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 7

KIAH · gfs · lead 7

Target day = initialization date + 7 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
tmax00Zbilinear30d23 1 QC2.29 [1.52, 3.02]2.17-0.92 [-2.58, 0.85]2.87 [1.96, 3.59]30% [8%, 52%]52%70%+0.31+0.352026-08-08 → 2026-08-30
tmax00Zbilinear90d23 1 QC2.29 [1.50, 3.13]2.17-0.92 [-2.71, 1.27]2.87 [1.86, 3.67]30% [0%, 52%]52%70%+0.31+0.352026-08-08 → 2026-08-30
tmax00Zbilinear365d23 1 QC2.29 [1.35, 3.15]2.17-0.92 [-2.75, 1.19]2.87 [1.79, 3.65]30% [0%, 54%]52%70%+0.31+0.352026-08-08 → 2026-08-30
tmax00Zbilinearall23 1 QC2.29 [1.41, 3.11]2.17-0.92 [-2.79, 1.25]2.87 [1.82, 3.62]30% [0%, 55%]52%70%+0.31+0.352026-08-08 → 2026-08-30
tmax00Znearest30d23 1 QC2.45 [1.57, 3.32]2.30-1.10 [-2.79, 0.58]3.09 [2.05, 4.00]30% [5%, 55%]48%70%+0.27+0.312026-08-08 → 2026-08-30
tmax00Znearest90d23 1 QC2.45 [1.51, 3.39]2.30-1.10 [-2.98, 0.76]3.09 [1.89, 4.04]30% [0%, 57%]48%70%+0.27+0.312026-08-08 → 2026-08-30
tmax00Znearest365d23 1 QC2.45 [1.41, 3.37]2.30-1.10 [-3.03, 0.77]3.09 [1.81, 4.04]30% [0%, 57%]48%70%+0.27+0.312026-08-08 → 2026-08-30
tmax00Znearestall23 1 QC2.45 [1.44, 3.38]2.30-1.10 [-3.04, 0.83]3.09 [1.76, 4.02]30% [0%, 57%]48%70%+0.27+0.312026-08-08 → 2026-08-30
tmax12Zbilinear30d23 1 QC2.40 [1.39, 3.36]2.30-0.61 [-2.20, 1.02]3.37 [1.87, 4.28]39% [20%, 60%]57%70%+0.28+0.312026-08-08 → 2026-08-30
tmax12Zbilinear90d23 1 QC2.40 [1.24, 3.69]2.30-0.61 [-2.29, 1.26]3.37 [1.66, 4.49]39% [12%, 64%]57%70%+0.28+0.312026-08-08 → 2026-08-30
tmax12Zbilinear365d23 1 QC2.40 [1.21, 3.72]2.30-0.61 [-2.51, 1.39]3.37 [1.60, 4.58]39% [11%, 63%]57%70%+0.28+0.312026-08-08 → 2026-08-30
tmax12Zbilinearall23 1 QC2.40 [1.24, 3.81]2.30-0.61 [-2.48, 1.33]3.37 [1.66, 4.58]39% [10%, 64%]57%70%+0.28+0.312026-08-08 → 2026-08-30
tmax12Znearest30d23 1 QC2.50 [1.43, 3.59]2.42-0.85 [-2.50, 0.77]3.69 [2.11, 4.76]52% [29%, 72%]57%65%+0.25+0.272026-08-08 → 2026-08-30
tmax12Znearest90d23 1 QC2.50 [1.24, 3.91]2.42-0.85 [-2.69, 0.92]3.69 [1.73, 4.99]52% [25%, 75%]57%65%+0.25+0.272026-08-08 → 2026-08-30
tmax12Znearest365d23 1 QC2.50 [1.21, 3.93]2.42-0.85 [-2.81, 0.97]3.69 [1.70, 5.01]52% [23%, 75%]57%65%+0.25+0.272026-08-08 → 2026-08-30
tmax12Znearestall23 1 QC2.50 [1.21, 4.01]2.42-0.85 [-2.76, 0.92]3.69 [1.70, 5.11]52% [20%, 75%]57%65%+0.25+0.272026-08-08 → 2026-08-30
tmin00Zbilinear30d23 1 QC3.48 [2.26, 4.77]2.29+3.10 [1.54, 4.67]4.11 [2.91, 5.06]22% [7%, 35%]35%43%+0.01+0.352026-08-08 → 2026-08-30
tmin00Zbilinear90d23 1 QC3.48 [2.24, 5.04]2.29+3.10 [1.53, 5.01]4.11 [2.89, 5.27]22% [0%, 36%]35%43%+0.01+0.352026-08-08 → 2026-08-30
tmin00Zbilinear365d23 1 QC3.48 [2.07, 4.94]2.29+3.10 [1.17, 4.89]4.11 [2.66, 5.16]22% [0%, 38%]35%43%+0.01+0.352026-08-08 → 2026-08-30
tmin00Zbilinearall23 1 QC3.48 [1.92, 5.01]2.29+3.10 [1.07, 5.01]4.11 [2.44, 5.20]22% [0%, 40%]35%43%+0.01+0.352026-08-08 → 2026-08-30
tmin00Znearest30d23 1 QC3.49 [2.31, 4.69]2.22+3.14 [1.63, 4.63]4.09 [2.90, 4.99]22% [7%, 35%]30%43%+0.01+0.372026-08-08 → 2026-08-30
tmin00Znearest90d23 1 QC3.49 [2.29, 4.99]2.22+3.14 [1.63, 4.96]4.09 [2.90, 5.20]22% [0%, 36%]30%43%+0.01+0.372026-08-08 → 2026-08-30
tmin00Znearest365d23 1 QC3.49 [2.11, 4.85]2.22+3.14 [1.30, 4.81]4.09 [2.69, 5.09]22% [0%, 38%]30%43%+0.01+0.372026-08-08 → 2026-08-30
tmin00Znearestall23 1 QC3.49 [1.95, 4.93]2.22+3.14 [1.18, 4.93]4.09 [2.47, 5.13]22% [0%, 40%]30%43%+0.01+0.372026-08-08 → 2026-08-30
tmin12Zbilinear30d23 1 QC3.55 [2.41, 4.74]2.22+3.22 [1.88, 4.53]4.16 [3.09, 5.12]13% [0%, 25%]26%48%-0.01+0.372026-08-08 → 2026-08-30
tmin12Zbilinear90d23 1 QC3.55 [2.36, 4.95]2.22+3.22 [1.81, 4.73]4.16 [3.00, 5.24]13% [0%, 25%]26%48%-0.01+0.372026-08-08 → 2026-08-30
tmin12Zbilinear365d23 1 QC3.55 [2.18, 4.81]2.22+3.22 [1.53, 4.68]4.16 [2.91, 5.20]13% [0%, 29%]26%48%-0.01+0.372026-08-08 → 2026-08-30
tmin12Zbilinearall23 1 QC3.55 [2.04, 4.84]2.22+3.22 [1.42, 4.71]4.16 [2.64, 5.21]13% [0%, 29%]26%48%-0.01+0.372026-08-08 → 2026-08-30
tmin12Znearest30d23 1 QC3.42 [2.34, 4.54]2.13+3.19 [2.02, 4.35]4.05 [3.09, 4.94]17% [0%, 33%]30%48%+0.03+0.392026-08-08 → 2026-08-30
tmin12Znearest90d23 1 QC3.42 [2.23, 4.71]2.13+3.19 [1.97, 4.52]4.05 [2.97, 5.08]17% [0%, 33%]30%48%+0.03+0.392026-08-08 → 2026-08-30
tmin12Znearest365d23 1 QC3.42 [2.05, 4.64]2.13+3.19 [1.75, 4.47]4.05 [2.89, 5.04]17% [0%, 36%]30%48%+0.03+0.392026-08-08 → 2026-08-30
tmin12Znearestall23 1 QC3.42 [1.94, 4.75]2.13+3.19 [1.68, 4.47]4.05 [2.51, 5.06]17% [0%, 36%]30%48%+0.03+0.392026-08-08 → 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 7, 00Z bilinear tmax+10+50-5-102026-08-08: +1.19 °F2026-08-09: -3.91 °F2026-08-10: +6.7 °F2026-08-11: +2.96 °F2026-08-12: +0.59 °F2026-08-13: +0.65 °F2026-08-14: +2.28 °F2026-08-15: -0.95 °F2026-08-16: +0.36 °F2026-08-17: -2.88 °F2026-08-18: -0.13 °F2026-08-19: +1.03 °F2026-08-20: -0.3 °F2026-08-21: -1.87 °F2026-08-22: -4.94 °F2026-08-23: -3.22 °F2026-08-24: -3.56 °F2026-08-25: -5.09 °F2026-08-26: -0.56 °F2026-08-27: -2.94 °F2026-08-28: -1.36 °F2026-08-29: -3.37 °F2026-08-30: -1.94 °F2026-08-082026-08-30°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 (23 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-1.94
2026-08-29-3.37
2026-08-28-1.36
2026-08-27-2.94
2026-08-26-0.56
2026-08-25-5.09
2026-08-24-3.56
2026-08-23-3.22
2026-08-22-4.94
2026-08-21-1.87
2026-08-20-0.30
2026-08-19+1.03
2026-08-18-0.13
2026-08-17-2.88
2026-08-16+0.36
2026-08-15-0.95
2026-08-14+2.28
2026-08-13+0.65
2026-08-12+0.59
2026-08-11+2.96
2026-08-10+6.70
2026-08-09-3.91
2026-08-08+1.19

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KIAH, lead day 7-10 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: 1 day-4 to -3 °F: 4 days-3 to -2 °F: 2 days-2 to -1 °F: 3 days-1 to 0 °F: 4 days0 to 1 °F: 3 days1 to 2 °F: 2 days2 to 3 °F: 2 days3 to 4 °F: 0 days4 to 5 °F: 0 days5 to 6 °F: 0 days6 to 7 °F: 1 day7 to 8 °F: 0 days8 to 9 °F: 0 days9 to 10 °F: 0 daysdashed: P50 |e| 1.94 · P90 |e| 4.74 °F-100+10 °Fn = 23 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
-5.00-4.001
-4.00-3.004
-3.00-2.002
-2.00-1.003
-1.00+0.004
+0.00+1.003
+1.00+2.002
+2.00+3.002
+3.00+4.000
+4.00+5.000
+5.00+6.000
+6.00+7.001
+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
2026-08232.29 -0.92

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-08 → 2026-08-30 23
NCEP GFS2026-08-08 → 2026-08-30 23
NCEP GFS2026-08-08 → 2026-08-30 23
NCEP GFS2026-08-08 → 2026-08-30 23

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 23 -0.87 [-2.18, 0.80] no
GraphCast (IFS init) 23 -3.83 [-5.79, -1.06] yes
ECMWF IFS HRES 18 -1.51 [-2.44, -0.27] yes
Persistence (baseline) 23 -1.05 [-2.32, 0.14] no

Cite this page

ShortCastCheck, KIAH gfs lead 7, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KIAH/model/gfs/lead/7/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KIAH (Houston Bush), model gfs, lead day 7. 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/7/

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