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

Austin Bergstrom · ECMWF AIFS Single · lead day 2

KAUS · 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 QC5.30 [4.91, 5.68]1.13-5.30 [-5.68, -4.91]5.48 [5.14, 5.87]0% [0%, 0%]0%0%-1.97+0.372026-08-03 → 2026-08-30
tmax00Zbilinear90d28 1 QC5.30 [4.86, 5.74]1.13-5.30 [-5.74, -4.86]5.48 [5.09, 5.88]0% [0%, 0%]0%0%-1.97+0.372026-08-03 → 2026-08-30
tmax00Zbilinear365d28 1 QC5.30 [4.81, 5.74]1.13-5.30 [-5.74, -4.81]5.48 [5.05, 5.90]0% [0%, 0%]0%0%-1.97+0.372026-08-03 → 2026-08-30
tmax00Zbilinearall28 1 QC5.30 [4.73, 5.79]1.13-5.30 [-5.79, -4.73]5.48 [4.98, 5.92]0% [0%, 0%]0%0%-1.97+0.372026-08-03 → 2026-08-30
tmax00Znearest30d28 1 QC5.38 [5.02, 5.74]1.08-5.38 [-5.74, -5.02]5.55 [5.22, 5.91]0% [0%, 0%]0%0%-2.01+0.402026-08-03 → 2026-08-30
tmax00Znearest90d28 1 QC5.38 [4.97, 5.81]1.08-5.38 [-5.81, -4.97]5.55 [5.18, 5.94]0% [0%, 0%]0%0%-2.01+0.402026-08-03 → 2026-08-30
tmax00Znearest365d28 1 QC5.38 [4.92, 5.83]1.08-5.38 [-5.83, -4.92]5.55 [5.14, 5.97]0% [0%, 0%]0%0%-2.01+0.402026-08-03 → 2026-08-30
tmax00Znearestall28 1 QC5.38 [4.85, 5.88]1.08-5.38 [-5.88, -4.85]5.55 [5.08, 5.99]0% [0%, 0%]0%0%-2.01+0.402026-08-03 → 2026-08-30
tmax12Zbilinear30d28 1 QC5.65 [5.22, 6.13]1.08-5.65 [-6.13, -5.22]5.79 [5.38, 6.22]0% [0%, 0%]0%0%-2.17+0.402026-08-03 → 2026-08-30
tmax12Zbilinear90d28 1 QC5.65 [5.19, 6.29]1.08-5.65 [-6.29, -5.19]5.79 [5.36, 6.35]0% [0%, 0%]0%0%-2.17+0.402026-08-03 → 2026-08-30
tmax12Zbilinear365d28 1 QC5.65 [5.13, 6.24]1.08-5.65 [-6.24, -5.13]5.79 [5.31, 6.32]0% [0%, 0%]0%0%-2.17+0.402026-08-03 → 2026-08-30
tmax12Zbilinearall28 1 QC5.65 [5.08, 6.29]1.08-5.65 [-6.29, -5.08]5.79 [5.27, 6.36]0% [0%, 0%]0%0%-2.17+0.402026-08-03 → 2026-08-30
tmax12Znearest30d28 1 QC5.72 [5.30, 6.20]1.04-5.72 [-6.20, -5.30]5.84 [5.46, 6.29]0% [0%, 0%]0%0%-2.20+0.422026-08-03 → 2026-08-30
tmax12Znearest90d28 1 QC5.72 [5.26, 6.35]1.04-5.72 [-6.35, -5.26]5.84 [5.43, 6.41]0% [0%, 0%]0%0%-2.20+0.422026-08-03 → 2026-08-30
tmax12Znearest365d28 1 QC5.72 [5.21, 6.32]1.04-5.72 [-6.32, -5.21]5.84 [5.38, 6.40]0% [0%, 0%]0%0%-2.20+0.422026-08-03 → 2026-08-30
tmax12Znearestall28 1 QC5.72 [5.16, 6.38]1.04-5.72 [-6.38, -5.16]5.84 [5.35, 6.45]0% [0%, 0%]0%0%-2.20+0.422026-08-03 → 2026-08-30
tmin00Zbilinear30d28 1 QC2.95 [2.09, 3.72]1.72+2.70 [1.63, 3.61]3.40 [2.54, 4.10]14% [3%, 30%]36%54%+0.10+0.482026-08-03 → 2026-08-30
tmin00Zbilinear90d28 1 QC2.95 [2.08, 3.85]1.72+2.70 [1.63, 3.79]3.40 [2.56, 4.20]14% [0%, 31%]36%54%+0.10+0.482026-08-03 → 2026-08-30
tmin00Zbilinear365d28 1 QC2.95 [2.01, 3.95]1.72+2.70 [1.57, 3.95]3.40 [2.46, 4.28]14% [0%, 32%]36%54%+0.10+0.482026-08-03 → 2026-08-30
tmin00Zbilinearall28 1 QC2.95 [2.06, 4.02]1.72+2.70 [1.52, 4.02]3.40 [2.54, 4.33]14% [0%, 31%]36%54%+0.10+0.482026-08-03 → 2026-08-30
tmin00Znearest30d28 1 QC2.85 [1.99, 3.65]1.75+2.54 [1.42, 3.51]3.31 [2.45, 4.03]14% [3%, 30%]36%54%+0.13+0.472026-08-03 → 2026-08-30
tmin00Znearest90d28 1 QC2.85 [1.99, 3.77]1.75+2.54 [1.43, 3.71]3.31 [2.45, 4.11]14% [0%, 31%]36%54%+0.13+0.472026-08-03 → 2026-08-30
tmin00Znearest365d28 1 QC2.85 [1.92, 3.87]1.75+2.54 [1.36, 3.86]3.31 [2.36, 4.21]14% [0%, 32%]36%54%+0.13+0.472026-08-03 → 2026-08-30
tmin00Znearestall28 1 QC2.85 [1.98, 3.94]1.75+2.54 [1.28, 3.94]3.31 [2.43, 4.27]14% [0%, 31%]36%54%+0.13+0.472026-08-03 → 2026-08-30
tmin12Zbilinear30d28 1 QC2.79 [1.98, 3.44]1.53+2.51 [1.54, 3.32]3.15 [2.34, 3.76]7% [0%, 20%]32%57%+0.15+0.542026-08-03 → 2026-08-30
tmin12Zbilinear90d28 1 QC2.79 [2.00, 3.55]1.53+2.51 [1.53, 3.41]3.15 [2.35, 3.83]7% [0%, 21%]32%57%+0.15+0.542026-08-03 → 2026-08-30
tmin12Zbilinear365d28 1 QC2.79 [1.92, 3.58]1.53+2.51 [1.46, 3.55]3.15 [2.27, 3.89]7% [0%, 21%]32%57%+0.15+0.542026-08-03 → 2026-08-30
tmin12Zbilinearall28 1 QC2.79 [1.96, 3.61]1.53+2.51 [1.45, 3.61]3.15 [2.35, 3.92]7% [0%, 21%]32%57%+0.15+0.542026-08-03 → 2026-08-30
tmin12Znearest30d28 1 QC2.68 [1.88, 3.37]1.55+2.34 [1.31, 3.23]3.06 [2.23, 3.69]14% [0%, 36%]32%57%+0.18+0.532026-08-03 → 2026-08-30
tmin12Znearest90d28 1 QC2.68 [1.90, 3.47]1.55+2.34 [1.29, 3.32]3.06 [2.23, 3.77]14% [0%, 36%]32%57%+0.18+0.532026-08-03 → 2026-08-30
tmin12Znearest365d28 1 QC2.68 [1.82, 3.51]1.55+2.34 [1.24, 3.46]3.06 [2.16, 3.84]14% [0%, 39%]32%57%+0.18+0.532026-08-03 → 2026-08-30
tmin12Znearestall28 1 QC2.68 [1.87, 3.53]1.55+2.34 [1.21, 3.53]3.06 [2.24, 3.86]14% [0%, 37%]32%57%+0.18+0.532026-08-03 → 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 KAUS, lead day 2, 00Z bilinear tmax+10+50-5-102026-08-03: -6.29 °F2026-08-04: -6.63 °F2026-08-05: -4.9 °F2026-08-06: -6.03 °F2026-08-07: -5.73 °F2026-08-08: -5.29 °F2026-08-09: -6.77 °F2026-08-10: -5.55 °F2026-08-11: -5.09 °F2026-08-12: -4 °F2026-08-13: -5.66 °F2026-08-14: -5.11 °F2026-08-15: -6.56 °F2026-08-16: -4.98 °F2026-08-17: -6.63 °F2026-08-18: -5.01 °F2026-08-19: -4.19 °F2026-08-20: -3.44 °F2026-08-21: -3.92 °F2026-08-22: -7.55 °F2026-08-23: -5.13 °F2026-08-24: -4.46 °F2026-08-25: -3.86 °F2026-08-26: -3.28 °F2026-08-27: -6.8 °F2026-08-28: -9.11 °F2026-08-29: -3.28 °F2026-08-30: -3.01 °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
2026-08-30-3.01
2026-08-29-3.28
2026-08-28-9.11
2026-08-27-6.80
2026-08-26-3.28
2026-08-25-3.86
2026-08-24-4.46
2026-08-23-5.13
2026-08-22-7.55
2026-08-21-3.92
2026-08-20-3.44
2026-08-19-4.19
2026-08-18-5.01
2026-08-17-6.63
2026-08-16-4.98
2026-08-15-6.56
2026-08-14-5.11
2026-08-13-5.66
2026-08-12-4.00
2026-08-11-5.09
2026-08-10-5.55
2026-08-09-6.77
2026-08-08-5.29
2026-08-07-5.73
2026-08-06-6.03
2026-08-05-4.90
2026-08-04-6.63
2026-08-03-6.29

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KAUS, lead day 2-10 to -9 °F: 1 day-9 to -8 °F: 0 days-8 to -7 °F: 1 day-7 to -6 °F: 7 days-6 to -5 °F: 8 days-5 to -4 °F: 5 days-4 to -3 °F: 6 days-3 to -2 °F: 0 days-2 to -1 °F: 0 days-1 to 0 °F: 0 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| 5.12 · P90 |e| 6.78 °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
-10.00-9.001
-9.00-8.000
-8.00-7.001
-7.00-6.007
-6.00-5.008
-5.00-4.005
-4.00-3.006
-3.00-2.000
-2.00-1.000
-1.00+0.000
+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
2026-08285.30 -5.30

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 -3.61 [-3.61, -3.61] yes
FourCastNet v2 (IFS init) 1 -1.12 [-1.12, -1.12] yes
NCEP GFS 28 +3.75 [3.25, 4.26] yes
GraphCast (IFS init) 26 -2.15 [-3.01, -1.17] yes
ECMWF IFS HRES 22 +0.83 [0.31, 1.77] yes
Pangu-Weather (IFS init) 1 -3.33 [-3.33, -3.33] yes
Persistence (baseline) 28 +3.51 [2.77, 4.24] yes

Cite this page

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

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