Raw model output on the native 0.25° grid — no MOS, no bias correction, no post-processing. Scores understate operational forecast quality. Read the fairness statement →

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

Minneapolis-St Paul · NCEP GFS · lead day 6

KMSP · gfs · lead 6

Target day = initialization date + 6 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, gfs-0p25, 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
tmax00Zbilinear30d24 1 QC4.75 [2.99, 6.74]4.80-1.20 [-4.31, 1.87]6.23 [4.02, 8.16]17% [3%, 36%]21%46%-0.37-0.392026-08-07 → 2026-08-30
tmax00Zbilinear90d24 1 QC4.75 [2.81, 7.19]4.80-1.20 [-4.52, 2.42]6.23 [3.93, 8.34]17% [0%, 39%]21%46%-0.37-0.392026-08-07 → 2026-08-30
tmax00Zbilinear365d24 1 QC4.75 [2.75, 7.13]4.80-1.20 [-4.74, 2.65]6.23 [3.69, 8.33]17% [0%, 43%]21%46%-0.37-0.392026-08-07 → 2026-08-30
tmax00Zbilinearall24 1 QC4.75 [2.75, 7.15]4.80-1.20 [-4.61, 2.79]6.23 [3.77, 8.31]17% [0%, 41%]21%46%-0.37-0.392026-08-07 → 2026-08-30
tmax00Znearest30d24 1 QC4.38 [2.91, 6.10]4.39-0.70 [-3.46, 1.99]5.75 [3.97, 7.42]25% [6%, 46%]33%38%-0.27-0.272026-08-07 → 2026-08-30
tmax00Znearest90d24 1 QC4.38 [2.75, 6.71]4.39-0.70 [-3.58, 2.48]5.75 [3.76, 7.66]25% [0%, 47%]33%38%-0.27-0.272026-08-07 → 2026-08-30
tmax00Znearest365d24 1 QC4.38 [2.64, 6.61]4.39-0.70 [-3.76, 2.62]5.75 [3.45, 7.59]25% [0%, 50%]33%38%-0.27-0.272026-08-07 → 2026-08-30
tmax00Znearestall24 1 QC4.38 [2.72, 6.68]4.39-0.70 [-3.76, 2.67]5.75 [3.54, 7.65]25% [0%, 50%]33%38%-0.27-0.272026-08-07 → 2026-08-30
tmax12Zbilinear30d24 1 QC4.60 [3.65, 5.55]4.58+0.09 [-2.88, 3.01]6.00 [4.53, 7.28]17% [6%, 27%]33%33%-0.33-0.322026-08-07 → 2026-08-30
tmax12Zbilinear90d24 1 QC4.60 [3.49, 5.60]4.58+0.09 [-2.93, 3.34]6.00 [4.22, 7.28]17% [6%, 29%]33%33%-0.33-0.322026-08-07 → 2026-08-30
tmax12Zbilinear365d24 1 QC4.60 [3.36, 5.63]4.58+0.09 [-3.28, 3.55]6.00 [4.09, 7.26]17% [4%, 29%]33%33%-0.33-0.322026-08-07 → 2026-08-30
tmax12Zbilinearall24 1 QC4.60 [3.38, 5.63]4.58+0.09 [-3.18, 3.55]6.00 [4.14, 7.34]17% [0%, 29%]33%33%-0.33-0.322026-08-07 → 2026-08-30
tmax12Znearest30d24 1 QC4.53 [3.42, 5.55]4.51+0.40 [-2.52, 3.12]6.01 [4.52, 7.32]12% [3%, 26%]33%42%-0.31-0.302026-08-07 → 2026-08-30
tmax12Znearest90d24 1 QC4.53 [3.11, 5.60]4.51+0.40 [-2.53, 3.58]6.01 [4.19, 7.46]12% [0%, 27%]33%42%-0.31-0.302026-08-07 → 2026-08-30
tmax12Znearest365d24 1 QC4.53 [3.11, 5.55]4.51+0.40 [-3.03, 3.60]6.01 [3.95, 7.39]12% [0%, 29%]33%42%-0.31-0.302026-08-07 → 2026-08-30
tmax12Znearestall24 1 QC4.53 [3.10, 5.67]4.51+0.40 [-2.74, 3.70]6.01 [4.00, 7.50]12% [0%, 33%]33%42%-0.31-0.302026-08-07 → 2026-08-30
tmin00Zbilinear30d24 1 QC4.46 [2.94, 6.43]4.50-2.13 [-5.42, 1.10]5.60 [3.63, 7.34]17% [0%, 36%]29%50%+0.24+0.242026-08-07 → 2026-08-30
tmin00Zbilinear90d24 1 QC4.46 [2.77, 6.46]4.50-2.13 [-5.74, 1.46]5.60 [3.28, 7.44]17% [0%, 39%]29%50%+0.24+0.242026-08-07 → 2026-08-30
tmin00Zbilinear365d24 1 QC4.46 [2.72, 6.76]4.50-2.13 [-6.26, 1.61]5.60 [3.16, 7.60]17% [0%, 40%]29%50%+0.24+0.242026-08-07 → 2026-08-30
tmin00Zbilinearall24 1 QC4.46 [2.73, 6.68]4.50-2.13 [-6.11, 1.62]5.60 [3.15, 7.59]17% [0%, 38%]29%50%+0.24+0.242026-08-07 → 2026-08-30
tmin00Znearest30d24 1 QC4.26 [3.10, 5.71]4.33-1.09 [-4.42, 2.27]5.28 [4.02, 6.60]21% [9%, 33%]33%42%+0.28+0.272026-08-07 → 2026-08-30
tmin00Znearest90d24 1 QC4.26 [3.01, 5.75]4.33-1.09 [-4.75, 2.58]5.28 [3.95, 6.63]21% [8%, 35%]33%42%+0.28+0.272026-08-07 → 2026-08-30
tmin00Znearest365d24 1 QC4.26 [2.96, 5.86]4.33-1.09 [-5.21, 2.77]5.28 [3.83, 6.69]21% [8%, 37%]33%42%+0.28+0.272026-08-07 → 2026-08-30
tmin00Znearestall24 1 QC4.26 [2.90, 5.82]4.33-1.09 [-5.09, 2.75]5.28 [3.85, 6.69]21% [8%, 36%]33%42%+0.28+0.272026-08-07 → 2026-08-30
tmin12Zbilinear30d24 1 QC4.74 [3.68, 5.63]4.53-1.27 [-3.43, 0.91]5.44 [4.19, 6.24]0% [0%, 0%]12%38%+0.19+0.232026-08-07 → 2026-08-30
tmin12Zbilinear90d24 1 QC4.74 [3.28, 5.66]4.53-1.27 [-3.67, 1.25]5.44 [3.56, 6.26]0% [0%, 0%]12%38%+0.19+0.232026-08-07 → 2026-08-30
tmin12Zbilinear365d24 1 QC4.74 [3.23, 5.71]4.53-1.27 [-4.08, 1.38]5.44 [3.62, 6.33]0% [0%, 0%]12%38%+0.19+0.232026-08-07 → 2026-08-30
tmin12Zbilinearall24 1 QC4.74 [3.23, 5.76]4.53-1.27 [-3.81, 1.28]5.44 [3.61, 6.38]0% [0%, 0%]12%38%+0.19+0.232026-08-07 → 2026-08-30
tmin12Znearest30d24 1 QC4.47 [3.05, 5.57]4.44-0.16 [-2.48, 2.19]5.30 [3.91, 6.28]12% [0%, 30%]21%33%+0.24+0.252026-08-07 → 2026-08-30
tmin12Znearest90d24 1 QC4.47 [2.44, 5.67]4.44-0.16 [-2.69, 2.32]5.30 [3.23, 6.41]12% [0%, 33%]21%33%+0.24+0.252026-08-07 → 2026-08-30
tmin12Znearest365d24 1 QC4.47 [2.40, 5.76]4.44-0.16 [-3.14, 2.57]5.30 [3.25, 6.44]12% [0%, 33%]21%33%+0.24+0.252026-08-07 → 2026-08-30
tmin12Znearestall24 1 QC4.47 [2.14, 5.72]4.44-0.16 [-2.93, 2.49]5.30 [3.25, 6.43]12% [0%, 37%]21%33%+0.24+0.252026-08-07 → 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 NCEP GFS at KMSP, lead day 6, 00Z bilinear tmax+20+100-10-202026-08-07: +9.28 °F2026-08-08: +5.98 °F2026-08-09: -2.92 °F2026-08-10: -12.69 °F2026-08-11: -7.54 °F2026-08-12: -4.33 °F2026-08-13: +2.22 °F2026-08-14: -6.84 °F2026-08-15: -16.85 °F2026-08-16: -4.79 °F2026-08-17: -2.06 °F2026-08-18: +2.06 °F2026-08-19: -0.43 °F2026-08-20: +5.29 °F2026-08-21: +3.63 °F2026-08-22: +4.18 °F2026-08-23: -2.78 °F2026-08-24: +7.58 °F2026-08-25: +2 °F2026-08-26: -0.16 °F2026-08-27: +0.33 °F2026-08-28: -1.89 °F2026-08-29: -8.15 °F2026-08-30: -0.02 °F2026-08-072026-08-30°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 (24 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-0.02
2026-08-29-8.15
2026-08-28-1.89
2026-08-27+0.33
2026-08-26-0.16
2026-08-25+2.00
2026-08-24+7.58
2026-08-23-2.78
2026-08-22+4.18
2026-08-21+3.63
2026-08-20+5.29
2026-08-19-0.43
2026-08-18+2.06
2026-08-17-2.06
2026-08-16-4.79
2026-08-15-16.85
2026-08-14-6.84
2026-08-13+2.22
2026-08-12-4.33
2026-08-11-7.54
2026-08-10-12.69
2026-08-09-2.92
2026-08-08+5.98
2026-08-07+9.28

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KMSP, lead day 6-20 to -18 °F: 0 days-18 to -16 °F: 1 day-16 to -14 °F: 0 days-14 to -12 °F: 1 day-12 to -10 °F: 0 days-10 to -8 °F: 1 day-8 to -6 °F: 2 days-6 to -4 °F: 2 days-4 to -2 °F: 3 days-2 to 0 °F: 4 days0 to 2 °F: 1 day2 to 4 °F: 4 days4 to 6 °F: 3 days6 to 8 °F: 1 day8 to 10 °F: 1 day10 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| 3.91 · P90 |e| 8.94 °F-200+20 °Fn = 24 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
-18.00-16.001
-16.00-14.000
-14.00-12.001
-12.00-10.000
-10.00-8.001
-8.00-6.002
-6.00-4.002
-4.00-2.003
-2.00+0.004
+0.00+2.001
+2.00+4.004
+4.00+6.003
+6.00+8.001
+8.00+10.001
+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
2026-08244.75 -1.20

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-07 → 2026-08-30 24
NCEP GFS2026-08-07 → 2026-08-30 24
NCEP GFS2026-08-07 → 2026-08-30 24
NCEP GFS2026-08-07 → 2026-08-30 24

Compared with other models

Paired bootstrap on the days both models cover (90d, 00Z, bilinear, daily maximum). Negative means NCEP GFS has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 24 -1.10 [-3.38, 2.15] no
GraphCast (IFS init) 24 -2.17 [-4.32, 0.58] no
ECMWF IFS HRES 19 -0.71 [-2.38, 2.96] no
Persistence (baseline) 24 +1.29 [0.36, 2.47] yes

Cite this page

ShortCastCheck, KMSP gfs lead 6, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KMSP/model/gfs/lead/6/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KMSP (Minneapolis-St Paul), model gfs, lead day 6. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KMSP/model/gfs/lead/6/

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