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

San Antonio Intl · ECMWF AIFS Single · lead day 1

KSAT · aifs_single · lead 1

Target day = initialization date + 1 day. 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
tmax00Zbilinear30d29 1 QC3.12 [2.67, 3.61]1.24-3.12 [-3.61, -2.67]3.51 [2.88, 4.12]3% [0%, 11%]28%52%-2.01-0.172026-08-02 → 2026-08-30
tmax00Zbilinear90d29 1 QC3.12 [2.67, 3.59]1.24-3.12 [-3.59, -2.67]3.51 [2.88, 4.11]3% [0%, 13%]28%52%-2.01-0.172026-08-02 → 2026-08-30
tmax00Zbilinear365d29 1 QC3.12 [2.65, 3.61]1.24-3.12 [-3.61, -2.65]3.51 [2.84, 4.12]3% [0%, 17%]28%52%-2.01-0.172026-08-02 → 2026-08-30
tmax00Zbilinearall29 1 QC3.12 [2.61, 3.59]1.24-3.12 [-3.59, -2.61]3.51 [2.84, 4.10]3% [0%, 17%]28%52%-2.01-0.172026-08-02 → 2026-08-30
tmax00Znearest30d29 1 QC2.69 [2.24, 3.20]1.27-2.69 [-3.20, -2.24]3.17 [2.47, 3.80]14% [3%, 28%]38%72%-1.60-0.202026-08-02 → 2026-08-30
tmax00Znearest90d29 1 QC2.69 [2.24, 3.17]1.27-2.69 [-3.17, -2.24]3.17 [2.49, 3.79]14% [0%, 29%]38%72%-1.60-0.202026-08-02 → 2026-08-30
tmax00Znearest365d29 1 QC2.69 [2.23, 3.19]1.27-2.69 [-3.19, -2.23]3.17 [2.44, 3.81]14% [0%, 29%]38%72%-1.60-0.202026-08-02 → 2026-08-30
tmax00Znearestall29 1 QC2.69 [2.18, 3.16]1.27-2.69 [-3.16, -2.18]3.17 [2.44, 3.78]14% [0%, 29%]38%72%-1.60-0.202026-08-02 → 2026-08-30
tmax12Zbilinear30d29 1 QC3.67 [3.19, 4.20]1.19-3.67 [-4.20, -3.19]4.00 [3.34, 4.63]0% [0%, 0%]10%38%-2.55-0.122026-08-02 → 2026-08-30
tmax12Zbilinear90d29 1 QC3.67 [3.20, 4.22]1.19-3.67 [-4.22, -3.20]4.00 [3.35, 4.66]0% [0%, 0%]10%38%-2.55-0.122026-08-02 → 2026-08-30
tmax12Zbilinear365d29 1 QC3.67 [3.16, 4.18]1.19-3.67 [-4.18, -3.16]4.00 [3.27, 4.63]0% [0%, 0%]10%38%-2.55-0.122026-08-02 → 2026-08-30
tmax12Zbilinearall29 1 QC3.67 [3.17, 4.21]1.19-3.67 [-4.21, -3.17]4.00 [3.25, 4.63]0% [0%, 0%]10%38%-2.55-0.122026-08-02 → 2026-08-30
tmax12Znearest30d29 1 QC3.25 [2.76, 3.79]1.21-3.25 [-3.79, -2.76]3.64 [2.94, 4.29]3% [0%, 11%]21%52%-2.14-0.152026-08-02 → 2026-08-30
tmax12Znearest90d29 1 QC3.25 [2.76, 3.81]1.21-3.25 [-3.81, -2.76]3.64 [2.95, 4.33]3% [0%, 13%]21%52%-2.14-0.152026-08-02 → 2026-08-30
tmax12Znearest365d29 1 QC3.25 [2.71, 3.77]1.21-3.25 [-3.77, -2.71]3.64 [2.87, 4.29]3% [0%, 17%]21%52%-2.14-0.152026-08-02 → 2026-08-30
tmax12Znearestall29 1 QC3.25 [2.71, 3.80]1.21-3.25 [-3.80, -2.71]3.64 [2.83, 4.29]3% [0%, 17%]21%52%-2.14-0.152026-08-02 → 2026-08-30
tmin00Zbilinear30d29 1 QC1.51 [1.25, 1.74]1.27-0.77 [-1.56, 0.24]1.82 [1.49, 2.11]38% [21%, 55%]79%86%-0.02+0.152026-08-02 → 2026-08-30
tmin00Zbilinear90d29 1 QC1.51 [1.27, 1.77]1.27-0.77 [-1.60, 0.24]1.82 [1.50, 2.17]38% [17%, 56%]79%86%-0.02+0.152026-08-02 → 2026-08-30
tmin00Zbilinear365d29 1 QC1.51 [1.26, 1.80]1.27-0.77 [-1.62, 0.25]1.82 [1.48, 2.19]38% [17%, 59%]79%86%-0.02+0.152026-08-02 → 2026-08-30
tmin00Zbilinearall29 1 QC1.51 [1.19, 1.80]1.27-0.77 [-1.65, 0.34]1.82 [1.43, 2.18]38% [16%, 59%]79%86%-0.02+0.152026-08-02 → 2026-08-30
tmin00Znearest30d29 1 QC1.42 [1.23, 1.65]1.27-0.53 [-1.33, 0.48]1.73 [1.43, 2.03]41% [28%, 53%]76%93%+0.04+0.152026-08-02 → 2026-08-30
tmin00Znearest90d29 1 QC1.42 [1.23, 1.71]1.27-0.53 [-1.37, 0.48]1.73 [1.36, 2.11]41% [25%, 53%]76%93%+0.04+0.152026-08-02 → 2026-08-30
tmin00Znearest365d29 1 QC1.42 [1.23, 1.75]1.27-0.53 [-1.39, 0.50]1.73 [1.37, 2.13]41% [25%, 55%]76%93%+0.04+0.152026-08-02 → 2026-08-30
tmin00Znearestall29 1 QC1.42 [1.21, 1.71]1.27-0.53 [-1.41, 0.59]1.73 [1.36, 2.11]41% [23%, 54%]76%93%+0.04+0.152026-08-02 → 2026-08-30
tmin12Zbilinear30d29 1 QC1.64 [1.29, 1.98]1.17-1.22 [-1.82, -0.48]1.94 [1.56, 2.31]34% [17%, 53%]66%90%-0.11+0.222026-08-02 → 2026-08-30
tmin12Zbilinear90d29 1 QC1.64 [1.33, 2.02]1.17-1.22 [-1.89, -0.46]1.94 [1.58, 2.35]34% [14%, 53%]66%90%-0.11+0.222026-08-02 → 2026-08-30
tmin12Zbilinear365d29 1 QC1.64 [1.32, 2.02]1.17-1.22 [-1.91, -0.46]1.94 [1.59, 2.39]34% [14%, 55%]66%90%-0.11+0.222026-08-02 → 2026-08-30
tmin12Zbilinearall29 1 QC1.64 [1.25, 2.01]1.17-1.22 [-1.95, -0.40]1.94 [1.52, 2.35]34% [12%, 57%]66%90%-0.11+0.222026-08-02 → 2026-08-30
tmin12Znearest30d29 1 QC1.52 [1.23, 1.82]1.16-0.99 [-1.60, -0.25]1.81 [1.45, 2.16]34% [18%, 48%]72%90%-0.02+0.222026-08-02 → 2026-08-30
tmin12Znearest90d29 1 QC1.52 [1.27, 1.85]1.16-0.99 [-1.67, -0.22]1.81 [1.47, 2.21]34% [14%, 47%]72%90%-0.02+0.222026-08-02 → 2026-08-30
tmin12Znearest365d29 1 QC1.52 [1.27, 1.88]1.16-0.99 [-1.67, -0.21]1.81 [1.46, 2.24]34% [14%, 48%]72%90%-0.02+0.222026-08-02 → 2026-08-30
tmin12Znearestall29 1 QC1.52 [1.21, 1.88]1.16-0.99 [-1.72, -0.16]1.81 [1.42, 2.22]34% [12%, 50%]72%90%-0.02+0.222026-08-02 → 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 1, 00Z bilinear tmax+10+50-5-102026-08-02: -5.83 °F2026-08-03: -3.51 °F2026-08-04: -1.96 °F2026-08-05: -1.45 °F2026-08-06: -3.12 °F2026-08-07: -3.09 °F2026-08-08: -1.16 °F2026-08-09: -5.17 °F2026-08-10: -6.5 °F2026-08-11: -1.18 °F2026-08-12: -2.82 °F2026-08-13: -4.23 °F2026-08-14: -3.99 °F2026-08-15: -3.03 °F2026-08-16: -1.88 °F2026-08-17: -3.11 °F2026-08-18: -2.58 °F2026-08-19: -1.62 °F2026-08-20: -2.51 °F2026-08-21: -2.11 °F2026-08-22: -3.29 °F2026-08-23: -3.38 °F2026-08-24: -2.72 °F2026-08-25: -2.35 °F2026-08-26: -1.48 °F2026-08-27: -6.25 °F2026-08-28: -6.94 °F2026-08-29: -2.24 °F2026-08-30: -0.83 °F2026-08-022026-08-30°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 (29 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-0.83
2026-08-29-2.24
2026-08-28-6.94
2026-08-27-6.25
2026-08-26-1.48
2026-08-25-2.35
2026-08-24-2.72
2026-08-23-3.38
2026-08-22-3.29
2026-08-21-2.11
2026-08-20-2.51
2026-08-19-1.62
2026-08-18-2.58
2026-08-17-3.11
2026-08-16-1.88
2026-08-15-3.03
2026-08-14-3.99
2026-08-13-4.23
2026-08-12-2.82
2026-08-11-1.18
2026-08-10-6.50
2026-08-09-5.17
2026-08-08-1.16
2026-08-07-3.09
2026-08-06-3.12
2026-08-05-1.45
2026-08-04-1.96
2026-08-03-3.51
2026-08-02-5.83

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KSAT, lead day 1-10 to -9 °F: 0 days-9 to -8 °F: 0 days-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: 8 days-3 to -2 °F: 7 days-2 to -1 °F: 7 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| 2.82 · P90 |e| 5.92 °F-100+10 °Fn = 29 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
-7.00-6.003
-6.00-5.002
-5.00-4.001
-4.00-3.008
-3.00-2.007
-2.00-1.007
-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
2026-08293.12 -3.12

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-02 → 2026-08-30 29
ECMWF AIFS Single2026-08-02 → 2026-08-30 29
ECMWF AIFS Single2026-08-02 → 2026-08-30 29
ECMWF AIFS Single2026-08-02 → 2026-08-30 29

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
Aurora (GFS init) 1 -6.99 [-6.99, -6.99] yes
Aurora (IFS init) 2 -4.52 [-5.32, -3.72] yes
FourCastNet v2 (GFS init) 1 -2.97 [-2.97, -2.97] yes
FourCastNet v2 (IFS init) 2 -1.19 [-1.82, -0.57] yes
NCEP GFS 29 +1.35 [0.51, 2.02] yes
GraphCast (GFS init) 1 -6.69 [-6.69, -6.69] yes
GraphCast (IFS init) 27 -2.86 [-3.74, -1.75] yes
ECMWF IFS HRES 23 +0.14 [-0.55, 1.50] no
Pangu-Weather (GFS init) 1 -2.34 [-2.34, -2.34] yes
Pangu-Weather (IFS init) 2 -2.41 [-2.85, -1.97] yes
Persistence (baseline) 29 +2.08 [1.59, 2.72] yes

Cite this page

ShortCastCheck, KSAT aifs_single lead 1, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KSAT/model/aifs_single/lead/1/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSAT (San Antonio Intl), model aifs_single, lead day 1. 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/1/

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

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