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

San Antonio Intl · ECMWF AIFS Single · lead day 9

KSAT · 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 QC3.14 [1.84, 4.44]2.11-2.87 [-4.36, -1.24]3.86 [2.29, 4.97]14% [0%, 38%]38%67%-0.47-0.232026-08-10 → 2026-08-30
tmax00Zbilinear90d21 1 QC3.14 [1.65, 4.49]2.11-2.87 [-4.44, -0.77]3.86 [1.84, 5.03]14% [0%, 44%]38%67%-0.47-0.232026-08-10 → 2026-08-30
tmax00Zbilinear365d21 1 QC3.14 [1.61, 4.63]2.11-2.87 [-4.59, -0.88]3.86 [1.76, 5.10]14% [0%, 45%]38%67%-0.47-0.232026-08-10 → 2026-08-30
tmax00Zbilinearall21 1 QC3.14 [1.50, 4.77]2.11-2.87 [-4.71, -0.80]3.86 [1.68, 5.21]14% [0%, 50%]38%67%-0.47-0.232026-08-10 → 2026-08-30
tmax00Znearest30d21 1 QC2.85 [1.67, 4.07]2.11-2.46 [-3.95, -0.81]3.57 [2.13, 4.64]19% [5%, 38%]48%67%-0.33-0.232026-08-10 → 2026-08-30
tmax00Znearest90d21 1 QC2.85 [1.54, 4.12]2.11-2.46 [-4.04, -0.37]3.57 [1.75, 4.69]19% [5%, 43%]48%67%-0.33-0.232026-08-10 → 2026-08-30
tmax00Znearest365d21 1 QC2.85 [1.42, 4.27]2.11-2.46 [-4.19, -0.47]3.57 [1.63, 4.75]19% [0%, 42%]48%67%-0.33-0.232026-08-10 → 2026-08-30
tmax00Znearestall21 1 QC2.85 [1.32, 4.35]2.11-2.46 [-4.31, -0.40]3.57 [1.46, 4.86]19% [0%, 46%]48%67%-0.33-0.232026-08-10 → 2026-08-30
tmax12Zbilinear30d21 1 QC3.39 [1.91, 4.49]1.71-3.31 [-4.49, -1.77]3.97 [2.14, 4.95]10% [0%, 26%]33%48%-0.58+0.002026-08-10 → 2026-08-30
tmax12Zbilinear90d21 1 QC3.39 [1.73, 4.60]1.71-3.31 [-4.60, -1.53]3.97 [1.85, 5.07]10% [0%, 29%]33%48%-0.58+0.002026-08-10 → 2026-08-30
tmax12Zbilinear365d21 1 QC3.39 [1.72, 4.68]1.71-3.31 [-4.66, -1.53]3.97 [1.84, 5.13]10% [0%, 29%]33%48%-0.58+0.002026-08-10 → 2026-08-30
tmax12Zbilinearall21 1 QC3.39 [1.74, 4.68]1.71-3.31 [-4.68, -1.58]3.97 [1.83, 5.18]10% [0%, 29%]33%48%-0.58+0.002026-08-10 → 2026-08-30
tmax12Znearest30d21 1 QC3.04 [1.64, 4.10]1.73-2.91 [-4.09, -1.36]3.66 [1.86, 4.62]10% [0%, 17%]38%62%-0.42-0.012026-08-10 → 2026-08-30
tmax12Znearest90d21 1 QC3.04 [1.41, 4.21]1.73-2.91 [-4.20, -1.13]3.66 [1.51, 4.72]10% [0%, 17%]38%62%-0.42-0.012026-08-10 → 2026-08-30
tmax12Znearest365d21 1 QC3.04 [1.44, 4.29]1.73-2.91 [-4.27, -1.13]3.66 [1.56, 4.78]10% [0%, 17%]38%62%-0.42-0.012026-08-10 → 2026-08-30
tmax12Znearestall21 1 QC3.04 [1.41, 4.29]1.73-2.91 [-4.29, -1.15]3.66 [1.45, 4.85]10% [0%, 17%]38%62%-0.42-0.012026-08-10 → 2026-08-30
tmin00Zbilinear30d21 1 QC1.70 [0.97, 2.95]1.65-0.26 [-1.45, 0.96]2.34 [1.30, 3.58]33% [9%, 54%]71%81%+0.06+0.072026-08-10 → 2026-08-30
tmin00Zbilinear90d21 1 QC1.70 [0.95, 3.44]1.65-0.26 [-1.54, 1.16]2.34 [1.28, 3.88]33% [0%, 57%]71%81%+0.06+0.072026-08-10 → 2026-08-30
tmin00Zbilinear365d21 1 QC1.70 [0.88, 3.37]1.65-0.26 [-1.51, 1.15]2.34 [1.22, 3.81]33% [0%, 57%]71%81%+0.06+0.072026-08-10 → 2026-08-30
tmin00Zbilinearall21 1 QC1.70 [0.86, 3.45]1.65-0.26 [-1.54, 1.06]2.34 [1.07, 3.80]33% [0%, 57%]71%81%+0.06+0.072026-08-10 → 2026-08-30
tmin00Znearest30d21 1 QC1.66 [0.99, 2.92]1.66-0.04 [-1.24, 1.20]2.33 [1.23, 3.64]38% [11%, 60%]76%86%+0.08+0.062026-08-10 → 2026-08-30
tmin00Znearest90d21 1 QC1.66 [0.98, 3.41]1.66-0.04 [-1.32, 1.40]2.33 [1.23, 3.94]38% [0%, 60%]76%86%+0.08+0.062026-08-10 → 2026-08-30
tmin00Znearest365d21 1 QC1.66 [0.94, 3.33]1.66-0.04 [-1.30, 1.39]2.33 [1.19, 3.84]38% [0%, 62%]76%86%+0.08+0.062026-08-10 → 2026-08-30
tmin00Znearestall21 1 QC1.66 [0.93, 3.44]1.66-0.04 [-1.33, 1.30]2.33 [1.12, 3.84]38% [0%, 60%]76%86%+0.08+0.062026-08-10 → 2026-08-30
tmin12Zbilinear30d21 1 QC1.60 [1.13, 2.33]1.43-0.70 [-1.76, 0.20]2.05 [1.47, 2.88]33% [14%, 48%]71%86%+0.12+0.192026-08-10 → 2026-08-30
tmin12Zbilinear90d21 1 QC1.60 [1.10, 2.43]1.43-0.70 [-1.93, 0.34]2.05 [1.44, 3.02]33% [8%, 50%]71%86%+0.12+0.192026-08-10 → 2026-08-30
tmin12Zbilinear365d21 1 QC1.60 [1.07, 2.43]1.43-0.70 [-1.90, 0.35]2.05 [1.38, 3.06]33% [7%, 50%]71%86%+0.12+0.192026-08-10 → 2026-08-30
tmin12Zbilinearall21 1 QC1.60 [0.94, 2.49]1.43-0.70 [-1.90, 0.27]2.05 [1.21, 3.11]33% [8%, 50%]71%86%+0.12+0.192026-08-10 → 2026-08-30
tmin12Znearest30d21 1 QC1.54 [1.11, 2.29]1.43-0.48 [-1.55, 0.44]2.00 [1.39, 2.83]33% [17%, 46%]76%90%+0.15+0.192026-08-10 → 2026-08-30
tmin12Znearest90d21 1 QC1.54 [1.09, 2.40]1.43-0.48 [-1.72, 0.59]2.00 [1.36, 3.03]33% [10%, 46%]76%90%+0.15+0.192026-08-10 → 2026-08-30
tmin12Znearest365d21 1 QC1.54 [1.05, 2.40]1.43-0.48 [-1.69, 0.59]2.00 [1.30, 3.02]33% [12%, 47%]76%90%+0.15+0.192026-08-10 → 2026-08-30
tmin12Znearestall21 1 QC1.54 [0.95, 2.48]1.43-0.48 [-1.68, 0.52]2.00 [1.18, 3.07]33% [0%, 49%]76%90%+0.15+0.192026-08-10 → 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 KSAT, lead day 9, 00Z bilinear tmax+10+50-5-102026-08-10: -1.3 °F2026-08-11: -6.22 °F2026-08-12: -1.53 °F2026-08-13: -2.3 °F2026-08-14: +0.31 °F2026-08-15: -2.68 °F2026-08-16: -2.02 °F2026-08-17: -1.11 °F2026-08-18: -1.52 °F2026-08-19: -6.61 °F2026-08-20: -4.32 °F2026-08-21: -2.55 °F2026-08-22: -5.57 °F2026-08-23: -6.21 °F2026-08-24: -8.21 °F2026-08-25: -5.13 °F2026-08-26: -2.24 °F2026-08-27: -2.74 °F2026-08-28: +1.72 °F2026-08-29: +0.86 °F2026-08-30: -0.85 °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
2026-08-30-0.85
2026-08-29+0.86
2026-08-28+1.72
2026-08-27-2.74
2026-08-26-2.24
2026-08-25-5.13
2026-08-24-8.21
2026-08-23-6.21
2026-08-22-5.57
2026-08-21-2.55
2026-08-20-4.32
2026-08-19-6.61
2026-08-18-1.52
2026-08-17-1.11
2026-08-16-2.02
2026-08-15-2.68
2026-08-14+0.31
2026-08-13-2.30
2026-08-12-1.53
2026-08-11-6.22
2026-08-10-1.30

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KSAT, lead day 9-10 to -9 °F: 0 days-9 to -8 °F: 1 day-8 to -7 °F: 0 days-7 to -6 °F: 3 days-6 to -5 °F: 2 days-5 to -4 °F: 1 day-4 to -3 °F: 0 days-3 to -2 °F: 6 days-2 to -1 °F: 4 days-1 to 0 °F: 1 day0 to 1 °F: 2 days1 to 2 °F: 1 day2 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| 2.3 · P90 |e| 6.22 °F-100+10 °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
-10.00-9.000
-9.00-8.001
-8.00-7.000
-7.00-6.003
-6.00-5.002
-5.00-4.001
-4.00-3.000
-3.00-2.006
-2.00-1.004
-1.00+0.001
+0.00+1.002
+1.00+2.001
+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
2026-08213.14 -2.87

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 +0.73 [-1.12, 1.78] no
GraphCast (IFS init) 21 -3.02 [-3.48, -2.35] yes
ECMWF IFS HRES 16 +0.30 [-1.10, 1.24] no
Persistence (baseline) 21 +1.00 [-0.89, 2.42] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSAT (San Antonio Intl), 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/KSAT/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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