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

San Antonio Intl · ECMWF AIFS Single · lead day 8

KSAT · 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 QC2.73 [1.62, 3.82]1.63-2.73 [-3.82, -1.62]3.36 [2.02, 4.39]14% [0%, 28%]50%68%-0.25+0.172026-08-09 → 2026-08-30
tmax00Zbilinear90d22 1 QC2.73 [1.47, 3.95]1.63-2.73 [-3.95, -1.47]3.36 [1.79, 4.43]14% [0%, 32%]50%68%-0.25+0.172026-08-09 → 2026-08-30
tmax00Zbilinear365d22 1 QC2.73 [1.27, 3.97]1.63-2.73 [-3.97, -1.27]3.36 [1.43, 4.55]14% [0%, 33%]50%68%-0.25+0.172026-08-09 → 2026-08-30
tmax00Zbilinearall22 1 QC2.73 [1.27, 4.09]1.63-2.73 [-4.09, -1.27]3.36 [1.37, 4.63]14% [0%, 33%]50%68%-0.25+0.172026-08-09 → 2026-08-30
tmax00Znearest30d22 1 QC2.35 [1.27, 3.43]1.65-2.32 [-3.42, -1.21]3.06 [1.70, 4.07]36% [14%, 67%]55%68%-0.08+0.162026-08-09 → 2026-08-30
tmax00Znearest90d22 1 QC2.35 [1.08, 3.55]1.65-2.32 [-3.55, -1.05]3.06 [1.47, 4.11]36% [11%, 75%]55%68%-0.08+0.162026-08-09 → 2026-08-30
tmax00Znearest365d22 1 QC2.35 [0.89, 3.66]1.65-2.32 [-3.57, -0.87]3.06 [1.07, 4.23]36% [9%, 73%]55%68%-0.08+0.162026-08-09 → 2026-08-30
tmax00Znearestall22 1 QC2.35 [0.94, 3.70]1.65-2.32 [-3.69, -0.87]3.06 [1.04, 4.30]36% [7%, 79%]55%68%-0.08+0.162026-08-09 → 2026-08-30
tmax12Zbilinear30d22 1 QC3.02 [2.11, 3.55]1.12-3.02 [-3.55, -2.11]3.31 [2.50, 3.78]9% [0%, 27%]18%50%-0.38+0.432026-08-09 → 2026-08-30
tmax12Zbilinear90d22 1 QC3.02 [2.07, 3.64]1.12-3.02 [-3.64, -2.07]3.31 [2.47, 3.83]9% [0%, 31%]18%50%-0.38+0.432026-08-09 → 2026-08-30
tmax12Zbilinear365d22 1 QC3.02 [2.01, 3.63]1.12-3.02 [-3.63, -2.01]3.31 [2.44, 3.83]9% [0%, 33%]18%50%-0.38+0.432026-08-09 → 2026-08-30
tmax12Zbilinearall22 1 QC3.02 [1.93, 3.63]1.12-3.02 [-3.63, -1.93]3.31 [2.39, 3.89]9% [0%, 33%]18%50%-0.38+0.432026-08-09 → 2026-08-30
tmax12Znearest30d22 1 QC2.61 [1.71, 3.14]1.12-2.61 [-3.14, -1.71]2.94 [2.16, 3.40]14% [0%, 40%]36%68%-0.19+0.432026-08-09 → 2026-08-30
tmax12Znearest90d22 1 QC2.61 [1.66, 3.22]1.12-2.61 [-3.22, -1.66]2.94 [2.11, 3.45]14% [0%, 50%]36%68%-0.19+0.432026-08-09 → 2026-08-30
tmax12Znearest365d22 1 QC2.61 [1.60, 3.21]1.12-2.61 [-3.21, -1.60]2.94 [2.07, 3.45]14% [0%, 50%]36%68%-0.19+0.432026-08-09 → 2026-08-30
tmax12Znearestall22 1 QC2.61 [1.53, 3.22]1.12-2.61 [-3.22, -1.53]2.94 [2.03, 3.50]14% [0%, 56%]36%68%-0.19+0.432026-08-09 → 2026-08-30
tmin00Zbilinear30d22 1 QC1.61 [1.12, 2.41]1.58-0.08 [-1.25, 1.00]2.17 [1.27, 3.19]50% [24%, 70%]77%91%+0.09+0.142026-08-09 → 2026-08-30
tmin00Zbilinear90d22 1 QC1.61 [1.12, 2.67]1.58-0.08 [-1.46, 1.23]2.17 [1.27, 3.51]50% [11%, 70%]77%91%+0.09+0.142026-08-09 → 2026-08-30
tmin00Zbilinear365d22 1 QC1.61 [1.06, 2.58]1.58-0.08 [-1.48, 1.19]2.17 [1.21, 3.35]50% [0%, 71%]77%91%+0.09+0.142026-08-09 → 2026-08-30
tmin00Zbilinearall22 1 QC1.61 [1.10, 2.66]1.58-0.08 [-1.46, 1.26]2.17 [1.21, 3.34]50% [0%, 71%]77%91%+0.09+0.142026-08-09 → 2026-08-30
tmin00Znearest30d22 1 QC1.52 [0.93, 2.38]1.59+0.15 [-1.02, 1.25]2.19 [1.11, 3.24]50% [24%, 70%]77%91%+0.14+0.132026-08-09 → 2026-08-30
tmin00Znearest90d22 1 QC1.52 [0.93, 2.68]1.59+0.15 [-1.23, 1.48]2.19 [1.11, 3.57]50% [11%, 70%]77%91%+0.14+0.132026-08-09 → 2026-08-30
tmin00Znearest365d22 1 QC1.52 [0.91, 2.58]1.59+0.15 [-1.25, 1.43]2.19 [1.05, 3.44]50% [0%, 71%]77%91%+0.14+0.132026-08-09 → 2026-08-30
tmin00Znearestall22 1 QC1.52 [0.91, 2.61]1.59+0.15 [-1.23, 1.50]2.19 [1.03, 3.44]50% [0%, 71%]77%91%+0.14+0.132026-08-09 → 2026-08-30
tmin12Zbilinear30d22 1 QC1.68 [1.22, 2.46]1.49-0.66 [-1.54, 0.13]2.09 [1.46, 2.91]32% [6%, 55%]68%91%+0.05+0.192026-08-09 → 2026-08-30
tmin12Zbilinear90d22 1 QC1.68 [1.18, 2.65]1.49-0.66 [-1.79, 0.28]2.09 [1.41, 3.09]32% [0%, 57%]68%91%+0.05+0.192026-08-09 → 2026-08-30
tmin12Zbilinear365d22 1 QC1.68 [1.14, 2.69]1.49-0.66 [-1.80, 0.24]2.09 [1.40, 3.05]32% [0%, 58%]68%91%+0.05+0.192026-08-09 → 2026-08-30
tmin12Zbilinearall22 1 QC1.68 [1.18, 2.70]1.49-0.66 [-1.79, 0.22]2.09 [1.40, 3.05]32% [0%, 57%]68%91%+0.05+0.192026-08-09 → 2026-08-30
tmin12Znearest30d22 1 QC1.60 [1.12, 2.39]1.49-0.43 [-1.32, 0.36]2.03 [1.37, 2.92]41% [17%, 58%]73%95%+0.10+0.192026-08-09 → 2026-08-30
tmin12Znearest90d22 1 QC1.60 [1.08, 2.62]1.49-0.43 [-1.57, 0.52]2.03 [1.32, 3.16]41% [10%, 60%]73%95%+0.10+0.192026-08-09 → 2026-08-30
tmin12Znearest365d22 1 QC1.60 [1.05, 2.65]1.49-0.43 [-1.57, 0.49]2.03 [1.30, 3.03]41% [5%, 59%]73%95%+0.10+0.192026-08-09 → 2026-08-30
tmin12Znearestall22 1 QC1.60 [1.08, 2.68]1.49-0.43 [-1.57, 0.47]2.03 [1.32, 3.01]41% [0%, 60%]73%95%+0.10+0.192026-08-09 → 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 KSAT, lead day 8, 00Z bilinear tmax+10+50-5-102026-08-09: -2.23 °F2026-08-10: -5.66 °F2026-08-11: -1.12 °F2026-08-12: -1.31 °F2026-08-13: -2.75 °F2026-08-14: -1.07 °F2026-08-15: -3.95 °F2026-08-16: -1.84 °F2026-08-17: -1.48 °F2026-08-18: -0.81 °F2026-08-19: -2.92 °F2026-08-20: -4.13 °F2026-08-21: -4.18 °F2026-08-22: -5.15 °F2026-08-23: -7.34 °F2026-08-24: -6.44 °F2026-08-25: -2.58 °F2026-08-26: -1.96 °F2026-08-27: -0.12 °F2026-08-28: -1.06 °F2026-08-29: -0.58 °F2026-08-30: -1.34 °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
2026-08-30-1.34
2026-08-29-0.58
2026-08-28-1.06
2026-08-27-0.12
2026-08-26-1.96
2026-08-25-2.58
2026-08-24-6.44
2026-08-23-7.34
2026-08-22-5.15
2026-08-21-4.18
2026-08-20-4.13
2026-08-19-2.92
2026-08-18-0.81
2026-08-17-1.48
2026-08-16-1.84
2026-08-15-3.95
2026-08-14-1.07
2026-08-13-2.75
2026-08-12-1.31
2026-08-11-1.12
2026-08-10-5.66
2026-08-09-2.23

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KSAT, lead day 8-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 1 day-7 to -6 °F: 1 day-6 to -5 °F: 2 days-5 to -4 °F: 2 days-4 to -3 °F: 1 day-3 to -2 °F: 4 days-2 to -1 °F: 8 days-1 to 0 °F: 3 days0 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| 2.09 · P90 |e| 5.61 °F-100+10 °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
-10.00-9.000
-9.00-8.000
-8.00-7.001
-7.00-6.001
-6.00-5.002
-5.00-4.002
-4.00-3.001
-3.00-2.004
-2.00-1.008
-1.00+0.003
+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
2026-08222.73 -2.73

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 +0.75 [-0.71, 1.62] no
GraphCast (IFS init) 22 -3.16 [-3.91, -1.61] yes
ECMWF IFS HRES 17 -0.19 [-1.44, 1.21] no
Persistence (baseline) 22 +0.55 [-1.52, 2.00] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSAT (San Antonio Intl), 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/KSAT/model/aifs_single/lead/8/

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

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