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

Austin Bergstrom · ECMWF AIFS Single · lead day 9

KAUS · 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 QC4.92 [3.13, 6.46]2.50-4.81 [-6.46, -2.88]5.75 [3.89, 7.09]14% [0%, 33%]14%24%-1.11-0.332026-08-10 → 2026-08-30
tmax00Zbilinear90d21 1 QC4.92 [2.52, 6.63]2.50-4.81 [-6.63, -2.23]5.75 [2.88, 7.16]14% [0%, 40%]14%24%-1.11-0.332026-08-10 → 2026-08-30
tmax00Zbilinear365d21 1 QC4.92 [2.71, 6.74]2.50-4.81 [-6.72, -2.50]5.75 [2.88, 7.27]14% [0%, 37%]14%24%-1.11-0.332026-08-10 → 2026-08-30
tmax00Zbilinearall21 1 QC4.92 [2.54, 6.85]2.50-4.81 [-6.85, -2.38]5.75 [2.86, 7.43]14% [0%, 39%]14%24%-1.11-0.332026-08-10 → 2026-08-30
tmax00Znearest30d21 1 QC5.17 [3.31, 6.80]2.51-5.11 [-6.79, -3.15]6.02 [4.14, 7.39]10% [0%, 19%]14%19%-1.22-0.332026-08-10 → 2026-08-30
tmax00Znearest90d21 1 QC5.17 [2.76, 6.98]2.51-5.11 [-6.98, -2.58]6.02 [3.19, 7.46]10% [0%, 20%]14%19%-1.22-0.332026-08-10 → 2026-08-30
tmax00Znearest365d21 1 QC5.17 [2.88, 7.09]2.51-5.11 [-7.08, -2.83]6.02 [3.19, 7.57]10% [0%, 20%]14%19%-1.22-0.332026-08-10 → 2026-08-30
tmax00Znearestall21 1 QC5.17 [2.79, 7.20]2.51-5.11 [-7.20, -2.72]6.02 [3.16, 7.73]10% [0%, 20%]14%19%-1.22-0.332026-08-10 → 2026-08-30
tmax12Zbilinear30d21 1 QC5.11 [3.19, 6.68]2.07-5.11 [-6.68, -3.19]5.81 [3.47, 7.19]10% [0%, 19%]14%19%-1.19-0.102026-08-10 → 2026-08-30
tmax12Zbilinear90d21 1 QC5.11 [3.00, 6.82]2.07-5.11 [-6.82, -3.00]5.81 [3.28, 7.35]10% [0%, 20%]14%19%-1.19-0.102026-08-10 → 2026-08-30
tmax12Zbilinear365d21 1 QC5.11 [3.07, 6.90]2.07-5.11 [-6.90, -3.07]5.81 [3.32, 7.40]10% [0%, 20%]14%19%-1.19-0.102026-08-10 → 2026-08-30
tmax12Zbilinearall21 1 QC5.11 [3.09, 6.78]2.07-5.11 [-6.78, -3.09]5.81 [3.34, 7.41]10% [0%, 20%]14%19%-1.19-0.102026-08-10 → 2026-08-30
tmax12Znearest30d21 1 QC5.37 [3.46, 6.92]2.09-5.37 [-6.92, -3.46]6.03 [3.70, 7.43]5% [0%, 14%]10%14%-1.30-0.112026-08-10 → 2026-08-30
tmax12Znearest90d21 1 QC5.37 [3.27, 7.06]2.09-5.37 [-7.06, -3.27]6.03 [3.51, 7.58]5% [0%, 18%]10%14%-1.30-0.112026-08-10 → 2026-08-30
tmax12Znearest365d21 1 QC5.37 [3.31, 7.14]2.09-5.37 [-7.14, -3.31]6.03 [3.52, 7.65]5% [0%, 17%]10%14%-1.30-0.112026-08-10 → 2026-08-30
tmax12Znearestall21 1 QC5.37 [3.34, 7.08]2.09-5.37 [-7.08, -3.34]6.03 [3.56, 7.66]5% [0%, 17%]10%14%-1.30-0.112026-08-10 → 2026-08-30
tmin00Zbilinear30d21 1 QC3.27 [1.97, 4.46]1.80+3.23 [1.86, 4.46]3.98 [2.55, 5.11]14% [0%, 26%]33%48%-0.14+0.372026-08-10 → 2026-08-30
tmin00Zbilinear90d21 1 QC3.27 [1.73, 4.69]1.80+3.23 [1.69, 4.69]3.98 [1.90, 5.39]14% [0%, 27%]33%48%-0.14+0.372026-08-10 → 2026-08-30
tmin00Zbilinear365d21 1 QC3.27 [1.81, 4.73]1.80+3.23 [1.73, 4.73]3.98 [1.95, 5.47]14% [0%, 27%]33%48%-0.14+0.372026-08-10 → 2026-08-30
tmin00Zbilinearall21 1 QC3.27 [1.76, 4.73]1.80+3.23 [1.70, 4.73]3.98 [1.89, 5.48]14% [0%, 29%]33%48%-0.14+0.372026-08-10 → 2026-08-30
tmin00Znearest30d21 1 QC3.01 [1.72, 4.21]1.84+2.94 [1.54, 4.21]3.78 [2.31, 4.95]19% [0%, 39%]43%52%-0.05+0.352026-08-10 → 2026-08-30
tmin00Znearest90d21 1 QC3.01 [1.47, 4.45]1.84+2.94 [1.37, 4.45]3.78 [1.62, 5.20]19% [0%, 41%]43%52%-0.05+0.352026-08-10 → 2026-08-30
tmin00Znearest365d21 1 QC3.01 [1.53, 4.51]1.84+2.94 [1.41, 4.51]3.78 [1.64, 5.29]19% [0%, 42%]43%52%-0.05+0.352026-08-10 → 2026-08-30
tmin00Znearestall21 1 QC3.01 [1.53, 4.52]1.84+2.94 [1.39, 4.52]3.78 [1.62, 5.32]19% [0%, 43%]43%52%-0.05+0.352026-08-10 → 2026-08-30
tmin12Zbilinear30d21 1 QC3.02 [1.80, 3.87]1.59+2.96 [1.66, 3.87]3.54 [2.41, 4.16]24% [0%, 50%]29%52%-0.06+0.442026-08-10 → 2026-08-30
tmin12Zbilinear90d21 1 QC3.02 [1.50, 3.86]1.59+2.96 [1.37, 3.86]3.54 [1.58, 4.13]24% [0%, 53%]29%52%-0.06+0.442026-08-10 → 2026-08-30
tmin12Zbilinear365d21 1 QC3.02 [1.58, 4.02]1.59+2.96 [1.44, 4.02]3.54 [1.74, 4.31]24% [0%, 55%]29%52%-0.06+0.442026-08-10 → 2026-08-30
tmin12Zbilinearall21 1 QC3.02 [1.55, 3.88]1.59+2.96 [1.41, 3.88]3.54 [1.66, 4.17]24% [0%, 57%]29%52%-0.06+0.442026-08-10 → 2026-08-30
tmin12Znearest30d21 1 QC2.83 [1.64, 3.67]1.63+2.72 [1.39, 3.65]3.36 [2.24, 3.97]24% [0%, 50%]29%57%+0.01+0.432026-08-10 → 2026-08-30
tmin12Znearest90d21 1 QC2.83 [1.34, 3.62]1.63+2.72 [1.09, 3.62]3.36 [1.37, 3.93]24% [0%, 53%]29%57%+0.01+0.432026-08-10 → 2026-08-30
tmin12Znearest365d21 1 QC2.83 [1.35, 3.74]1.63+2.72 [1.16, 3.74]3.36 [1.49, 4.06]24% [0%, 55%]29%57%+0.01+0.432026-08-10 → 2026-08-30
tmin12Znearestall21 1 QC2.83 [1.34, 3.67]1.63+2.72 [1.12, 3.66]3.36 [1.46, 3.95]24% [0%, 57%]29%57%+0.01+0.432026-08-10 → 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 KAUS, lead day 9, 00Z bilinear tmax+20+100-10-202026-08-10: -2.08 °F2026-08-11: -9.78 °F2026-08-12: -3.13 °F2026-08-13: -3 °F2026-08-14: +0.44 °F2026-08-15: -5.36 °F2026-08-16: -4.88 °F2026-08-17: -4.67 °F2026-08-18: -3.61 °F2026-08-19: -8.42 °F2026-08-20: -5.13 °F2026-08-21: -4.26 °F2026-08-22: -9.76 °F2026-08-23: -8.1 °F2026-08-24: -10.84 °F2026-08-25: -7.26 °F2026-08-26: -3.5 °F2026-08-27: -4.08 °F2026-08-28: +0.74 °F2026-08-29: -0.96 °F2026-08-30: -3.33 °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
2026-08-30-3.33
2026-08-29-0.96
2026-08-28+0.74
2026-08-27-4.08
2026-08-26-3.50
2026-08-25-7.26
2026-08-24-10.84
2026-08-23-8.10
2026-08-22-9.76
2026-08-21-4.26
2026-08-20-5.13
2026-08-19-8.42
2026-08-18-3.61
2026-08-17-4.67
2026-08-16-4.88
2026-08-15-5.36
2026-08-14+0.44
2026-08-13-3.00
2026-08-12-3.13
2026-08-11-9.78
2026-08-10-2.08

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KAUS, lead day 9-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 0 days-12 to -10 °F: 1 day-10 to -8 °F: 4 days-8 to -6 °F: 1 day-6 to -4 °F: 6 days-4 to -2 °F: 6 days-2 to 0 °F: 1 day0 to 2 °F: 2 days2 to 4 °F: 0 days4 to 6 °F: 0 days6 to 8 °F: 0 days8 to 10 °F: 0 days10 to 12 °F: 0 days12 to 14 °F: 0 days14 to 16 °F: 0 days16 to 18 °F: 0 days18 to 20 °F: 0 daysdashed: P50 |e| 4.26 · P90 |e| 9.76 °F-200+20 °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
-20.00-18.000
-18.00-16.000
-16.00-14.000
-14.00-12.000
-12.00-10.001
-10.00-8.004
-8.00-6.001
-6.00-4.006
-4.00-2.006
-2.00+0.001
+0.00+2.002
+2.00+4.000
+4.00+6.000
+6.00+8.000
+8.00+10.000
+10.00+12.000
+12.00+14.000
+14.00+16.000
+16.00+18.000
+18.00+20.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08214.92 -4.81

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 +2.25 [0.14, 3.81] yes
GraphCast (IFS init) 21 -2.57 [-3.94, -1.37] yes
ECMWF IFS HRES 16 +1.01 [-1.07, 2.00] no
Persistence (baseline) 21 +2.59 [0.32, 3.91] yes

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KAUS (Austin Bergstrom), 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/KAUS/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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