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

Houston Bush · ECMWF AIFS Single · lead day 4

KIAH · aifs_single · lead 4

Target day = initialization date + 4 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
tmax00Zbilinear30d26 1 QC3.60 [2.95, 4.25]1.03-3.60 [-4.25, -2.95]3.84 [3.12, 4.43]4% [0%, 11%]12%31%-0.28+0.632026-08-05 → 2026-08-30
tmax00Zbilinear90d26 1 QC3.60 [2.85, 4.30]1.03-3.60 [-4.30, -2.85]3.84 [2.98, 4.48]4% [0%, 11%]12%31%-0.28+0.632026-08-05 → 2026-08-30
tmax00Zbilinear365d26 1 QC3.60 [2.80, 4.38]1.03-3.60 [-4.38, -2.80]3.84 [2.94, 4.52]4% [0%, 12%]12%31%-0.28+0.632026-08-05 → 2026-08-30
tmax00Zbilinearall26 1 QC3.60 [2.84, 4.38]1.03-3.60 [-4.38, -2.84]3.84 [2.95, 4.51]4% [0%, 11%]12%31%-0.28+0.632026-08-05 → 2026-08-30
tmax00Znearest30d26 1 QC3.93 [3.29, 4.58]1.02-3.93 [-4.58, -3.29]4.16 [3.44, 4.74]0% [0%, 0%]8%23%-0.40+0.642026-08-05 → 2026-08-30
tmax00Znearest90d26 1 QC3.93 [3.20, 4.61]1.02-3.93 [-4.61, -3.20]4.16 [3.34, 4.79]0% [0%, 0%]8%23%-0.40+0.642026-08-05 → 2026-08-30
tmax00Znearest365d26 1 QC3.93 [3.13, 4.70]1.02-3.93 [-4.70, -3.13]4.16 [3.27, 4.83]0% [0%, 0%]8%23%-0.40+0.642026-08-05 → 2026-08-30
tmax00Znearestall26 1 QC3.93 [3.17, 4.69]1.02-3.93 [-4.69, -3.17]4.16 [3.32, 4.84]0% [0%, 0%]8%23%-0.40+0.642026-08-05 → 2026-08-30
tmax12Zbilinear30d26 1 QC3.81 [3.01, 4.57]1.19-3.81 [-4.57, -3.01]4.06 [3.18, 4.76]0% [0%, 0%]8%35%-0.36+0.582026-08-05 → 2026-08-30
tmax12Zbilinear90d26 1 QC3.81 [2.89, 4.66]1.19-3.81 [-4.66, -2.89]4.06 [2.99, 4.82]0% [0%, 0%]8%35%-0.36+0.582026-08-05 → 2026-08-30
tmax12Zbilinear365d26 1 QC3.81 [2.86, 4.75]1.19-3.81 [-4.75, -2.86]4.06 [2.99, 4.89]0% [0%, 0%]8%35%-0.36+0.582026-08-05 → 2026-08-30
tmax12Zbilinearall26 1 QC3.81 [2.86, 4.69]1.19-3.81 [-4.69, -2.86]4.06 [2.97, 4.87]0% [0%, 0%]8%35%-0.36+0.582026-08-05 → 2026-08-30
tmax12Znearest30d26 1 QC4.13 [3.35, 4.89]1.20-4.13 [-4.89, -3.35]4.36 [3.53, 5.06]0% [0%, 0%]4%27%-0.47+0.572026-08-05 → 2026-08-30
tmax12Znearest90d26 1 QC4.13 [3.25, 4.96]1.20-4.13 [-4.96, -3.25]4.36 [3.36, 5.11]0% [0%, 0%]4%27%-0.47+0.572026-08-05 → 2026-08-30
tmax12Znearest365d26 1 QC4.13 [3.22, 5.05]1.20-4.13 [-5.05, -3.22]4.36 [3.34, 5.19]0% [0%, 0%]4%27%-0.47+0.572026-08-05 → 2026-08-30
tmax12Znearestall26 1 QC4.13 [3.20, 5.00]1.20-4.13 [-5.00, -3.20]4.36 [3.32, 5.17]0% [0%, 0%]4%27%-0.47+0.572026-08-05 → 2026-08-30
tmin00Zbilinear30d26 1 QC1.67 [1.03, 2.11]1.68-0.06 [-1.35, 1.09]2.07 [1.51, 2.39]35% [15%, 62%]62%85%+0.41+0.412026-08-05 → 2026-08-30
tmin00Zbilinear90d26 1 QC1.67 [0.95, 2.13]1.68-0.06 [-1.42, 1.27]2.07 [1.39, 2.40]35% [12%, 70%]62%85%+0.41+0.412026-08-05 → 2026-08-30
tmin00Zbilinear365d26 1 QC1.67 [0.89, 2.17]1.68-0.06 [-1.54, 1.29]2.07 [1.34, 2.42]35% [8%, 67%]62%85%+0.41+0.412026-08-05 → 2026-08-30
tmin00Zbilinearall26 1 QC1.67 [0.87, 2.16]1.68-0.06 [-1.66, 1.21]2.07 [1.20, 2.42]35% [11%, 68%]62%85%+0.41+0.412026-08-05 → 2026-08-30
tmin00Znearest30d26 1 QC1.71 [0.98, 2.22]1.70-0.24 [-1.55, 0.92]2.11 [1.50, 2.48]38% [22%, 67%]54%77%+0.40+0.402026-08-05 → 2026-08-30
tmin00Znearest90d26 1 QC1.71 [0.88, 2.25]1.70-0.24 [-1.64, 1.11]2.11 [1.38, 2.50]38% [21%, 73%]54%77%+0.40+0.402026-08-05 → 2026-08-30
tmin00Znearest365d26 1 QC1.71 [0.85, 2.29]1.70-0.24 [-1.77, 1.14]2.11 [1.33, 2.54]38% [20%, 75%]54%77%+0.40+0.402026-08-05 → 2026-08-30
tmin00Znearestall26 1 QC1.71 [0.82, 2.30]1.70-0.24 [-1.88, 1.06]2.11 [1.12, 2.54]38% [21%, 78%]54%77%+0.40+0.402026-08-05 → 2026-08-30
tmin12Zbilinear30d26 1 QC1.67 [0.99, 2.18]1.66-0.22 [-1.52, 0.94]2.09 [1.53, 2.45]38% [15%, 68%]58%85%+0.41+0.422026-08-05 → 2026-08-30
tmin12Zbilinear90d26 1 QC1.67 [0.88, 2.19]1.66-0.22 [-1.57, 1.14]2.09 [1.42, 2.48]38% [15%, 74%]58%85%+0.41+0.422026-08-05 → 2026-08-30
tmin12Zbilinear365d26 1 QC1.67 [0.82, 2.22]1.66-0.22 [-1.68, 1.14]2.09 [1.32, 2.50]38% [13%, 77%]58%85%+0.41+0.422026-08-05 → 2026-08-30
tmin12Zbilinearall26 1 QC1.67 [0.77, 2.21]1.66-0.22 [-1.79, 1.10]2.09 [1.14, 2.49]38% [14%, 78%]58%85%+0.41+0.422026-08-05 → 2026-08-30
tmin12Znearest30d26 1 QC1.72 [0.97, 2.28]1.69-0.41 [-1.74, 0.78]2.15 [1.53, 2.57]38% [15%, 68%]58%81%+0.40+0.412026-08-05 → 2026-08-30
tmin12Znearest90d26 1 QC1.72 [0.87, 2.32]1.69-0.41 [-1.78, 0.99]2.15 [1.39, 2.61]38% [15%, 74%]58%81%+0.40+0.412026-08-05 → 2026-08-30
tmin12Znearest365d26 1 QC1.72 [0.80, 2.35]1.69-0.41 [-1.91, 1.00]2.15 [1.31, 2.63]38% [13%, 77%]58%81%+0.40+0.412026-08-05 → 2026-08-30
tmin12Znearestall26 1 QC1.72 [0.74, 2.38]1.69-0.41 [-2.02, 0.92]2.15 [1.11, 2.63]38% [14%, 78%]58%81%+0.40+0.412026-08-05 → 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 4, 00Z bilinear tmax+10+50-5-102026-08-05: -3.56 °F2026-08-06: -3.22 °F2026-08-07: -3.81 °F2026-08-08: -2.82 °F2026-08-09: -2.38 °F2026-08-10: -1.43 °F2026-08-11: -2.66 °F2026-08-12: -3.6 °F2026-08-13: -2.86 °F2026-08-14: -0.9 °F2026-08-15: -4.2 °F2026-08-16: -4.83 °F2026-08-17: -4.28 °F2026-08-18: -4.22 °F2026-08-19: -3.14 °F2026-08-20: -5.06 °F2026-08-21: -4.76 °F2026-08-22: -5.38 °F2026-08-23: -3.55 °F2026-08-24: -5.49 °F2026-08-25: -3.35 °F2026-08-26: -3.42 °F2026-08-27: -7.34 °F2026-08-28: -2.1 °F2026-08-29: -1.95 °F2026-08-30: -3.18 °F2026-08-052026-08-30°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 (26 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-3.18
2026-08-29-1.95
2026-08-28-2.10
2026-08-27-7.34
2026-08-26-3.42
2026-08-25-3.35
2026-08-24-5.49
2026-08-23-3.55
2026-08-22-5.38
2026-08-21-4.76
2026-08-20-5.06
2026-08-19-3.14
2026-08-18-4.22
2026-08-17-4.28
2026-08-16-4.83
2026-08-15-4.20
2026-08-14-0.90
2026-08-13-2.86
2026-08-12-3.60
2026-08-11-2.66
2026-08-10-1.43
2026-08-09-2.38
2026-08-08-2.82
2026-08-07-3.81
2026-08-06-3.22
2026-08-05-3.56

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KIAH, lead day 4-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 1 day-7 to -6 °F: 0 days-6 to -5 °F: 3 days-5 to -4 °F: 5 days-4 to -3 °F: 9 days-3 to -2 °F: 5 days-2 to -1 °F: 2 days-1 to 0 °F: 1 day0 to 1 °F: 0 days1 to 2 °F: 0 days2 to 3 °F: 0 days3 to 4 °F: 0 days4 to 5 °F: 0 days5 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| 3.48 · P90 |e| 5.22 °F-100+10 °Fn = 26 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
-8.00-7.001
-7.00-6.000
-6.00-5.003
-5.00-4.005
-4.00-3.009
-3.00-2.005
-2.00-1.002
-1.00+0.001
+0.00+1.000
+1.00+2.000
+2.00+3.000
+3.00+4.000
+4.00+5.000
+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
2026-08263.60 -3.60

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-05 → 2026-08-30 26
ECMWF AIFS Single2026-08-05 → 2026-08-30 26
ECMWF AIFS Single2026-08-05 → 2026-08-30 26
ECMWF AIFS Single2026-08-05 → 2026-08-30 26

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 26 +1.45 [0.31, 2.51] yes
GraphCast (IFS init) 25 -2.80 [-3.50, -2.07] yes
ECMWF IFS HRES 20 -0.09 [-1.31, 0.77] no
Persistence (baseline) 26 +0.79 [-0.69, 2.09] no

Cite this page

ShortCastCheck, KIAH aifs_single lead 4, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KIAH/model/aifs_single/lead/4/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KIAH (Houston Bush), model aifs_single, lead day 4. 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/4/

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