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

San Antonio Intl · ECMWF AIFS Single · lead day 2

KSAT · aifs_single · lead 2

Target day = initialization date + 2 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
tmax00Zbilinear30d28 1 QC3.10 [2.67, 3.53]1.16-3.10 [-3.53, -2.67]3.46 [2.84, 4.05]4% [0%, 12%]29%57%-1.12+0.222026-08-03 → 2026-08-30
tmax00Zbilinear90d28 1 QC3.10 [2.62, 3.51]1.16-3.10 [-3.51, -2.62]3.46 [2.79, 4.04]4% [0%, 14%]29%57%-1.12+0.222026-08-03 → 2026-08-30
tmax00Zbilinear365d28 1 QC3.10 [2.62, 3.55]1.16-3.10 [-3.55, -2.62]3.46 [2.77, 4.12]4% [0%, 17%]29%57%-1.12+0.222026-08-03 → 2026-08-30
tmax00Zbilinearall28 1 QC3.10 [2.59, 3.52]1.16-3.10 [-3.52, -2.59]3.46 [2.77, 4.07]4% [0%, 17%]29%57%-1.12+0.222026-08-03 → 2026-08-30
tmax00Znearest30d28 1 QC2.68 [2.23, 3.12]1.19-2.68 [-3.12, -2.23]3.11 [2.43, 3.73]4% [0%, 12%]36%64%-0.83+0.202026-08-03 → 2026-08-30
tmax00Znearest90d28 1 QC2.68 [2.19, 3.09]1.19-2.68 [-3.09, -2.19]3.11 [2.38, 3.75]4% [0%, 14%]36%64%-0.83+0.202026-08-03 → 2026-08-30
tmax00Znearest365d28 1 QC2.68 [2.19, 3.14]1.19-2.68 [-3.14, -2.19]3.11 [2.37, 3.83]4% [0%, 17%]36%64%-0.83+0.202026-08-03 → 2026-08-30
tmax00Znearestall28 1 QC2.68 [2.15, 3.11]1.19-2.68 [-3.11, -2.15]3.11 [2.35, 3.76]4% [0%, 17%]36%64%-0.83+0.202026-08-03 → 2026-08-30
tmax12Zbilinear30d28 1 QC3.54 [3.19, 3.92]1.10-3.54 [-3.92, -3.19]3.80 [3.31, 4.26]0% [0%, 0%]14%46%-1.42+0.262026-08-03 → 2026-08-30
tmax12Zbilinear90d28 1 QC3.54 [3.16, 3.90]1.10-3.54 [-3.90, -3.16]3.80 [3.29, 4.27]0% [0%, 0%]14%46%-1.42+0.262026-08-03 → 2026-08-30
tmax12Zbilinear365d28 1 QC3.54 [3.13, 3.90]1.10-3.54 [-3.90, -3.13]3.80 [3.25, 4.30]0% [0%, 0%]14%46%-1.42+0.262026-08-03 → 2026-08-30
tmax12Zbilinearall28 1 QC3.54 [3.12, 3.90]1.10-3.54 [-3.90, -3.12]3.80 [3.26, 4.29]0% [0%, 0%]14%46%-1.42+0.262026-08-03 → 2026-08-30
tmax12Znearest30d28 1 QC3.11 [2.75, 3.50]1.12-3.11 [-3.50, -2.75]3.42 [2.90, 3.93]0% [0%, 0%]18%54%-1.13+0.242026-08-03 → 2026-08-30
tmax12Znearest90d28 1 QC3.11 [2.72, 3.48]1.12-3.11 [-3.48, -2.72]3.42 [2.87, 3.92]0% [0%, 0%]18%54%-1.13+0.242026-08-03 → 2026-08-30
tmax12Znearest365d28 1 QC3.11 [2.68, 3.48]1.12-3.11 [-3.48, -2.68]3.42 [2.83, 3.97]0% [0%, 0%]18%54%-1.13+0.242026-08-03 → 2026-08-30
tmax12Znearestall28 1 QC3.11 [2.69, 3.50]1.12-3.11 [-3.50, -2.69]3.42 [2.83, 3.95]0% [0%, 0%]18%54%-1.13+0.242026-08-03 → 2026-08-30
tmin00Zbilinear30d28 1 QC1.64 [1.43, 1.86]1.36-0.82 [-1.71, 0.25]1.87 [1.60, 2.13]25% [15%, 38%]71%89%-0.02+0.172026-08-03 → 2026-08-30
tmin00Zbilinear90d28 1 QC1.64 [1.43, 1.89]1.36-0.82 [-1.74, 0.27]1.87 [1.57, 2.16]25% [13%, 38%]71%89%-0.02+0.172026-08-03 → 2026-08-30
tmin00Zbilinear365d28 1 QC1.64 [1.41, 1.89]1.36-0.82 [-1.75, 0.43]1.87 [1.55, 2.18]25% [14%, 43%]71%89%-0.02+0.172026-08-03 → 2026-08-30
tmin00Zbilinearall28 1 QC1.64 [1.37, 1.91]1.36-0.82 [-1.76, 0.43]1.87 [1.51, 2.19]25% [13%, 39%]71%89%-0.02+0.172026-08-03 → 2026-08-30
tmin00Znearest30d28 1 QC1.55 [1.35, 1.77]1.36-0.58 [-1.48, 0.51]1.79 [1.51, 2.04]25% [17%, 32%]71%89%+0.03+0.162026-08-03 → 2026-08-30
tmin00Znearest90d28 1 QC1.55 [1.32, 1.81]1.36-0.58 [-1.51, 0.52]1.79 [1.43, 2.09]25% [14%, 33%]71%89%+0.03+0.162026-08-03 → 2026-08-30
tmin00Znearest365d28 1 QC1.55 [1.33, 1.81]1.36-0.58 [-1.52, 0.68]1.79 [1.46, 2.10]25% [14%, 33%]71%89%+0.03+0.162026-08-03 → 2026-08-30
tmin00Znearestall28 1 QC1.55 [1.31, 1.80]1.36-0.58 [-1.53, 0.68]1.79 [1.44, 2.10]25% [14%, 33%]71%89%+0.03+0.162026-08-03 → 2026-08-30
tmin12Zbilinear30d28 1 QC1.56 [1.20, 1.87]1.22-1.03 [-1.77, -0.11]1.87 [1.49, 2.19]36% [19%, 53%]71%89%+0.03+0.252026-08-03 → 2026-08-30
tmin12Zbilinear90d28 1 QC1.56 [1.21, 1.88]1.22-1.03 [-1.82, -0.14]1.87 [1.48, 2.24]36% [17%, 53%]71%89%+0.03+0.252026-08-03 → 2026-08-30
tmin12Zbilinear365d28 1 QC1.56 [1.17, 1.89]1.22-1.03 [-1.84, -0.02]1.87 [1.45, 2.25]36% [14%, 56%]71%89%+0.03+0.252026-08-03 → 2026-08-30
tmin12Zbilinearall28 1 QC1.56 [1.09, 1.90]1.22-1.03 [-1.85, -0.01]1.87 [1.39, 2.24]36% [14%, 57%]71%89%+0.03+0.252026-08-03 → 2026-08-30
tmin12Znearest30d28 1 QC1.46 [1.20, 1.71]1.22-0.80 [-1.54, 0.12]1.76 [1.45, 2.06]43% [25%, 61%]79%86%+0.09+0.252026-08-03 → 2026-08-30
tmin12Znearest90d28 1 QC1.46 [1.20, 1.72]1.22-0.80 [-1.59, 0.11]1.76 [1.42, 2.09]43% [25%, 61%]79%86%+0.09+0.252026-08-03 → 2026-08-30
tmin12Znearest365d28 1 QC1.46 [1.18, 1.76]1.22-0.80 [-1.63, 0.22]1.76 [1.39, 2.14]43% [23%, 64%]79%86%+0.09+0.252026-08-03 → 2026-08-30
tmin12Znearestall28 1 QC1.46 [1.14, 1.75]1.22-0.80 [-1.63, 0.23]1.76 [1.34, 2.13]43% [22%, 67%]79%86%+0.09+0.252026-08-03 → 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 2, 00Z bilinear tmax+10+50-5-102026-08-03: -3.66 °F2026-08-04: -2.84 °F2026-08-05: -1.78 °F2026-08-06: -2.78 °F2026-08-07: -2.78 °F2026-08-08: -1.49 °F2026-08-09: -4.6 °F2026-08-10: -3.79 °F2026-08-11: -2.33 °F2026-08-12: -1.92 °F2026-08-13: -4.91 °F2026-08-14: -5.82 °F2026-08-15: -3.63 °F2026-08-16: -1.63 °F2026-08-17: -3.06 °F2026-08-18: -3.05 °F2026-08-19: -2.84 °F2026-08-20: -2.47 °F2026-08-21: -2.09 °F2026-08-22: -3.61 °F2026-08-23: -3.69 °F2026-08-24: -2.76 °F2026-08-25: -1.94 °F2026-08-26: -1.57 °F2026-08-27: -5.61 °F2026-08-28: -7.92 °F2026-08-29: -1.7 °F2026-08-30: -0.51 °F2026-08-032026-08-30°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 (28 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-0.51
2026-08-29-1.70
2026-08-28-7.92
2026-08-27-5.61
2026-08-26-1.57
2026-08-25-1.94
2026-08-24-2.76
2026-08-23-3.69
2026-08-22-3.61
2026-08-21-2.09
2026-08-20-2.47
2026-08-19-2.84
2026-08-18-3.05
2026-08-17-3.06
2026-08-16-1.63
2026-08-15-3.63
2026-08-14-5.82
2026-08-13-4.91
2026-08-12-1.92
2026-08-11-2.33
2026-08-10-3.79
2026-08-09-4.60
2026-08-08-1.49
2026-08-07-2.78
2026-08-06-2.78
2026-08-05-1.78
2026-08-04-2.84
2026-08-03-3.66

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KSAT, lead day 2-10 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: 2 days-5 to -4 °F: 2 days-4 to -3 °F: 7 days-3 to -2 °F: 8 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| 2.81 · P90 |e| 5.12 °F-100+10 °Fn = 28 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
-6.00-5.002
-5.00-4.002
-4.00-3.007
-3.00-2.008
-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
2026-08283.10 -3.10

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-03 → 2026-08-30 28
ECMWF AIFS Single2026-08-03 → 2026-08-30 28
ECMWF AIFS Single2026-08-03 → 2026-08-30 28
ECMWF AIFS Single2026-08-03 → 2026-08-30 28

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 (IFS init) 1 -4.13 [-4.13, -4.13] yes
FourCastNet v2 (IFS init) 1 -1.16 [-1.16, -1.16] yes
NCEP GFS 28 +1.33 [0.73, 1.86] yes
GraphCast (IFS init) 26 -2.72 [-3.60, -1.61] yes
ECMWF IFS HRES 22 +0.09 [-0.60, 0.95] no
Pangu-Weather (IFS init) 1 -3.69 [-3.69, -3.69] yes
Persistence (baseline) 28 +1.63 [1.04, 2.08] yes

Cite this page

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

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

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