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

Austin Bergstrom · NCEP GFS · lead day 4

KAUS · gfs · 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, 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
tmax00Zbilinear30d26 1 QC1.87 [1.02, 2.86]1.87-1.22 [-2.36, -0.22]2.50 [1.51, 3.28]38% [18%, 60%]65%69%+0.05+0.062026-08-05 → 2026-08-30
tmax00Zbilinear90d26 1 QC1.87 [0.98, 3.04]1.87-1.22 [-2.49, -0.21]2.50 [1.42, 3.39]38% [14%, 60%]65%69%+0.05+0.062026-08-05 → 2026-08-30
tmax00Zbilinear365d26 1 QC1.87 [0.85, 3.11]1.87-1.22 [-2.58, -0.07]2.50 [1.27, 3.45]38% [11%, 63%]65%69%+0.05+0.062026-08-05 → 2026-08-30
tmax00Zbilinearall26 1 QC1.87 [0.90, 3.07]1.87-1.22 [-2.59, -0.14]2.50 [1.31, 3.44]38% [14%, 62%]65%69%+0.05+0.062026-08-05 → 2026-08-30
tmax00Znearest30d26 1 QC1.93 [1.03, 3.07]1.96-1.08 [-2.25, -0.10]2.51 [1.41, 3.41]46% [12%, 73%]65%73%+0.02+0.012026-08-05 → 2026-08-30
tmax00Znearest90d26 1 QC1.93 [0.99, 3.31]1.96-1.08 [-2.35, -0.07]2.51 [1.35, 3.60]46% [4%, 76%]65%73%+0.02+0.012026-08-05 → 2026-08-30
tmax00Znearest365d26 1 QC1.93 [0.89, 3.37]1.96-1.08 [-2.47, 0.05]2.51 [1.17, 3.63]46% [0%, 79%]65%73%+0.02+0.012026-08-05 → 2026-08-30
tmax00Znearestall26 1 QC1.93 [0.94, 3.36]1.96-1.08 [-2.49, 0.02]2.51 [1.23, 3.62]46% [0%, 78%]65%73%+0.02+0.012026-08-05 → 2026-08-30
tmax12Zbilinear30d26 1 QC1.51 [1.15, 1.92]1.37-0.91 [-1.70, -0.17]1.95 [1.41, 2.37]50% [36%, 62%]77%88%+0.23+0.312026-08-05 → 2026-08-30
tmax12Zbilinear90d26 1 QC1.51 [1.11, 1.97]1.37-0.91 [-1.81, -0.17]1.95 [1.31, 2.40]50% [33%, 63%]77%88%+0.23+0.312026-08-05 → 2026-08-30
tmax12Zbilinear365d26 1 QC1.51 [1.13, 1.98]1.37-0.91 [-1.85, -0.13]1.95 [1.35, 2.40]50% [33%, 67%]77%88%+0.23+0.312026-08-05 → 2026-08-30
tmax12Zbilinearall26 1 QC1.51 [1.14, 2.00]1.37-0.91 [-1.85, -0.13]1.95 [1.35, 2.41]50% [33%, 65%]77%88%+0.23+0.312026-08-05 → 2026-08-30
tmax12Znearest30d26 1 QC1.55 [1.17, 2.02]1.52-0.57 [-1.25, 0.12]2.01 [1.51, 2.45]46% [26%, 60%]77%85%+0.21+0.232026-08-05 → 2026-08-30
tmax12Znearest90d26 1 QC1.55 [1.17, 2.11]1.52-0.57 [-1.30, 0.17]2.01 [1.44, 2.48]46% [21%, 62%]77%85%+0.21+0.232026-08-05 → 2026-08-30
tmax12Znearest365d26 1 QC1.55 [1.17, 2.09]1.52-0.57 [-1.30, 0.19]2.01 [1.44, 2.49]46% [24%, 62%]77%85%+0.21+0.232026-08-05 → 2026-08-30
tmax12Znearestall26 1 QC1.55 [1.17, 2.09]1.52-0.57 [-1.37, 0.21]2.01 [1.47, 2.51]46% [17%, 62%]77%85%+0.21+0.232026-08-05 → 2026-08-30
tmin00Zbilinear30d26 1 QC3.28 [2.21, 4.35]2.48+2.68 [0.85, 4.31]4.10 [2.84, 5.01]23% [5%, 43%]35%58%-0.03+0.222026-08-05 → 2026-08-30
tmin00Zbilinear90d26 1 QC3.28 [2.05, 4.47]2.48+2.68 [0.77, 4.47]4.10 [2.59, 5.10]23% [0%, 44%]35%58%-0.03+0.222026-08-05 → 2026-08-30
tmin00Zbilinear365d26 1 QC3.28 [2.03, 4.76]2.48+2.68 [0.73, 4.76]4.10 [2.55, 5.38]23% [0%, 46%]35%58%-0.03+0.222026-08-05 → 2026-08-30
tmin00Zbilinearall26 1 QC3.28 [1.99, 4.54]2.48+2.68 [0.71, 4.54]4.10 [2.54, 5.17]23% [0%, 46%]35%58%-0.03+0.222026-08-05 → 2026-08-30
tmin00Znearest30d26 1 QC4.17 [2.67, 5.61]2.62+3.82 [1.81, 5.60]5.03 [3.48, 6.16]15% [0%, 34%]19%42%-0.31+0.182026-08-05 → 2026-08-30
tmin00Znearest90d26 1 QC4.17 [2.54, 5.77]2.62+3.82 [1.71, 5.77]5.03 [3.27, 6.27]15% [0%, 33%]19%42%-0.31+0.182026-08-05 → 2026-08-30
tmin00Znearest365d26 1 QC4.17 [2.52, 6.06]2.62+3.82 [1.67, 6.06]5.03 [3.25, 6.53]15% [0%, 36%]19%42%-0.31+0.182026-08-05 → 2026-08-30
tmin00Znearestall26 1 QC4.17 [2.45, 5.83]2.62+3.82 [1.65, 5.83]5.03 [3.25, 6.34]15% [0%, 35%]19%42%-0.31+0.182026-08-05 → 2026-08-30
tmin12Zbilinear30d26 1 QC3.30 [2.27, 4.38]2.60+2.75 [0.89, 4.37]4.21 [2.86, 5.22]27% [12%, 41%]38%46%-0.04+0.192026-08-05 → 2026-08-30
tmin12Zbilinear90d26 1 QC3.30 [2.18, 4.56]2.60+2.75 [0.90, 4.56]4.21 [2.70, 5.35]27% [9%, 40%]38%46%-0.04+0.192026-08-05 → 2026-08-30
tmin12Zbilinear365d26 1 QC3.30 [2.11, 4.85]2.60+2.75 [0.83, 4.85]4.21 [2.63, 5.64]27% [8%, 43%]38%46%-0.04+0.192026-08-05 → 2026-08-30
tmin12Zbilinearall26 1 QC3.30 [2.11, 4.61]2.60+2.75 [0.77, 4.61]4.21 [2.65, 5.44]27% [8%, 43%]38%46%-0.04+0.192026-08-05 → 2026-08-30
tmin12Znearest30d26 1 QC4.23 [2.71, 5.67]2.73+3.92 [1.88, 5.67]5.13 [3.55, 6.32]8% [0%, 20%]27%42%-0.33+0.152026-08-05 → 2026-08-30
tmin12Znearest90d26 1 QC4.23 [2.60, 5.87]2.73+3.92 [1.84, 5.87]5.13 [3.39, 6.47]8% [0%, 20%]27%42%-0.33+0.152026-08-05 → 2026-08-30
tmin12Znearest365d26 1 QC4.23 [2.58, 6.19]2.73+3.92 [1.76, 6.19]5.13 [3.35, 6.80]8% [0%, 22%]27%42%-0.33+0.152026-08-05 → 2026-08-30
tmin12Znearestall26 1 QC4.23 [2.55, 5.88]2.73+3.92 [1.72, 5.88]5.13 [3.36, 6.54]8% [0%, 21%]27%42%-0.33+0.152026-08-05 → 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 NCEP GFS at KAUS, lead day 4, 00Z bilinear tmax+10+50-5-102026-08-05: -0.31 °F2026-08-06: -3.99 °F2026-08-07: -4.01 °F2026-08-08: -4.03 °F2026-08-09: -4.34 °F2026-08-10: -1.03 °F2026-08-11: +0.31 °F2026-08-12: +0.25 °F2026-08-13: -1.23 °F2026-08-14: +0.02 °F2026-08-15: +0.31 °F2026-08-16: +1.31 °F2026-08-17: -0.63 °F2026-08-18: +0.09 °F2026-08-19: +1.13 °F2026-08-20: +0.94 °F2026-08-21: +0.19 °F2026-08-22: -3.92 °F2026-08-23: -1.62 °F2026-08-24: -1.52 °F2026-08-25: -0.53 °F2026-08-26: +1.37 °F2026-08-27: -5.69 °F2026-08-28: -3.68 °F2026-08-29: +2.56 °F2026-08-30: -3.65 °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
2026-08-30-3.65
2026-08-29+2.56
2026-08-28-3.68
2026-08-27-5.69
2026-08-26+1.37
2026-08-25-0.53
2026-08-24-1.52
2026-08-23-1.62
2026-08-22-3.92
2026-08-21+0.19
2026-08-20+0.94
2026-08-19+1.13
2026-08-18+0.09
2026-08-17-0.63
2026-08-16+1.31
2026-08-15+0.31
2026-08-14+0.02
2026-08-13-1.23
2026-08-12+0.25
2026-08-11+0.31
2026-08-10-1.03
2026-08-09-4.34
2026-08-08-4.03
2026-08-07-4.01
2026-08-06-3.99
2026-08-05-0.31

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KAUS, lead day 4-10 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: 1 day-5 to -4 °F: 3 days-4 to -3 °F: 4 days-3 to -2 °F: 0 days-2 to -1 °F: 4 days-1 to 0 °F: 3 days0 to 1 °F: 7 days1 to 2 °F: 3 days2 to 3 °F: 1 day3 to 4 °F: 0 days4 to 5 °F: 0 days5 to 6 °F: 0 days6 to 7 °F: 0 days7 to 8 °F: 0 days8 to 9 °F: 0 days9 to 10 °F: 0 daysdashed: P50 |e| 1.27 · P90 |e| 4.02 °F-100+10 °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
-10.00-9.000
-9.00-8.000
-8.00-7.000
-7.00-6.000
-6.00-5.001
-5.00-4.003
-4.00-3.004
-3.00-2.000
-2.00-1.004
-1.00+0.003
+0.00+1.007
+1.00+2.003
+2.00+3.001
+3.00+4.000
+4.00+5.000
+5.00+6.000
+6.00+7.000
+7.00+8.000
+8.00+9.000
+9.00+10.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08261.87 -1.22

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-05 → 2026-08-30 26
NCEP GFS2026-08-05 → 2026-08-30 26
NCEP GFS2026-08-05 → 2026-08-30 26
NCEP GFS2026-08-05 → 2026-08-30 26

Compared with other models

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

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 26 -3.00 [-3.94, -1.35] yes
GraphCast (IFS init) 25 -5.41 [-7.10, -3.12] yes
ECMWF IFS HRES 20 -2.28 [-3.29, -1.13] yes
Persistence (baseline) 26 -0.09 [-0.84, 0.86] no

Cite this page

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

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