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

Houston Bush · NCEP GFS · lead day 0

KIAH · gfs · lead 0

Target day = initialization date + 0 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
tmax00Zbilinear30d30 1 QC1.43 [0.98, 1.95]1.32-0.49 [-1.46, 0.54]2.00 [1.15, 2.74]47% [37%, 57%]80%90%——2026-08-01 → 2026-08-30
tmax00Zbilinear90d30 1 QC1.43 [0.95, 2.02]1.32-0.49 [-1.72, 0.67]2.00 [1.10, 2.85]47% [33%, 60%]80%90%——2026-08-01 → 2026-08-30
tmax00Zbilinear365d30 1 QC1.43 [0.94, 2.06]1.32-0.49 [-1.87, 0.64]2.00 [1.06, 2.89]47% [35%, 60%]80%90%——2026-08-01 → 2026-08-30
tmax00Zbilinearall30 1 QC1.43 [0.93, 2.00]1.32-0.49 [-1.67, 0.73]2.00 [1.07, 2.81]47% [33%, 61%]80%90%——2026-08-01 → 2026-08-30
tmax00Znearest30d30 1 QC1.38 [0.92, 1.90]1.30-0.52 [-1.41, 0.41]1.97 [1.14, 2.69]50% [40%, 60%]77%93%——2026-08-01 → 2026-08-30
tmax00Znearest90d30 1 QC1.38 [0.95, 1.94]1.30-0.52 [-1.61, 0.53]1.97 [1.17, 2.77]50% [37%, 61%]77%93%——2026-08-01 → 2026-08-30
tmax00Znearest365d30 1 QC1.38 [0.90, 1.97]1.30-0.52 [-1.77, 0.51]1.97 [1.09, 2.80]50% [38%, 62%]77%93%——2026-08-01 → 2026-08-30
tmax00Znearestall30 1 QC1.38 [0.92, 1.94]1.30-0.52 [-1.58, 0.58]1.97 [1.13, 2.74]50% [37%, 62%]77%93%——2026-08-01 → 2026-08-30
tmin00Zbilinear30d30 1 QC3.57 [2.78, 4.36]1.52+3.57 [2.78, 4.36]4.02 [3.18, 4.73]10% [0%, 23%]27%33%——2026-08-01 → 2026-08-30
tmin00Zbilinear90d30 1 QC3.57 [2.66, 4.49]1.52+3.57 [2.66, 4.49]4.02 [3.10, 4.79]10% [0%, 27%]27%33%——2026-08-01 → 2026-08-30
tmin00Zbilinear365d30 1 QC3.57 [2.55, 4.62]1.52+3.57 [2.55, 4.62]4.02 [3.02, 4.92]10% [0%, 27%]27%33%——2026-08-01 → 2026-08-30
tmin00Zbilinearall30 1 QC3.57 [2.51, 4.50]1.52+3.57 [2.51, 4.50]4.02 [2.94, 4.88]10% [0%, 30%]27%33%——2026-08-01 → 2026-08-30
tmin00Znearest30d30 1 QC3.70 [3.07, 4.35]1.41+3.67 [3.01, 4.34]4.08 [3.40, 4.68]10% [0%, 23%]23%30%——2026-08-01 → 2026-08-30
tmin00Znearest90d30 1 QC3.70 [2.89, 4.45]1.41+3.67 [2.83, 4.45]4.08 [3.26, 4.74]10% [0%, 27%]23%30%——2026-08-01 → 2026-08-30
tmin00Znearest365d30 1 QC3.70 [2.86, 4.56]1.41+3.67 [2.76, 4.56]4.08 [3.19, 4.84]10% [0%, 27%]23%30%——2026-08-01 → 2026-08-30
tmin00Znearestall30 1 QC3.70 [2.77, 4.49]1.41+3.67 [2.70, 4.49]4.08 [3.10, 4.78]10% [0%, 30%]23%30%——2026-08-01 → 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 0, 00Z bilinear tmax+10+50-5-102026-08-01: +1.64 °F2026-08-02: -1.05 °F2026-08-03: +0.03 °F2026-08-04: -1.24 °F2026-08-05: -1.45 °F2026-08-06: +0.97 °F2026-08-07: +0.62 °F2026-08-08: +0.84 °F2026-08-09: +1.83 °F2026-08-10: +4.69 °F2026-08-11: +2.06 °F2026-08-12: -0.26 °F2026-08-13: +0.87 °F2026-08-14: -1.14 °F2026-08-15: -1.13 °F2026-08-16: -1.12 °F2026-08-17: -0.51 °F2026-08-18: -1.48 °F2026-08-19: +0.17 °F2026-08-20: -0.66 °F2026-08-21: -0.79 °F2026-08-22: -2.21 °F2026-08-23: +0.38 °F2026-08-24: -2.63 °F2026-08-25: -0.41 °F2026-08-26: -1.33 °F2026-08-27: -6.9 °F2026-08-28: -3.18 °F2026-08-29: -0.89 °F2026-08-30: -0.46 °F2026-08-012026-08-30°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 (30 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-0.46
2026-08-29-0.89
2026-08-28-3.18
2026-08-27-6.90
2026-08-26-1.33
2026-08-25-0.41
2026-08-24-2.63
2026-08-23+0.38
2026-08-22-2.21
2026-08-21-0.79
2026-08-20-0.66
2026-08-19+0.17
2026-08-18-1.48
2026-08-17-0.51
2026-08-16-1.12
2026-08-15-1.13
2026-08-14-1.14
2026-08-13+0.87
2026-08-12-0.26
2026-08-11+2.06
2026-08-10+4.69
2026-08-09+1.83
2026-08-08+0.84
2026-08-07+0.62
2026-08-06+0.97
2026-08-05-1.45
2026-08-04-1.24
2026-08-03+0.03
2026-08-02-1.05
2026-08-01+1.64

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KIAH, lead day 0-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 1 day-6 to -5 °F: 0 days-5 to -4 °F: 0 days-4 to -3 °F: 1 day-3 to -2 °F: 2 days-2 to -1 °F: 8 days-1 to 0 °F: 7 days0 to 1 °F: 7 days1 to 2 °F: 2 days2 to 3 °F: 1 day3 to 4 °F: 0 days4 to 5 °F: 1 day5 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| 1.08 · P90 |e| 2.68 °F-100+10 °Fn = 30 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
-7.00-6.001
-6.00-5.000
-5.00-4.000
-4.00-3.001
-3.00-2.002
-2.00-1.008
-1.00+0.007
+0.00+1.007
+1.00+2.002
+2.00+3.001
+3.00+4.000
+4.00+5.001
+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
2026-08301.43 -0.49

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-01 → 2026-08-30 30
NCEP GFS2026-08-01 → 2026-08-30 30

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 30 -2.03 [-2.76, -1.14] yes
Aurora (GFS init) 2 -4.67 [-5.10, -4.25] yes
Aurora (IFS init) 3 -4.81 [-5.21, -4.01] yes
FourCastNet v2 (GFS init) 2 -3.20 [-3.25, -3.15] yes
FourCastNet v2 (IFS init) 3 -2.97 [-3.71, -1.48] yes
GraphCast (GFS init) 2 -3.41 [-3.51, -3.30] yes
GraphCast (IFS init) 28 -4.31 [-4.68, -3.89] yes
ECMWF IFS HRES 24 -2.27 [-3.06, -1.17] yes
Pangu-Weather (GFS init) 2 -1.82 [-2.22, -1.43] yes
Pangu-Weather (IFS init) 3 -1.79 [-2.32, -0.73] yes

Cite this page

ShortCastCheck, KIAH gfs lead 0, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KIAH/model/gfs/lead/0/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KIAH (Houston Bush), model gfs, lead day 0. 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/0/

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

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