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

Houston Bush · ECMWF AIFS Single · lead day 8

KIAH · aifs_single · lead 8

Target day = initialization date + 8 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
tmax00Zbilinear30d22 1 QC3.44 [1.93, 4.96]1.90-3.23 [-4.93, -1.42]4.16 [2.15, 5.61]14% [0%, 29%]27%45%+0.02+0.432026-08-09 → 2026-08-30
tmax00Zbilinear90d22 1 QC3.44 [1.72, 5.06]1.90-3.23 [-4.98, -1.17]4.16 [1.99, 5.70]14% [0%, 30%]27%45%+0.02+0.432026-08-09 → 2026-08-30
tmax00Zbilinear365d22 1 QC3.44 [1.80, 5.36]1.90-3.23 [-5.36, -1.22]4.16 [2.00, 5.91]14% [0%, 31%]27%45%+0.02+0.432026-08-09 → 2026-08-30
tmax00Zbilinearall22 1 QC3.44 [1.74, 5.36]1.90-3.23 [-5.36, -1.28]4.16 [1.94, 6.00]14% [0%, 31%]27%45%+0.02+0.432026-08-09 → 2026-08-30
tmax00Znearest30d22 1 QC3.67 [2.14, 5.22]1.89-3.49 [-5.18, -1.70]4.38 [2.35, 5.85]9% [0%, 18%]27%41%-0.05+0.442026-08-09 → 2026-08-30
tmax00Znearest90d22 1 QC3.67 [1.93, 5.30]1.89-3.49 [-5.23, -1.45]4.38 [2.15, 5.94]9% [0%, 18%]27%41%-0.05+0.442026-08-09 → 2026-08-30
tmax00Znearest365d22 1 QC3.67 [2.01, 5.60]1.89-3.49 [-5.60, -1.50]4.38 [2.18, 6.19]9% [0%, 18%]27%41%-0.05+0.442026-08-09 → 2026-08-30
tmax00Znearestall22 1 QC3.67 [1.94, 5.61]1.89-3.49 [-5.60, -1.50]4.38 [2.12, 6.25]9% [0%, 18%]27%41%-0.05+0.442026-08-09 → 2026-08-30
tmax12Zbilinear30d22 1 QC3.32 [1.92, 4.49]1.45-3.31 [-4.49, -1.90]3.78 [2.08, 4.81]5% [0%, 16%]18%50%+0.05+0.572026-08-09 → 2026-08-30
tmax12Zbilinear90d22 1 QC3.32 [1.77, 4.51]1.45-3.31 [-4.51, -1.75]3.78 [1.91, 4.88]5% [0%, 20%]18%50%+0.05+0.572026-08-09 → 2026-08-30
tmax12Zbilinear365d22 1 QC3.32 [1.81, 4.73]1.45-3.31 [-4.73, -1.77]3.78 [1.94, 5.02]5% [0%, 18%]18%50%+0.05+0.572026-08-09 → 2026-08-30
tmax12Zbilinearall22 1 QC3.32 [1.81, 4.57]1.45-3.31 [-4.57, -1.79]3.78 [1.94, 5.00]5% [0%, 18%]18%50%+0.05+0.572026-08-09 → 2026-08-30
tmax12Znearest30d22 1 QC3.65 [2.30, 4.76]1.37-3.65 [-4.76, -2.30]4.05 [2.46, 5.06]5% [0%, 16%]9%41%-0.04+0.592026-08-09 → 2026-08-30
tmax12Znearest90d22 1 QC3.65 [2.13, 4.76]1.37-3.65 [-4.76, -2.13]4.05 [2.24, 5.12]5% [0%, 20%]9%41%-0.04+0.592026-08-09 → 2026-08-30
tmax12Znearest365d22 1 QC3.65 [2.18, 5.00]1.37-3.65 [-5.00, -2.18]4.05 [2.27, 5.28]5% [0%, 18%]9%41%-0.04+0.592026-08-09 → 2026-08-30
tmax12Znearestall22 1 QC3.65 [2.18, 4.90]1.37-3.65 [-4.90, -2.18]4.05 [2.25, 5.25]5% [0%, 18%]9%41%-0.04+0.592026-08-09 → 2026-08-30
tmin00Zbilinear30d22 1 QC2.45 [1.94, 2.88]2.44+0.23 [-1.46, 1.82]2.83 [2.40, 3.17]23% [7%, 47%]36%73%+0.28+0.282026-08-09 → 2026-08-30
tmin00Zbilinear90d22 1 QC2.45 [1.94, 2.91]2.44+0.23 [-1.50, 2.00]2.83 [2.35, 3.19]23% [5%, 50%]36%73%+0.28+0.282026-08-09 → 2026-08-30
tmin00Zbilinear365d22 1 QC2.45 [1.87, 2.97]2.44+0.23 [-1.76, 1.99]2.83 [2.28, 3.24]23% [0%, 56%]36%73%+0.28+0.282026-08-09 → 2026-08-30
tmin00Zbilinearall22 1 QC2.45 [1.79, 2.91]2.44+0.23 [-1.89, 2.00]2.83 [2.23, 3.19]23% [0%, 60%]36%73%+0.28+0.282026-08-09 → 2026-08-30
tmin00Znearest30d22 1 QC2.45 [1.88, 2.94]2.45+0.03 [-1.67, 1.64]2.83 [2.29, 3.24]18% [5%, 43%]41%59%+0.28+0.282026-08-09 → 2026-08-30
tmin00Znearest90d22 1 QC2.45 [1.86, 2.99]2.45+0.03 [-1.73, 1.80]2.83 [2.25, 3.26]18% [4%, 50%]41%59%+0.28+0.282026-08-09 → 2026-08-30
tmin00Znearest365d22 1 QC2.45 [1.78, 3.09]2.45+0.03 [-1.96, 1.81]2.83 [2.17, 3.30]18% [0%, 50%]41%59%+0.28+0.282026-08-09 → 2026-08-30
tmin00Znearestall22 1 QC2.45 [1.74, 3.07]2.45+0.03 [-2.11, 1.79]2.83 [2.13, 3.28]18% [0%, 60%]41%59%+0.28+0.282026-08-09 → 2026-08-30
tmin12Zbilinear30d22 1 QC2.06 [1.69, 2.32]2.06+0.01 [-1.45, 1.60]2.32 [2.01, 2.56]23% [11%, 40%]36%82%+0.40+0.392026-08-09 → 2026-08-30
tmin12Zbilinear90d22 1 QC2.06 [1.67, 2.39]2.06+0.01 [-1.59, 1.78]2.32 [1.99, 2.59]23% [9%, 43%]36%82%+0.40+0.392026-08-09 → 2026-08-30
tmin12Zbilinear365d22 1 QC2.06 [1.61, 2.34]2.06+0.01 [-1.74, 1.78]2.32 [1.93, 2.59]23% [9%, 45%]36%82%+0.40+0.392026-08-09 → 2026-08-30
tmin12Zbilinearall22 1 QC2.06 [1.61, 2.38]2.06+0.01 [-1.80, 1.80]2.32 [1.93, 2.60]23% [9%, 44%]36%82%+0.40+0.392026-08-09 → 2026-08-30
tmin12Znearest30d22 1 QC2.05 [1.68, 2.36]2.04-0.17 [-1.64, 1.42]2.30 [1.98, 2.54]23% [11%, 40%]45%82%+0.40+0.402026-08-09 → 2026-08-30
tmin12Znearest90d22 1 QC2.05 [1.60, 2.41]2.04-0.17 [-1.76, 1.59]2.30 [1.93, 2.59]23% [9%, 43%]45%82%+0.40+0.402026-08-09 → 2026-08-30
tmin12Znearest365d22 1 QC2.05 [1.54, 2.38]2.04-0.17 [-1.92, 1.60]2.30 [1.86, 2.56]23% [9%, 45%]45%82%+0.40+0.402026-08-09 → 2026-08-30
tmin12Znearestall22 1 QC2.05 [1.52, 2.42]2.04-0.17 [-1.99, 1.63]2.30 [1.81, 2.59]23% [9%, 44%]45%82%+0.40+0.402026-08-09 → 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 8, 00Z bilinear tmax+20+100-10-202026-08-09: -2.34 °F2026-08-10: +2.18 °F2026-08-11: -1.35 °F2026-08-12: -3.23 °F2026-08-13: -2.52 °F2026-08-14: +0.15 °F2026-08-15: -3.71 °F2026-08-16: -4.45 °F2026-08-17: -3.67 °F2026-08-18: -2.98 °F2026-08-19: -3.25 °F2026-08-20: -4.47 °F2026-08-21: -5.78 °F2026-08-22: -7.16 °F2026-08-23: -10.35 °F2026-08-24: -6.58 °F2026-08-25: -3.1 °F2026-08-26: -3.77 °F2026-08-27: -0.78 °F2026-08-28: -0.36 °F2026-08-29: -1.63 °F2026-08-30: -1.86 °F2026-08-092026-08-30°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 (22 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-1.86
2026-08-29-1.63
2026-08-28-0.36
2026-08-27-0.78
2026-08-26-3.77
2026-08-25-3.10
2026-08-24-6.58
2026-08-23-10.35
2026-08-22-7.16
2026-08-21-5.78
2026-08-20-4.47
2026-08-19-3.25
2026-08-18-2.98
2026-08-17-3.67
2026-08-16-4.45
2026-08-15-3.71
2026-08-14+0.15
2026-08-13-2.52
2026-08-12-3.23
2026-08-11-1.35
2026-08-10+2.18
2026-08-09-2.34

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KIAH, lead day 8-20 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: 2 days-6 to -4 °F: 3 days-4 to -2 °F: 9 days-2 to 0 °F: 5 days0 to 2 °F: 1 day2 to 4 °F: 1 day4 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| 3.17 · P90 |e| 6.5 °F-200+20 °Fn = 22 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
-8.00-6.002
-6.00-4.003
-4.00-2.009
-2.00+0.005
+0.00+2.001
+2.00+4.001
+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
2026-08223.44 -3.23

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22

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 22 +1.00 [-0.40, 1.91] no
GraphCast (IFS init) 22 -2.53 [-3.48, -0.89] yes
ECMWF IFS HRES 17 -0.25 [-2.23, 1.70] no
Persistence (baseline) 22 -0.06 [-2.43, 1.49] no

Cite this page

ShortCastCheck, KIAH aifs_single lead 8, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KIAH/model/aifs_single/lead/8/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KIAH (Houston Bush), model aifs_single, lead day 8. 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/8/

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