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

San Antonio Intl · ECMWF AIFS Single · lead day 0

KSAT · aifs_single · lead 0

Target day = initialization date + 0 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
tmax00Zbilinear30d30 1 QC3.19 [2.70, 3.65]1.29-3.19 [-3.65, -2.70]3.56 [2.91, 4.10]3% [0%, 10%]27%57%——2026-08-01 → 2026-08-30
tmax00Zbilinear90d30 1 QC3.19 [2.70, 3.81]1.29-3.19 [-3.81, -2.70]3.56 [2.93, 4.14]3% [0%, 13%]27%57%——2026-08-01 → 2026-08-30
tmax00Zbilinear365d30 1 QC3.19 [2.62, 3.71]1.29-3.19 [-3.71, -2.62]3.56 [2.83, 4.14]3% [0%, 16%]27%57%——2026-08-01 → 2026-08-30
tmax00Zbilinearall30 1 QC3.19 [2.60, 3.75]1.29-3.19 [-3.75, -2.60]3.56 [2.85, 4.13]3% [0%, 15%]27%57%——2026-08-01 → 2026-08-30
tmax00Znearest30d30 1 QC2.77 [2.26, 3.25]1.33-2.77 [-3.24, -2.26]3.21 [2.51, 3.78]3% [0%, 10%]40%70%——2026-08-01 → 2026-08-30
tmax00Znearest90d30 1 QC2.77 [2.26, 3.39]1.33-2.77 [-3.39, -2.26]3.21 [2.55, 3.81]3% [0%, 13%]40%70%——2026-08-01 → 2026-08-30
tmax00Znearest365d30 1 QC2.77 [2.18, 3.30]1.33-2.77 [-3.30, -2.18]3.21 [2.45, 3.82]3% [0%, 16%]40%70%——2026-08-01 → 2026-08-30
tmax00Znearestall30 1 QC2.77 [2.17, 3.34]1.33-2.77 [-3.34, -2.16]3.21 [2.46, 3.80]3% [0%, 15%]40%70%——2026-08-01 → 2026-08-30
tmin00Zbilinear30d30 1 QC1.49 [1.25, 1.74]1.13-0.90 [-1.53, -0.21]1.75 [1.47, 1.98]30% [20%, 40%]73%90%——2026-08-01 → 2026-08-30
tmin00Zbilinear90d30 1 QC1.49 [1.18, 1.75]1.13-0.90 [-1.58, -0.13]1.75 [1.39, 2.03]30% [18%, 43%]73%90%——2026-08-01 → 2026-08-30
tmin00Zbilinear365d30 1 QC1.49 [1.18, 1.78]1.13-0.90 [-1.60, -0.12]1.75 [1.40, 2.05]30% [17%, 44%]73%90%——2026-08-01 → 2026-08-30
tmin00Zbilinearall30 1 QC1.49 [1.16, 1.78]1.13-0.90 [-1.61, -0.10]1.75 [1.39, 2.05]30% [17%, 43%]73%90%——2026-08-01 → 2026-08-30
tmin00Znearest30d30 1 QC1.35 [1.07, 1.60]1.13-0.67 [-1.31, 0.03]1.66 [1.34, 1.88]40% [27%, 53%]80%93%——2026-08-01 → 2026-08-30
tmin00Znearest90d30 1 QC1.35 [1.01, 1.63]1.13-0.67 [-1.36, 0.11]1.66 [1.24, 1.95]40% [25%, 56%]80%93%——2026-08-01 → 2026-08-30
tmin00Znearest365d30 1 QC1.35 [1.03, 1.65]1.13-0.67 [-1.38, 0.13]1.66 [1.26, 1.96]40% [25%, 57%]80%93%——2026-08-01 → 2026-08-30
tmin00Znearestall30 1 QC1.35 [0.99, 1.64]1.13-0.67 [-1.38, 0.13]1.66 [1.24, 1.94]40% [25%, 57%]80%93%——2026-08-01 → 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 0, 00Z bilinear tmax+10+50-5-102026-08-01: -5.86 °F2026-08-02: -5.59 °F2026-08-03: -2.59 °F2026-08-04: -2.8 °F2026-08-05: -2.05 °F2026-08-06: -3.06 °F2026-08-07: -4.11 °F2026-08-08: -1.67 °F2026-08-09: -5.96 °F2026-08-10: -5.6 °F2026-08-11: -1.6 °F2026-08-12: -1.82 °F2026-08-13: -3.82 °F2026-08-14: -5.08 °F2026-08-15: -3.02 °F2026-08-16: -1.61 °F2026-08-17: -3.17 °F2026-08-18: -1.63 °F2026-08-19: -1.9 °F2026-08-20: -2.54 °F2026-08-21: -2.45 °F2026-08-22: -3.17 °F2026-08-23: -2.26 °F2026-08-24: -2.88 °F2026-08-25: -2.7 °F2026-08-26: -1.83 °F2026-08-27: -6.39 °F2026-08-28: -5.59 °F2026-08-29: -2.49 °F2026-08-30: -0.45 °F2026-08-012026-08-30°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 (30 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-0.45
2026-08-29-2.49
2026-08-28-5.59
2026-08-27-6.39
2026-08-26-1.83
2026-08-25-2.70
2026-08-24-2.88
2026-08-23-2.26
2026-08-22-3.17
2026-08-21-2.45
2026-08-20-2.54
2026-08-19-1.90
2026-08-18-1.63
2026-08-17-3.17
2026-08-16-1.61
2026-08-15-3.02
2026-08-14-5.08
2026-08-13-3.82
2026-08-12-1.82
2026-08-11-1.60
2026-08-10-5.60
2026-08-09-5.96
2026-08-08-1.67
2026-08-07-4.11
2026-08-06-3.06
2026-08-05-2.05
2026-08-04-2.80
2026-08-03-2.59
2026-08-02-5.59
2026-08-01-5.86

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KSAT, lead day 0-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 1 day-6 to -5 °F: 6 days-5 to -4 °F: 1 day-4 to -3 °F: 5 days-3 to -2 °F: 9 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| 2.75 · P90 |e| 5.62 °F-100+10 °Fn = 30 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
-7.00-6.001
-6.00-5.006
-5.00-4.001
-4.00-3.005
-3.00-2.009
-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
2026-08303.19 -3.19

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-01 → 2026-08-30 30
ECMWF AIFS Single2026-08-01 → 2026-08-30 30

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) 2 -5.86 [-6.94, -4.78] yes
Aurora (IFS init) 3 -3.44 [-4.26, -1.81] yes
FourCastNet v2 (GFS init) 2 -2.88 [-3.45, -2.30] yes
FourCastNet v2 (IFS init) 3 -1.37 [-1.77, -0.58] yes
NCEP GFS 30 +1.08 [0.35, 1.89] yes
GraphCast (GFS init) 2 -5.20 [-5.73, -4.67] yes
GraphCast (IFS init) 28 -2.33 [-3.04, -1.37] yes
ECMWF IFS HRES 24 -0.09 [-0.51, 0.54] no
Pangu-Weather (GFS init) 2 -1.56 [-2.21, -0.92] yes
Pangu-Weather (IFS init) 3 +0.12 [-1.88, 2.61] no

Cite this page

ShortCastCheck, KSAT aifs_single lead 0, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KSAT/model/aifs_single/lead/0/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSAT (San Antonio Intl), model aifs_single, lead day 0. 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/0/

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

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