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

Houston Bush · NCEP GFS · lead day 1

KIAH · 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, 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
tmax00Zbilinear30d29 1 QC1.24 [0.89, 1.50]1.16-0.36 [-1.19, 0.52]1.56 [1.15, 1.82]52% [37%, 78%]72%93%+0.16+0.232026-08-02 → 2026-08-30
tmax00Zbilinear90d29 1 QC1.24 [0.87, 1.50]1.16-0.36 [-1.22, 0.60]1.56 [1.12, 1.81]52% [34%, 79%]72%93%+0.16+0.232026-08-02 → 2026-08-30
tmax00Zbilinear365d29 1 QC1.24 [0.88, 1.50]1.16-0.36 [-1.27, 0.70]1.56 [1.11, 1.83]52% [36%, 77%]72%93%+0.16+0.232026-08-02 → 2026-08-30
tmax00Zbilinearall29 1 QC1.24 [0.76, 1.49]1.16-0.36 [-1.27, 0.66]1.56 [0.94, 1.83]52% [36%, 86%]72%93%+0.16+0.232026-08-02 → 2026-08-30
tmax00Znearest30d29 1 QC1.28 [1.03, 1.51]1.18-0.38 [-1.19, 0.48]1.64 [1.29, 1.93]55% [43%, 67%]72%90%+0.14+0.212026-08-02 → 2026-08-30
tmax00Znearest90d29 1 QC1.28 [1.02, 1.51]1.18-0.38 [-1.19, 0.53]1.64 [1.25, 1.92]55% [41%, 68%]72%90%+0.14+0.212026-08-02 → 2026-08-30
tmax00Znearest365d29 1 QC1.28 [1.02, 1.54]1.18-0.38 [-1.23, 0.64]1.64 [1.24, 1.93]55% [41%, 70%]72%90%+0.14+0.212026-08-02 → 2026-08-30
tmax00Znearestall29 1 QC1.28 [1.01, 1.51]1.18-0.38 [-1.26, 0.63]1.64 [1.23, 1.92]55% [43%, 70%]72%90%+0.14+0.212026-08-02 → 2026-08-30
tmax12Zbilinear30d29 1 QC1.28 [0.89, 1.68]1.22-0.20 [-1.19, 0.87]1.64 [1.08, 2.08]55% [38%, 76%]79%93%+0.14+0.192026-08-02 → 2026-08-30
tmax12Zbilinear90d29 1 QC1.28 [0.84, 1.71]1.22-0.20 [-1.34, 0.97]1.64 [1.02, 2.10]55% [35%, 79%]79%93%+0.14+0.192026-08-02 → 2026-08-30
tmax12Zbilinear365d29 1 QC1.28 [0.81, 1.72]1.22-0.20 [-1.42, 0.98]1.64 [0.96, 2.11]55% [36%, 80%]79%93%+0.14+0.192026-08-02 → 2026-08-30
tmax12Zbilinearall29 1 QC1.28 [0.78, 1.72]1.22-0.20 [-1.32, 1.02]1.64 [0.90, 2.13]55% [36%, 83%]79%93%+0.14+0.192026-08-02 → 2026-08-30
tmax12Znearest30d29 1 QC1.32 [0.95, 1.69]1.29-0.18 [-1.16, 0.85]1.64 [1.14, 2.05]45% [27%, 67%]79%93%+0.11+0.142026-08-02 → 2026-08-30
tmax12Znearest90d29 1 QC1.32 [0.95, 1.72]1.29-0.18 [-1.27, 0.93]1.64 [1.13, 2.08]45% [25%, 68%]79%93%+0.11+0.142026-08-02 → 2026-08-30
tmax12Znearest365d29 1 QC1.32 [0.91, 1.72]1.29-0.18 [-1.38, 0.94]1.64 [1.09, 2.10]45% [25%, 70%]79%93%+0.11+0.142026-08-02 → 2026-08-30
tmax12Znearestall29 1 QC1.32 [0.93, 1.73]1.29-0.18 [-1.29, 1.02]1.64 [1.11, 2.12]45% [25%, 69%]79%93%+0.11+0.142026-08-02 → 2026-08-30
tmin00Zbilinear30d29 1 QC3.46 [2.50, 4.25]1.64+3.46 [2.50, 4.25]3.95 [3.09, 4.54]17% [4%, 29%]28%38%-0.67+0.222026-08-02 → 2026-08-30
tmin00Zbilinear90d29 1 QC3.46 [2.47, 4.39]1.64+3.46 [2.47, 4.39]3.95 [3.03, 4.66]17% [0%, 30%]28%38%-0.67+0.222026-08-02 → 2026-08-30
tmin00Zbilinear365d29 1 QC3.46 [2.35, 4.45]1.64+3.46 [2.35, 4.45]3.95 [2.93, 4.74]17% [0%, 30%]28%38%-0.67+0.222026-08-02 → 2026-08-30
tmin00Zbilinearall29 1 QC3.46 [2.30, 4.35]1.64+3.46 [2.30, 4.35]3.95 [2.86, 4.64]17% [0%, 30%]28%38%-0.67+0.222026-08-02 → 2026-08-30
tmin00Znearest30d29 1 QC3.63 [2.84, 4.27]1.57+3.63 [2.84, 4.27]4.06 [3.31, 4.58]10% [3%, 18%]28%34%-0.75+0.262026-08-02 → 2026-08-30
tmin00Znearest90d29 1 QC3.63 [2.81, 4.39]1.57+3.63 [2.81, 4.39]4.06 [3.28, 4.66]10% [0%, 21%]28%34%-0.75+0.262026-08-02 → 2026-08-30
tmin00Znearest365d29 1 QC3.63 [2.74, 4.48]1.57+3.63 [2.74, 4.48]4.06 [3.19, 4.74]10% [0%, 20%]28%34%-0.75+0.262026-08-02 → 2026-08-30
tmin00Znearestall29 1 QC3.63 [2.66, 4.34]1.57+3.63 [2.66, 4.34]4.06 [3.07, 4.64]10% [0%, 21%]28%34%-0.75+0.262026-08-02 → 2026-08-30
tmin12Zbilinear30d29 1 QC3.49 [2.59, 4.30]1.55+3.49 [2.59, 4.30]3.95 [3.09, 4.58]17% [7%, 27%]28%31%-0.69+0.272026-08-02 → 2026-08-30
tmin12Zbilinear90d29 1 QC3.49 [2.57, 4.46]1.55+3.49 [2.57, 4.46]3.95 [3.04, 4.70]17% [7%, 28%]28%31%-0.69+0.272026-08-02 → 2026-08-30
tmin12Zbilinear365d29 1 QC3.49 [2.42, 4.48]1.55+3.49 [2.42, 4.48]3.95 [2.93, 4.72]17% [6%, 29%]28%31%-0.69+0.272026-08-02 → 2026-08-30
tmin12Zbilinearall29 1 QC3.49 [2.41, 4.45]1.55+3.49 [2.41, 4.45]3.95 [2.89, 4.74]17% [7%, 29%]28%31%-0.69+0.272026-08-02 → 2026-08-30
tmin12Znearest30d29 1 QC3.69 [2.99, 4.35]1.47+3.67 [2.96, 4.33]4.08 [3.36, 4.62]10% [3%, 18%]24%28%-0.79+0.302026-08-02 → 2026-08-30
tmin12Znearest90d29 1 QC3.69 [2.94, 4.46]1.47+3.67 [2.92, 4.43]4.08 [3.33, 4.71]10% [0%, 21%]24%28%-0.79+0.302026-08-02 → 2026-08-30
tmin12Znearest365d29 1 QC3.69 [2.82, 4.50]1.47+3.67 [2.80, 4.49]4.08 [3.23, 4.73]10% [0%, 20%]24%28%-0.79+0.302026-08-02 → 2026-08-30
tmin12Znearestall29 1 QC3.69 [2.80, 4.46]1.47+3.67 [2.77, 4.44]4.08 [3.19, 4.72]10% [0%, 21%]24%28%-0.79+0.302026-08-02 → 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 KIAH, lead day 1, 00Z bilinear tmax+5+2.50-2.5-52026-08-02: -0.77 °F2026-08-03: +0.75 °F2026-08-04: -0.75 °F2026-08-05: -0.72 °F2026-08-06: +0.03 °F2026-08-07: +0.42 °F2026-08-08: +1.1 °F2026-08-09: +2.46 °F2026-08-10: +3.01 °F2026-08-11: +1.22 °F2026-08-12: -0.46 °F2026-08-13: +0.02 °F2026-08-14: +3.08 °F2026-08-15: -1.79 °F2026-08-16: -1.02 °F2026-08-17: -0.59 °F2026-08-18: -2.44 °F2026-08-19: -0.52 °F2026-08-20: -1.14 °F2026-08-21: -0.75 °F2026-08-22: -2.29 °F2026-08-23: -1.11 °F2026-08-24: -2.4 °F2026-08-25: -0.65 °F2026-08-26: -2.98 °F2026-08-27: +0.13 °F2026-08-28: -2.46 °F2026-08-29: +0.59 °F2026-08-30: -0.38 °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
2026-08-30-0.38
2026-08-29+0.59
2026-08-28-2.46
2026-08-27+0.13
2026-08-26-2.98
2026-08-25-0.65
2026-08-24-2.40
2026-08-23-1.11
2026-08-22-2.29
2026-08-21-0.75
2026-08-20-1.14
2026-08-19-0.52
2026-08-18-2.44
2026-08-17-0.59
2026-08-16-1.02
2026-08-15-1.79
2026-08-14+3.08
2026-08-13+0.02
2026-08-12-0.46
2026-08-11+1.22
2026-08-10+3.01
2026-08-09+2.46
2026-08-08+1.10
2026-08-07+0.42
2026-08-06+0.03
2026-08-05-0.72
2026-08-04-0.75
2026-08-03+0.75
2026-08-02-0.77

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KIAH, lead day 1-5 to -4.5 °F: 0 days-4.5 to -4 °F: 0 days-4 to -3.5 °F: 0 days-3.5 to -3 °F: 0 days-3 to -2.5 °F: 1 day-2.5 to -2 °F: 4 days-2 to -1.5 °F: 1 day-1.5 to -1 °F: 3 days-1 to -0.5 °F: 7 days-0.5 to 0 °F: 2 days0 to 0.5 °F: 4 days0.5 to 1 °F: 2 days1 to 1.5 °F: 2 days1.5 to 2 °F: 0 days2 to 2.5 °F: 1 day2.5 to 3 °F: 0 days3 to 3.5 °F: 2 days3.5 to 4 °F: 0 days4 to 4.5 °F: 0 days4.5 to 5 °F: 0 daysdashed: P50 |e| 0.77 · P90 |e| 2.56 °F-50+5 °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
-5.00-4.500
-4.50-4.000
-4.00-3.500
-3.50-3.000
-3.00-2.501
-2.50-2.004
-2.00-1.501
-1.50-1.003
-1.00-0.507
-0.50+0.002
+0.00+0.504
+0.50+1.002
+1.00+1.502
+1.50+2.000
+2.00+2.501
+2.50+3.000
+3.00+3.502
+3.50+4.000
+4.00+4.500
+4.50+5.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08291.24 -0.36

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 -2.51 [-3.36, -1.65] yes
Aurora (GFS init) 1 -6.00 [-6.00, -6.00] yes
Aurora (IFS init) 2 -5.77 [-6.43, -5.12] yes
FourCastNet v2 (GFS init) 1 -3.01 [-3.01, -3.01] yes
FourCastNet v2 (IFS init) 2 -3.22 [-3.28, -3.17] yes
GraphCast (GFS init) 1 -5.17 [-5.17, -5.17] yes
GraphCast (IFS init) 27 -4.96 [-5.73, -4.48] yes
ECMWF IFS HRES 23 -2.45 [-3.47, -1.30] yes
Pangu-Weather (GFS init) 1 -1.76 [-1.76, -1.76] yes
Pangu-Weather (IFS init) 2 -3.08 [-3.11, -3.05] yes
Persistence (baseline) 29 -0.24 [-0.79, 0.17] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KIAH (Houston Bush), 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/KIAH/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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