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

Minneapolis-St Paul · ECMWF AIFS Single · lead day 9

KMSP · 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 QC6.04 [3.59, 9.32]4.06-5.49 [-9.31, -2.50]7.33 [4.48, 10.08]10% [0%, 22%]24%29%-1.19-0.472026-08-10 → 2026-08-30
tmax00Zbilinear90d21 1 QC6.04 [3.58, 10.09]4.06-5.49 [-10.09, -2.55]7.33 [4.39, 10.74]10% [0%, 24%]24%29%-1.19-0.472026-08-10 → 2026-08-30
tmax00Zbilinear365d21 1 QC6.04 [3.41, 10.07]4.06-5.49 [-10.07, -2.19]7.33 [4.27, 10.70]10% [0%, 25%]24%29%-1.19-0.472026-08-10 → 2026-08-30
tmax00Zbilinearall21 1 QC6.04 [3.32, 10.09]4.06-5.49 [-10.09, -2.21]7.33 [4.24, 10.70]10% [0%, 23%]24%29%-1.19-0.472026-08-10 → 2026-08-30
tmax00Znearest30d21 1 QC6.02 [3.60, 9.19]4.03-5.49 [-9.19, -2.56]7.29 [4.57, 9.94]14% [0%, 30%]24%29%-1.18-0.462026-08-10 → 2026-08-30
tmax00Znearest90d21 1 QC6.02 [3.59, 10.01]4.03-5.49 [-10.01, -2.63]7.29 [4.50, 10.59]14% [0%, 32%]24%29%-1.18-0.462026-08-10 → 2026-08-30
tmax00Znearest365d21 1 QC6.02 [3.40, 9.98]4.03-5.49 [-9.98, -2.24]7.29 [4.35, 10.58]14% [0%, 30%]24%29%-1.18-0.462026-08-10 → 2026-08-30
tmax00Znearestall21 1 QC6.02 [3.33, 9.91]4.03-5.49 [-9.91, -2.25]7.29 [4.31, 10.56]14% [0%, 33%]24%29%-1.18-0.462026-08-10 → 2026-08-30
tmax12Zbilinear30d21 1 QC6.84 [5.20, 8.78]4.79-5.98 [-8.74, -3.49]8.35 [6.85, 9.58]10% [0%, 25%]24%29%-1.48-0.732026-08-10 → 2026-08-30
tmax12Zbilinear90d21 1 QC6.84 [5.09, 9.26]4.79-5.98 [-9.26, -3.10]8.35 [6.63, 10.08]10% [0%, 26%]24%29%-1.48-0.732026-08-10 → 2026-08-30
tmax12Zbilinear365d21 1 QC6.84 [5.20, 9.12]4.79-5.98 [-9.12, -3.10]8.35 [6.96, 9.95]10% [0%, 29%]24%29%-1.48-0.732026-08-10 → 2026-08-30
tmax12Zbilinearall21 1 QC6.84 [5.13, 9.02]4.79-5.98 [-8.99, -3.07]8.35 [6.92, 9.94]10% [0%, 25%]24%29%-1.48-0.732026-08-10 → 2026-08-30
tmax12Znearest30d21 1 QC6.81 [5.20, 8.69]4.75-5.94 [-8.68, -3.52]8.31 [6.83, 9.52]5% [0%, 13%]24%29%-1.47-0.722026-08-10 → 2026-08-30
tmax12Znearest90d21 1 QC6.81 [5.12, 9.17]4.75-5.94 [-9.17, -3.11]8.31 [6.68, 10.05]5% [0%, 13%]24%29%-1.47-0.722026-08-10 → 2026-08-30
tmax12Znearest365d21 1 QC6.81 [5.21, 9.08]4.75-5.94 [-9.08, -3.12]8.31 [6.94, 9.87]5% [0%, 14%]24%29%-1.47-0.722026-08-10 → 2026-08-30
tmax12Znearestall21 1 QC6.81 [5.16, 9.06]4.75-5.94 [-9.06, -3.06]8.31 [6.98, 9.88]5% [0%, 14%]24%29%-1.47-0.722026-08-10 → 2026-08-30
tmin00Zbilinear30d21 1 QC5.58 [3.23, 7.65]5.52-1.33 [-6.57, 2.92]7.32 [4.70, 8.97]24% [8%, 40%]38%43%-0.07-0.042026-08-10 → 2026-08-30
tmin00Zbilinear90d21 1 QC5.58 [2.60, 7.93]5.52-1.33 [-7.67, 2.88]7.32 [3.88, 9.15]24% [0%, 40%]38%43%-0.07-0.042026-08-10 → 2026-08-30
tmin00Zbilinear365d21 1 QC5.58 [2.62, 7.74]5.52-1.33 [-7.61, 3.15]7.32 [3.85, 9.15]24% [0%, 42%]38%43%-0.07-0.042026-08-10 → 2026-08-30
tmin00Zbilinearall21 1 QC5.58 [2.57, 7.93]5.52-1.33 [-7.91, 3.19]7.32 [3.75, 9.11]24% [0%, 41%]38%43%-0.07-0.042026-08-10 → 2026-08-30
tmin00Znearest30d21 1 QC5.66 [3.26, 7.82]5.52-1.51 [-6.77, 2.77]7.37 [4.71, 9.11]24% [8%, 40%]38%38%-0.09-0.042026-08-10 → 2026-08-30
tmin00Znearest90d21 1 QC5.66 [2.62, 8.07]5.52-1.51 [-7.88, 2.74]7.37 [3.86, 9.31]24% [0%, 40%]38%38%-0.09-0.042026-08-10 → 2026-08-30
tmin00Znearest365d21 1 QC5.66 [2.65, 7.89]5.52-1.51 [-7.82, 3.02]7.37 [3.80, 9.31]24% [0%, 42%]38%38%-0.09-0.042026-08-10 → 2026-08-30
tmin00Znearestall21 1 QC5.66 [2.55, 8.12]5.52-1.51 [-8.12, 3.06]7.37 [3.74, 9.27]24% [0%, 41%]38%38%-0.09-0.042026-08-10 → 2026-08-30
tmin12Zbilinear30d21 1 QC5.70 [3.92, 8.18]4.52-3.20 [-7.73, 0.23]6.77 [4.70, 8.85]5% [0%, 13%]10%33%-0.10+0.152026-08-10 → 2026-08-30
tmin12Zbilinear90d21 1 QC5.70 [3.82, 8.98]4.52-3.20 [-8.98, 0.36]6.77 [4.25, 9.45]5% [0%, 13%]10%33%-0.10+0.152026-08-10 → 2026-08-30
tmin12Zbilinear365d21 1 QC5.70 [3.67, 8.98]4.52-3.20 [-8.95, 0.63]6.77 [4.05, 9.46]5% [0%, 14%]10%33%-0.10+0.152026-08-10 → 2026-08-30
tmin12Zbilinearall21 1 QC5.70 [3.64, 8.84]4.52-3.20 [-8.84, 0.56]6.77 [4.14, 9.35]5% [0%, 14%]10%33%-0.10+0.152026-08-10 → 2026-08-30
tmin12Znearest30d21 1 QC5.73 [3.96, 8.29]4.49-3.35 [-7.83, 0.06]6.81 [4.74, 8.95]5% [0%, 13%]10%33%-0.10+0.162026-08-10 → 2026-08-30
tmin12Znearest90d21 1 QC5.73 [3.88, 9.09]4.49-3.35 [-9.09, 0.18]6.81 [4.32, 9.58]5% [0%, 13%]10%33%-0.10+0.162026-08-10 → 2026-08-30
tmin12Znearest365d21 1 QC5.73 [3.75, 9.09]4.49-3.35 [-9.07, 0.45]6.81 [4.13, 9.58]5% [0%, 14%]10%33%-0.10+0.162026-08-10 → 2026-08-30
tmin12Znearestall21 1 QC5.73 [3.71, 8.97]4.49-3.35 [-8.97, 0.37]6.81 [4.22, 9.48]5% [0%, 14%]10%33%-0.10+0.162026-08-10 → 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 KMSP, lead day 9, 00Z bilinear tmax+20+100-10-202026-08-10: -13.54 °F2026-08-11: -9.78 °F2026-08-12: -12.89 °F2026-08-13: -3.6 °F2026-08-14: -9.33 °F2026-08-15: -14.09 °F2026-08-16: -7.01 °F2026-08-17: -8.74 °F2026-08-18: -3.87 °F2026-08-19: -0.85 °F2026-08-20: +1.14 °F2026-08-21: -9.11 °F2026-08-22: -0.44 °F2026-08-23: +2.6 °F2026-08-24: -1.13 °F2026-08-25: -4.35 °F2026-08-26: +1.99 °F2026-08-27: -5.13 °F2026-08-28: -6.59 °F2026-08-29: -6.48 °F2026-08-30: -4.14 °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
2026-08-30-4.14
2026-08-29-6.48
2026-08-28-6.59
2026-08-27-5.13
2026-08-26+1.99
2026-08-25-4.35
2026-08-24-1.13
2026-08-23+2.60
2026-08-22-0.44
2026-08-21-9.11
2026-08-20+1.14
2026-08-19-0.85
2026-08-18-3.87
2026-08-17-8.74
2026-08-16-7.01
2026-08-15-14.09
2026-08-14-9.33
2026-08-13-3.60
2026-08-12-12.89
2026-08-11-9.78
2026-08-10-13.54

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KMSP, lead day 9-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 1 day-14 to -12 °F: 2 days-12 to -10 °F: 0 days-10 to -8 °F: 4 days-8 to -6 °F: 3 days-6 to -4 °F: 3 days-4 to -2 °F: 2 days-2 to 0 °F: 3 days0 to 2 °F: 2 days2 to 4 °F: 1 day4 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| 5.13 · P90 |e| 12.89 °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
-16.00-14.001
-14.00-12.002
-12.00-10.000
-10.00-8.004
-8.00-6.003
-6.00-4.003
-4.00-2.002
-2.00+0.003
+0.00+2.002
+2.00+4.001
+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
2026-08216.04 -5.49

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 -0.35 [-2.30, 2.57] no
GraphCast (IFS init) 21 -0.40 [-2.45, 1.04] no
ECMWF IFS HRES 16 -0.82 [-2.41, 5.77] no
Persistence (baseline) 21 +3.28 [0.28, 8.06] yes

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KMSP (Minneapolis-St Paul), 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/KMSP/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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