3.80]2.22+1.96 [0.89, 3.18]3.35 [1.89, 4.37]31% [10%, 57%]41%59%+0.23+0.362026-08-02 → 2026-08-30
tmax00Znearest30d29 2 QC2.95 [1.97, 3.98]2.25+2.23 [1.45, 3.09]3.61 [2.52, 4.49]28% [10%, 46%]34%52%+0.14+0.352026-08-02 → 2026-08-30
tmax00Znearest90d29 2 QC2.95 [1.72, 4.10]2.25+2.23 [1.27, 3.26]3.61 [2.18, 4.53]28% [5%, 52%]34%52%+0.14+0.352026-08-02 → 2026-08-30
tmax00Znearest365d29 2 QC2.95 [1.54, 4.17]2.25+2.23 [1.19, 3.32]3.61 [1.95, 4.60]28% [6%, 59%]34%52%+0.14+0.352026-08-02 → 2026-08-30
tmax00Znearestall29 2 QC2.95 [1.60, 4.10]2.25+2.23 [1.23, 3.37]3.61 [2.01, 4.58]28% [5%, 54%]34%52%+0.14+0.352026-08-02 → 2026-08-30
tmax12Zbilinear30d29 2 QC2.61 [1.54, 3.75]2.34+1.78 [0.61, 3.06]3.40 [2.09, 4.38]24% [8%, 39%]55%62%+0.24+0.322026-08-02 → 2026-08-30
tmax12Zbilinear90d29 2 QC2.61 [1.30, 3.93]2.34+1.78 [0.62, 3.33]3.40 [1.63, 4.49]24% [7%, 38%]55%62%+0.24+0.322026-08-02 → 2026-08-30
tmax12Zbilinear365d29 2 QC2.61 [1.22, 4.08]2.34+1.78 [0.51, 3.25]3.40 [1.38, 4.62]24% [6%, 40%]55%62%+0.24+0.322026-08-02 → 2026-08-30
tmax12Zbilinearall29 2 QC2.61 [1.23, 4.09]2.34+1.78 [0.51, 3.53]3.40 [1.43, 4.62]24% [5%, 40%]55%62%+0.24+0.322026-08-02 → 2026-08-30
tmax12Znearest30d29 2 QC2.67 [1.55, 3.86]2.34+1.90 [0.85, 3.20]3.51 [2.16, 4.57]28% [11%, 45%]55%66%+0.23+0.322026-08-02 → 2026-08-30
tmax12Znearest90d29 2 QC2.67 [1.29, 4.08]2.34+1.90 [0.84, 3.43]3.51 [1.61, 4.68]28% [8%, 45%]55%66%+0.23+0.322026-08-02 → 2026-08-30
tmax12Znearest365d29 2 QC2.67 [1.23, 4.26]2.34+1.90 [0.72, 3.36]3.51 [1.37, 4.82]28% [8%, 45%]55%66%+0.23+0.322026-08-02 → 2026-08-30
tmax12Znearestall29 2 QC2.67 [1.17, 4.28]2.34+1.90 [0.72, 3.59]3.51 [1.33, 4.78]28% [6%, 45%]55%66%+0.23+0.322026-08-02 → 2026-08-30
tmin00Zbilinear30d29 2 QC3.01 [2.32, 3.71]2.30+2.08 [0.21, 3.65]3.47 [2.66, 4.18]14% [3%, 25%]38%52%+0.07+0.292026-08-02 → 2026-08-30
tmin00Zbilinear90d29 2 QC3.01 [2.14, 3.97]2.30+2.08 [0.15, 3.97]3.47 [2.46, 4.42]14% [4%, 28%]38%52%+0.07+0.292026-08-02 → 2026-08-30
tmin00Zbilinear365d29 2 QC3.01 [2.08, 3.93]2.30+2.08 [-0.03, 3.92]3.47 [2.37, 4.34]14% [5%, 30%]38%52%+0.07+0.292026-08-02 → 2026-08-30
tmin00Zbilinearall29 2 QC3.01 [2.14, 3.96]2.30+2.08 [-0.15, 3.96]3.47 [2.38, 4.41]14% [0%, 30%]38%52%+0.07+0.292026-08-02 → 2026-08-30
tmin00Znearest30d29 2 QC3.30 [2.61, 3.99]2.55+2.12 [-0.08, 3.97]3.71 [2.94, 4.37]10% [0%, 21%]24%48%-0.02+0.222026-08-02 → 2026-08-30
tmin00Znearest90d29 2 QC3.30 [2.42, 4.23]2.55+2.12 [-0.16, 4.23]3.71 [2.71, 4.58]10% [0%, 26%]24%48%-0.02+0.222026-08-02 → 2026-08-30
tmin00Znearest365d29 2 QC3.30 [2.33, 4.20]2.55+2.12 [-0.32, 4.20]3.71 [2.64, 4.55]10% [0%, 29%]24%48%-0.02+0.222026-08-02 → 2026-08-30
tmin00Znearestall29 2 QC3.30 [2.42, 4.20]2.55+2.12 [-0.52, 4.20]3.71 [2.68, 4.59]10% [0%, 29%]24%48%-0.02+0.222026-08-02 → 2026-08-30
tmin12Zbilinear30d29 2 QC3.10 [2.34, 3.83]2.15+2.37 [0.78, 3.74]3.60 [2.75, 4.29]10% [3%, 20%]31%55%+0.04+0.342026-08-02 → 2026-08-30
tmin12Zbilinear90d29 2 QC3.10 [2.12, 3.93]2.15+2.37 [0.63, 3.92]3.60 [2.49, 4.34]10% [0%, 21%]31%55%+0.04+0.342026-08-02 → 2026-08-30
tmin12Zbilinear365d29 2 QC3.10 [2.07, 3.96]2.15+2.37 [0.49, 3.93]3.60 [2.44, 4.37]10% [0%, 23%]31%55%+0.04+0.342026-08-02 → 2026-08-30
tmin12Zbilinearall29 2 QC3.10 [2.15, 3.98]2.15+2.37 [0.44, 3.95]3.60 [2.47, 4.40]10% [0%, 22%]31%55%+0.04+0.342026-08-02 → 2026-08-30
tmin12Znearest30d29 2 QC3.44 [2.53, 4.32]2.40+2.60 [0.70, 4.25]3.98 [3.05, 4.76]14% [3%, 24%]21%52%-0.06+0.262026-08-02 → 2026-08-30
tmin12Znearest90d29 2 QC3.44 [2.31, 4.39]2.40+2.60 [0.51, 4.37]3.98 [2.79, 4.77]14% [0%, 27%]21%52%-0.06+0.262026-08-02 → 2026-08-30
tmin12Znearest365d29 2 QC3.44 [2.17, 4.43]2.40+2.60 [0.43, 4.39]3.98 [2.68, 4.84]14% [0%, 29%]21%52%-0.06+0.262026-08-02 → 2026-08-30
tmin12Znearestall29 2 QC3.44 [2.30, 4.46]2.40+2.60 [0.28, 4.40]3.98 [2.71, 4.86]14% [0%, 29%]21%52%-0.06+0.262026-08-02 → 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 1, 00Z bilinear tmax+10+50-5-102026-08-02: +2.73 °F2026-08-03: +5.59 °F2026-08-04: +2.73 °F2026-08-05: +3.14 °F2026-08-06: +5.06 °F2026-08-07: +5.62 °F2026-08-08: -3.06 °F2026-08-09: +2.68 °F2026-08-10: +1.74 °F2026-08-11: +1.4 °F2026-08-12: +0.95 °F2026-08-13: -0.36 °F2026-08-14: -1.14 °F2026-08-15: +2.76 °F2026-08-16: +2.57 °F2026-08-17: -0.17 °F2026-08-18: -0.77 °F2026-08-19: +4.45 °F2026-08-20: -4.28 °F2026-08-21: +5.71 °F2026-08-22: +8.07 °F2026-08-23: +3.59 °F2026-08-24: -0.51 °F2026-08-25: +0.25 °F2026-08-26: +3.42 °F2026-08-27: +3.39 °F2026-08-28: +0.6 °F2026-08-29: +0.65 °F2026-08-30: -0.1 °F2026-08-022026-08-30°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 (29 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-0.10
2026-08-29+0.65
2026-08-28+0.60
2026-08-27+3.39
2026-08-26+3.42
2026-08-25+0.25
2026-08-24-0.51
2026-08-23+3.59
2026-08-22+8.07
2026-08-21+5.71
2026-08-20-4.28
2026-08-19+4.45
2026-08-18-0.77
2026-08-17-0.17
2026-08-16+2.57
2026-08-15+2.76
2026-08-14-1.14
2026-08-13-0.36
2026-08-12+0.95
2026-08-11+1.40
2026-08-10+1.74
2026-08-09+2.68
2026-08-08-3.06
2026-08-07+5.62
2026-08-06+5.06
2026-08-05+3.14
2026-08-04+2.73
2026-08-03+5.59
2026-08-02+2.73

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KOKC, lead day 1-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 0 days-6 to -5 °F: 0 days-5 to -4 °F: 1 day-4 to -3 °F: 1 day-3 to -2 °F: 0 days-2 to -1 °F: 1 day-1 to 0 °F: 5 days0 to 1 °F: 4 days1 to 2 °F: 2 days2 to 3 °F: 5 days3 to 4 °F: 4 days4 to 5 °F: 1 day5 to 6 °F: 4 days6 to 7 °F: 0 days7 to 8 °F: 0 days8 to 9 °F: 1 day9 to 10 °F: 0 daysdashed: P50 |e| 2.73 · P90 |e| 5.59 °F-100+10 °Fn = 29 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
-10.00-9.000
-9.00-8.000
-8.00-7.000
-7.00-6.000
-6.00-5.000
-5.00-4.001
-4.00-3.001
-3.00-2.000
-2.00-1.001
-1.00+0.005
+0.00+1.004
+1.00+2.002
+2.00+3.005
+3.00+4.004
+4.00+5.001
+5.00+6.004
+6.00+7.000
+7.00+8.000
+8.00+9.001
+9.00+10.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08292.67 +1.96

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-02 → 2026-08-30 29
NCEP GFS2026-08-02 → 2026-08-30 29
NCEP GFS2026-08-02 → 2026-08-30 29
NCEP GFS2026-08-02 → 2026-08-30 29

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 29 -1.05 [-2.28, 0.27] no
Aurora (GFS init) 1 -7.42 [-7.42, -7.42] yes
Aurora (IFS init) 2 -7.20 [-7.45, -6.94] yes
FourCastNet v2 (GFS init) 1 -6.15 [-6.15, -6.15] yes
FourCastNet v2 (IFS init) 2 -6.76 [-6.90, -6.62] yes
GraphCast (GFS init) 1 -7.58 [-7.58, -7.58] yes
GraphCast (IFS init) 27 -4.24 [-6.60, -2.06] yes
ECMWF IFS HRES 23 -1.51 [-2.69, -0.13] yes
Pangu-Weather (GFS init) 1 -2.56 [-2.56, -2.56] yes
Pangu-Weather (IFS init) 2 -4.84 [-5.44, -4.24] yes
Persistence (baseline) 29 -0.78 [-1.95, 0.67] no

Cite this page

ShortCastCheck, KOKC gfs lead 1, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KOKC/model/gfs/lead/1/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KOKC (Oklahoma City), model gfs, lead day 1. 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/1/

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

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