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

Houston Bush · ECMWF AIFS Single · lead day 9

KIAH · aifs_single · lead 9

Target day = initialization date + 9 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, aifs-single-gpid5, 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
tmax00Zbilinear30d21 1 QC3.76 [2.02, 5.43]2.06-3.51 [-5.32, -1.44]4.55 [2.27, 6.10]14% [0%, 33%]19%38%-0.13+0.332026-08-10 → 2026-08-30
tmax00Zbilinear90d21 1 QC3.76 [1.78, 5.47]2.06-3.51 [-5.35, -1.09]4.55 [1.85, 6.16]14% [0%, 40%]19%38%-0.13+0.332026-08-10 → 2026-08-30
tmax00Zbilinear365d21 1 QC3.76 [1.84, 5.61]2.06-3.51 [-5.54, -1.08]4.55 [1.90, 6.34]14% [0%, 37%]19%38%-0.13+0.332026-08-10 → 2026-08-30
tmax00Zbilinearall21 1 QC3.76 [1.79, 5.90]2.06-3.51 [-5.83, -1.20]4.55 [1.87, 6.53]14% [0%, 39%]19%38%-0.13+0.332026-08-10 → 2026-08-30
tmax00Znearest30d21 1 QC3.95 [2.16, 5.67]2.01-3.81 [-5.60, -1.79]4.76 [2.44, 6.31]10% [0%, 19%]19%38%-0.19+0.352026-08-10 → 2026-08-30
tmax00Znearest90d21 1 QC3.95 [1.85, 5.66]2.01-3.81 [-5.61, -1.44]4.76 [2.09, 6.37]10% [0%, 20%]19%38%-0.19+0.352026-08-10 → 2026-08-30
tmax00Znearest365d21 1 QC3.95 [1.89, 5.85]2.01-3.81 [-5.78, -1.42]4.76 [2.11, 6.55]10% [0%, 20%]19%38%-0.19+0.352026-08-10 → 2026-08-30
tmax00Znearestall21 1 QC3.95 [1.96, 6.16]2.01-3.81 [-6.11, -1.48]4.76 [2.11, 6.75]10% [0%, 20%]19%38%-0.19+0.352026-08-10 → 2026-08-30
tmax12Zbilinear30d21 1 QC4.26 [2.71, 5.78]2.24-3.88 [-5.70, -1.59]5.01 [3.04, 6.51]10% [0%, 25%]19%33%-0.28+0.272026-08-10 → 2026-08-30
tmax12Zbilinear90d21 1 QC4.26 [2.56, 5.93]2.24-3.88 [-5.80, -1.06]5.01 [2.91, 6.65]10% [0%, 30%]19%33%-0.28+0.272026-08-10 → 2026-08-30
tmax12Zbilinear365d21 1 QC4.26 [2.50, 6.28]2.24-3.88 [-6.28, -1.22]5.01 [2.86, 6.94]10% [0%, 29%]19%33%-0.28+0.272026-08-10 → 2026-08-30
tmax12Zbilinearall21 1 QC4.26 [2.55, 6.35]2.24-3.88 [-6.35, -1.37]5.01 [2.87, 7.03]10% [0%, 29%]19%33%-0.28+0.272026-08-10 → 2026-08-30
tmax12Znearest30d21 1 QC4.51 [2.87, 6.06]2.27-4.18 [-6.01, -1.92]5.27 [3.24, 6.82]10% [0%, 19%]14%33%-0.35+0.262026-08-10 → 2026-08-30
tmax12Znearest90d21 1 QC4.51 [2.65, 6.23]2.27-4.18 [-6.09, -1.40]5.27 [2.97, 6.95]10% [0%, 20%]14%33%-0.35+0.262026-08-10 → 2026-08-30
tmax12Znearest365d21 1 QC4.51 [2.62, 6.61]2.27-4.18 [-6.61, -1.54]5.27 [2.93, 7.27]10% [0%, 20%]14%33%-0.35+0.262026-08-10 → 2026-08-30
tmax12Znearestall21 1 QC4.51 [2.66, 6.65]2.27-4.18 [-6.65, -1.68]5.27 [2.99, 7.35]10% [0%, 20%]14%33%-0.35+0.262026-08-10 → 2026-08-30
tmin00Zbilinear30d21 1 QC2.61 [1.84, 3.43]2.61+0.12 [-1.78, 2.05]3.06 [2.28, 3.82]24% [0%, 46%]29%62%+0.32+0.312026-08-10 → 2026-08-30
tmin00Zbilinear90d21 1 QC2.61 [1.82, 3.51]2.61+0.12 [-1.96, 2.38]3.06 [2.24, 4.00]24% [0%, 47%]29%62%+0.32+0.312026-08-10 → 2026-08-30
tmin00Zbilinear365d21 1 QC2.61 [1.75, 3.48]2.61+0.12 [-2.08, 2.29]3.06 [2.12, 3.93]24% [0%, 48%]29%62%+0.32+0.312026-08-10 → 2026-08-30
tmin00Zbilinearall21 1 QC2.61 [1.80, 3.45]2.61+0.12 [-2.27, 2.32]3.06 [2.08, 3.96]24% [0%, 46%]29%62%+0.32+0.312026-08-10 → 2026-08-30
tmin00Znearest30d21 1 QC2.61 [1.81, 3.51]2.61-0.08 [-1.96, 1.88]3.08 [2.20, 3.86]24% [0%, 46%]29%62%+0.32+0.312026-08-10 → 2026-08-30
tmin00Znearest90d21 1 QC2.61 [1.78, 3.53]2.61-0.08 [-2.14, 2.21]3.08 [2.16, 4.03]24% [0%, 47%]29%62%+0.32+0.312026-08-10 → 2026-08-30
tmin00Znearest365d21 1 QC2.61 [1.70, 3.52]2.61-0.08 [-2.36, 2.11]3.08 [2.07, 3.99]24% [0%, 48%]29%62%+0.32+0.312026-08-10 → 2026-08-30
tmin00Znearestall21 1 QC2.61 [1.73, 3.52]2.61-0.08 [-2.47, 2.13]3.08 [2.05, 3.99]24% [0%, 46%]29%62%+0.32+0.312026-08-10 → 2026-08-30
tmin12Zbilinear30d21 1 QC2.45 [1.88, 3.03]2.43-0.09 [-1.62, 1.51]2.81 [2.22, 3.41]10% [0%, 22%]48%71%+0.37+0.362026-08-10 → 2026-08-30
tmin12Zbilinear90d21 1 QC2.45 [1.88, 3.16]2.43-0.09 [-1.78, 1.88]2.81 [2.23, 3.54]10% [0%, 22%]48%71%+0.37+0.362026-08-10 → 2026-08-30
tmin12Zbilinear365d21 1 QC2.45 [1.82, 3.17]2.43-0.09 [-2.00, 1.81]2.81 [2.15, 3.50]10% [0%, 25%]48%71%+0.37+0.362026-08-10 → 2026-08-30
tmin12Zbilinearall21 1 QC2.45 [1.81, 3.10]2.43-0.09 [-2.13, 1.79]2.81 [2.07, 3.50]10% [0%, 23%]48%71%+0.37+0.362026-08-10 → 2026-08-30
tmin12Znearest30d21 1 QC2.50 [1.86, 3.13]2.44-0.27 [-1.81, 1.33]2.84 [2.17, 3.45]10% [0%, 22%]38%71%+0.35+0.362026-08-10 → 2026-08-30
tmin12Znearest90d21 1 QC2.50 [1.85, 3.27]2.44-0.27 [-1.98, 1.70]2.84 [2.15, 3.58]10% [0%, 22%]38%71%+0.35+0.362026-08-10 → 2026-08-30
tmin12Znearest365d21 1 QC2.50 [1.79, 3.25]2.44-0.27 [-2.21, 1.64]2.84 [2.09, 3.54]10% [0%, 25%]38%71%+0.35+0.362026-08-10 → 2026-08-30
tmin12Znearestall21 1 QC2.50 [1.80, 3.19]2.44-0.27 [-2.34, 1.61]2.84 [2.08, 3.54]10% [0%, 23%]38%71%+0.35+0.362026-08-10 → 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 ECMWF AIFS Single at KIAH, lead day 9, 00Z bilinear tmax+20+100-10-202026-08-10: +1.63 °F2026-08-11: -2.06 °F2026-08-12: -3.35 °F2026-08-13: -2.62 °F2026-08-14: +0.28 °F2026-08-15: -3.52 °F2026-08-16: -4.48 °F2026-08-17: -3.78 °F2026-08-18: -3.14 °F2026-08-19: -3.49 °F2026-08-20: -5.27 °F2026-08-21: -5 °F2026-08-22: -7.35 °F2026-08-23: -5.93 °F2026-08-24: -11.95 °F2026-08-25: -5.93 °F2026-08-26: -3.01 °F2026-08-27: -2.12 °F2026-08-28: +0.72 °F2026-08-29: -1 °F2026-08-30: -2.41 °F2026-08-102026-08-30°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 (21 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-2.41
2026-08-29-1.00
2026-08-28+0.72
2026-08-27-2.12
2026-08-26-3.01
2026-08-25-5.93
2026-08-24-11.95
2026-08-23-5.93
2026-08-22-7.35
2026-08-21-5.00
2026-08-20-5.27
2026-08-19-3.49
2026-08-18-3.14
2026-08-17-3.78
2026-08-16-4.48
2026-08-15-3.52
2026-08-14+0.28
2026-08-13-2.62
2026-08-12-3.35
2026-08-11-2.06
2026-08-10+1.63

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KIAH, lead day 9-20 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: 5 days-4 to -2 °F: 10 days-2 to 0 °F: 1 day0 to 2 °F: 3 days2 to 4 °F: 0 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| 3.35 · P90 |e| 5.93 °F-200+20 °Fn = 21 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
-6.00-4.005
-4.00-2.0010
-2.00+0.001
+0.00+2.003
+2.00+4.000
+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
2026-08213.76 -3.51

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-10 → 2026-08-30 21
ECMWF AIFS Single2026-08-10 → 2026-08-30 21
ECMWF AIFS Single2026-08-10 → 2026-08-30 21
ECMWF AIFS Single2026-08-10 → 2026-08-30 21

Compared with other models

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

Other modelCommon days MAE difference °FDistinguishable
NCEP GFS 21 +0.89 [-1.06, 2.24] no
GraphCast (IFS init) 21 -2.62 [-3.52, -1.51] yes
ECMWF IFS HRES 16 +0.36 [-1.39, 1.22] no
Persistence (baseline) 21 +0.43 [-1.39, 1.93] no

Cite this page

ShortCastCheck, KIAH aifs_single lead 9, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KIAH/model/aifs_single/lead/9/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KIAH (Houston Bush), model aifs_single, lead day 9. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KIAH/model/aifs_single/lead/9/

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

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