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

Austin Bergstrom · NCEP GFS · lead day 8

KAUS · 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, 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
tmax00Zbilinear30d22 1 QC2.31 [1.17, 3.68]2.27-1.06 [-2.69, 0.25]3.40 [1.45, 4.94]23% [6%, 41%]64%73%+0.12+0.002026-08-09 → 2026-08-30
tmax00Zbilinear90d22 1 QC2.31 [1.14, 3.72]2.27-1.06 [-2.87, 0.36]3.40 [1.35, 5.01]23% [4%, 43%]64%73%+0.12+0.002026-08-09 → 2026-08-30
tmax00Zbilinear365d22 1 QC2.31 [1.13, 3.88]2.27-1.06 [-2.99, 0.36]3.40 [1.36, 5.24]23% [0%, 44%]64%73%+0.12+0.002026-08-09 → 2026-08-30
tmax00Zbilinearall22 1 QC2.31 [1.12, 3.89]2.27-1.06 [-2.94, 0.40]3.40 [1.35, 5.32]23% [0%, 43%]64%73%+0.12+0.002026-08-09 → 2026-08-30
tmax00Znearest30d22 1 QC2.34 [1.23, 3.65]2.35-0.91 [-2.63, 0.42]3.47 [1.47, 5.07]32% [11%, 60%]64%68%+0.11-0.032026-08-09 → 2026-08-30
tmax00Znearest90d22 1 QC2.34 [1.07, 3.67]2.35-0.91 [-2.78, 0.47]3.47 [1.18, 5.11]32% [9%, 71%]64%68%+0.11-0.032026-08-09 → 2026-08-30
tmax00Znearest365d22 1 QC2.34 [1.06, 3.87]2.35-0.91 [-2.86, 0.50]3.47 [1.18, 5.41]32% [8%, 69%]64%68%+0.11-0.032026-08-09 → 2026-08-30
tmax00Znearestall22 1 QC2.34 [1.06, 3.86]2.35-0.91 [-2.85, 0.50]3.47 [1.19, 5.38]32% [8%, 67%]64%68%+0.11-0.032026-08-09 → 2026-08-30
tmax12Zbilinear30d22 1 QC1.87 [0.72, 3.05]1.96-0.54 [-1.71, 0.61]3.02 [0.97, 4.33]59% [43%, 74%]68%86%+0.29+0.142026-08-09 → 2026-08-30
tmax12Zbilinear90d22 1 QC1.87 [0.56, 3.07]1.96-0.54 [-1.81, 0.82]3.02 [0.72, 4.36]59% [42%, 75%]68%86%+0.29+0.142026-08-09 → 2026-08-30
tmax12Zbilinear365d22 1 QC1.87 [0.55, 3.22]1.96-0.54 [-1.95, 0.99]3.02 [0.70, 4.59]59% [41%, 75%]68%86%+0.29+0.142026-08-09 → 2026-08-30
tmax12Zbilinearall22 1 QC1.87 [0.55, 3.35]1.96-0.54 [-2.01, 0.82]3.02 [0.70, 4.55]59% [37%, 75%]68%86%+0.29+0.142026-08-09 → 2026-08-30
tmax12Znearest30d22 1 QC1.78 [0.66, 2.86]1.89-0.40 [-1.56, 0.73]2.87 [0.95, 4.10]59% [36%, 85%]73%82%+0.33+0.172026-08-09 → 2026-08-30
tmax12Znearest90d22 1 QC1.78 [0.53, 2.88]1.89-0.40 [-1.69, 0.90]2.87 [0.72, 4.11]59% [33%, 89%]73%82%+0.33+0.172026-08-09 → 2026-08-30
tmax12Znearest365d22 1 QC1.78 [0.46, 3.04]1.89-0.40 [-1.79, 0.98]2.87 [0.64, 4.33]59% [29%, 90%]73%82%+0.33+0.172026-08-09 → 2026-08-30
tmax12Znearestall22 1 QC1.78 [0.49, 3.16]1.89-0.40 [-1.75, 0.91]2.87 [0.65, 4.28]59% [29%, 92%]73%82%+0.33+0.172026-08-09 → 2026-08-30
tmin00Zbilinear30d22 1 QC2.99 [1.96, 3.90]2.34+2.21 [0.41, 3.73]3.51 [2.46, 4.24]14% [0%, 33%]41%59%-0.04+0.192026-08-09 → 2026-08-30
tmin00Zbilinear90d22 1 QC2.99 [1.52, 3.86]2.34+2.21 [0.24, 3.80]3.51 [1.94, 4.24]14% [0%, 39%]41%59%-0.04+0.192026-08-09 → 2026-08-30
tmin00Zbilinear365d22 1 QC2.99 [1.52, 3.94]2.34+2.21 [0.20, 3.92]3.51 [1.94, 4.31]14% [0%, 36%]41%59%-0.04+0.192026-08-09 → 2026-08-30
tmin00Zbilinearall22 1 QC2.99 [1.52, 4.00]2.34+2.21 [0.18, 3.95]3.51 [1.91, 4.34]14% [0%, 34%]41%59%-0.04+0.192026-08-09 → 2026-08-30
tmin00Znearest30d22 1 QC3.73 [2.23, 5.04]2.51+3.29 [1.27, 4.99]4.41 [2.96, 5.39]18% [0%, 35%]27%41%-0.30+0.132026-08-09 → 2026-08-30
tmin00Znearest90d22 1 QC3.73 [1.99, 5.10]2.51+3.29 [1.09, 5.09]4.41 [2.55, 5.41]18% [0%, 36%]27%41%-0.30+0.132026-08-09 → 2026-08-30
tmin00Znearest365d22 1 QC3.73 [2.02, 5.20]2.51+3.29 [1.06, 5.20]4.41 [2.40, 5.48]18% [0%, 38%]27%41%-0.30+0.132026-08-09 → 2026-08-30
tmin00Znearestall22 1 QC3.73 [1.98, 5.20]2.51+3.29 [1.03, 5.20]4.41 [2.39, 5.48]18% [0%, 38%]27%41%-0.30+0.132026-08-09 → 2026-08-30
tmin12Zbilinear30d22 1 QC3.51 [2.27, 4.97]2.59+2.83 [0.94, 4.81]4.41 [2.71, 6.00]18% [3%, 36%]32%55%-0.22+0.102026-08-09 → 2026-08-30
tmin12Zbilinear90d22 1 QC3.51 [2.14, 5.08]2.59+2.83 [0.79, 5.04]4.41 [2.62, 6.15]18% [0%, 43%]32%55%-0.22+0.102026-08-09 → 2026-08-30
tmin12Zbilinear365d22 1 QC3.51 [2.14, 5.18]2.59+2.83 [0.79, 5.11]4.41 [2.66, 6.24]18% [0%, 42%]32%55%-0.22+0.102026-08-09 → 2026-08-30
tmin12Zbilinearall22 1 QC3.51 [2.11, 5.10]2.59+2.83 [0.70, 5.08]4.41 [2.56, 6.24]18% [0%, 43%]32%55%-0.22+0.102026-08-09 → 2026-08-30
tmin12Znearest30d22 1 QC4.34 [2.68, 6.21]2.79+3.92 [1.77, 6.17]5.37 [3.21, 7.27]9% [0%, 15%]32%36%-0.51+0.032026-08-09 → 2026-08-30
tmin12Znearest90d22 1 QC4.34 [2.55, 6.38]2.79+3.92 [1.53, 6.38]5.37 [3.04, 7.42]9% [0%, 15%]32%36%-0.51+0.032026-08-09 → 2026-08-30
tmin12Znearest365d22 1 QC4.34 [2.58, 6.49]2.79+3.92 [1.57, 6.49]5.37 [3.11, 7.53]9% [0%, 14%]32%36%-0.51+0.032026-08-09 → 2026-08-30
tmin12Znearestall22 1 QC4.34 [2.54, 6.42]2.79+3.92 [1.51, 6.41]5.37 [3.02, 7.48]9% [0%, 14%]32%36%-0.51+0.032026-08-09 → 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 KAUS, lead day 8, 00Z bilinear tmax+20+100-10-202026-08-09: -0.39 °F2026-08-10: -2.37 °F2026-08-11: -1.06 °F2026-08-12: -0.76 °F2026-08-13: +1.15 °F2026-08-14: +1.99 °F2026-08-15: +0.29 °F2026-08-16: -0.07 °F2026-08-17: -1.12 °F2026-08-18: -3.28 °F2026-08-19: +1.2 °F2026-08-20: +1.14 °F2026-08-21: -1.77 °F2026-08-22: -11.07 °F2026-08-23: -7.16 °F2026-08-24: -4.29 °F2026-08-25: -0.32 °F2026-08-26: +3.35 °F2026-08-27: -1.06 °F2026-08-28: +1.15 °F2026-08-29: +3.56 °F2026-08-30: -2.39 °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
2026-08-30-2.39
2026-08-29+3.56
2026-08-28+1.15
2026-08-27-1.06
2026-08-26+3.35
2026-08-25-0.32
2026-08-24-4.29
2026-08-23-7.16
2026-08-22-11.07
2026-08-21-1.77
2026-08-20+1.14
2026-08-19+1.20
2026-08-18-3.28
2026-08-17-1.12
2026-08-16-0.07
2026-08-15+0.29
2026-08-14+1.99
2026-08-13+1.15
2026-08-12-0.76
2026-08-11-1.06
2026-08-10-2.37
2026-08-09-0.39

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KAUS, 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: 0 days-12 to -10 °F: 1 day-10 to -8 °F: 0 days-8 to -6 °F: 1 day-6 to -4 °F: 1 day-4 to -2 °F: 3 days-2 to 0 °F: 8 days0 to 2 °F: 6 days2 to 4 °F: 2 days4 to 6 °F: 0 days6 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| 1.17 · P90 |e| 4.22 °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
-14.00-12.000
-12.00-10.001
-10.00-8.000
-8.00-6.001
-6.00-4.001
-4.00-2.003
-2.00+0.008
+0.00+2.006
+2.00+4.002
+4.00+6.000
+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
2026-08222.31 -1.06

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 -2.36 [-3.40, -1.07] yes
GraphCast (IFS init) 22 -5.12 [-6.14, -4.09] yes
ECMWF IFS HRES 17 -1.53 [-3.78, -0.19] yes
Persistence (baseline) 22 -0.32 [-1.57, 0.89] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KAUS (Austin Bergstrom), 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/KAUS/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