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

New Orleans Intl · NCEP GFS · lead day 6

KMSY · 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 QC4.53 [3.92, 5.16]2.47-4.46 [-5.13, -3.78]5.36 [4.78, 6.06]8% [0%, 20%]25%33%-0.58+0.142026-08-07 → 2026-08-30
tmax00Zbilinear90d24 1 QC4.53 [3.89, 5.35]2.47-4.46 [-5.29, -3.80]5.36 [4.79, 6.32]8% [0%, 23%]25%33%-0.58+0.142026-08-07 → 2026-08-30
tmax00Zbilinear365d24 1 QC4.53 [3.86, 5.25]2.47-4.46 [-5.18, -3.70]5.36 [4.77, 6.11]8% [0%, 22%]25%33%-0.58+0.142026-08-07 → 2026-08-30
tmax00Zbilinearall24 1 QC4.53 [3.89, 5.40]2.47-4.46 [-5.32, -3.74]5.36 [4.78, 6.35]8% [0%, 25%]25%33%-0.58+0.142026-08-07 → 2026-08-30
tmax00Znearest30d24 1 QC4.61 [4.02, 5.24]2.43-4.55 [-5.22, -3.88]5.41 [4.85, 6.10]8% [0%, 20%]25%33%-0.60+0.162026-08-07 → 2026-08-30
tmax00Znearest90d24 1 QC4.61 [3.99, 5.43]2.43-4.55 [-5.36, -3.90]5.41 [4.85, 6.36]8% [0%, 23%]25%33%-0.60+0.162026-08-07 → 2026-08-30
tmax00Znearest365d24 1 QC4.61 [3.95, 5.28]2.43-4.55 [-5.26, -3.84]5.41 [4.84, 6.15]8% [0%, 22%]25%33%-0.60+0.162026-08-07 → 2026-08-30
tmax00Znearestall24 1 QC4.61 [3.96, 5.46]2.43-4.55 [-5.42, -3.86]5.41 [4.84, 6.39]8% [0%, 25%]25%33%-0.60+0.162026-08-07 → 2026-08-30
tmax12Zbilinear30d24 1 QC4.90 [3.72, 6.26]2.51-4.65 [-5.85, -3.62]5.66 [4.17, 6.99]4% [0%, 11%]8%29%-0.70+0.132026-08-07 → 2026-08-30
tmax12Zbilinear90d24 1 QC4.90 [3.54, 6.53]2.51-4.65 [-6.05, -3.51]5.66 [3.97, 7.25]4% [0%, 12%]8%29%-0.70+0.132026-08-07 → 2026-08-30
tmax12Zbilinear365d24 1 QC4.90 [3.54, 6.61]2.51-4.65 [-6.08, -3.49]5.66 [3.88, 7.33]4% [0%, 13%]8%29%-0.70+0.132026-08-07 → 2026-08-30
tmax12Zbilinearall24 1 QC4.90 [3.58, 6.60]2.51-4.65 [-6.08, -3.55]5.66 [3.98, 7.28]4% [0%, 13%]8%29%-0.70+0.132026-08-07 → 2026-08-30
tmax12Znearest30d24 1 QC4.97 [3.80, 6.30]2.50-4.74 [-5.91, -3.72]5.72 [4.26, 7.02]4% [0%, 11%]8%29%-0.73+0.132026-08-07 → 2026-08-30
tmax12Znearest90d24 1 QC4.97 [3.62, 6.58]2.50-4.74 [-6.11, -3.61]5.72 [4.08, 7.27]4% [0%, 12%]8%29%-0.73+0.132026-08-07 → 2026-08-30
tmax12Znearest365d24 1 QC4.97 [3.62, 6.65]2.50-4.74 [-6.15, -3.61]5.72 [3.95, 7.35]4% [0%, 13%]8%29%-0.73+0.132026-08-07 → 2026-08-30
tmax12Znearestall24 1 QC4.97 [3.64, 6.63]2.50-4.74 [-6.16, -3.64]5.72 [4.07, 7.33]4% [0%, 13%]8%29%-0.73+0.132026-08-07 → 2026-08-30
tmin00Zbilinear30d24 1 QC2.27 [1.47, 3.18]2.06+0.99 [-0.06, 2.00]2.80 [1.83, 3.67]25% [7%, 41%]54%67%-0.09+0.012026-08-07 → 2026-08-30
tmin00Zbilinear90d24 1 QC2.27 [1.48, 3.31]2.06+0.99 [-0.07, 2.09]2.80 [1.76, 3.74]25% [0%, 40%]54%67%-0.09+0.012026-08-07 → 2026-08-30
tmin00Zbilinear365d24 1 QC2.27 [1.39, 3.33]2.06+0.99 [-0.28, 2.16]2.80 [1.65, 3.78]25% [0%, 43%]54%67%-0.09+0.012026-08-07 → 2026-08-30
tmin00Zbilinearall24 1 QC2.27 [1.45, 3.39]2.06+0.99 [-0.28, 2.08]2.80 [1.70, 3.83]25% [0%, 43%]54%67%-0.09+0.012026-08-07 → 2026-08-30
tmin00Znearest30d24 1 QC2.27 [1.47, 3.20]2.06+1.02 [-0.03, 2.04]2.81 [1.84, 3.68]25% [7%, 41%]54%67%-0.09+0.012026-08-07 → 2026-08-30
tmin00Znearest90d24 1 QC2.27 [1.48, 3.33]2.06+1.02 [-0.04, 2.12]2.81 [1.76, 3.76]25% [0%, 40%]54%67%-0.09+0.012026-08-07 → 2026-08-30
tmin00Znearest365d24 1 QC2.27 [1.39, 3.36]2.06+1.02 [-0.23, 2.20]2.81 [1.64, 3.79]25% [0%, 43%]54%67%-0.09+0.012026-08-07 → 2026-08-30
tmin00Znearestall24 1 QC2.27 [1.45, 3.41]2.06+1.02 [-0.23, 2.12]2.81 [1.71, 3.84]25% [0%, 43%]54%67%-0.09+0.012026-08-07 → 2026-08-30
tmin12Zbilinear30d24 1 QC2.19 [1.33, 3.13]1.88+1.18 [0.13, 2.19]2.73 [1.73, 3.56]29% [10%, 50%]54%71%-0.05+0.102026-08-07 → 2026-08-30
tmin12Zbilinear90d24 1 QC2.19 [1.32, 3.27]1.88+1.18 [-0.03, 2.49]2.73 [1.74, 3.70]29% [6%, 52%]54%71%-0.05+0.102026-08-07 → 2026-08-30
tmin12Zbilinear365d24 1 QC2.19 [1.20, 3.31]1.88+1.18 [-0.13, 2.53]2.73 [1.57, 3.73]29% [5%, 57%]54%71%-0.05+0.102026-08-07 → 2026-08-30
tmin12Zbilinearall24 1 QC2.19 [1.23, 3.36]1.88+1.18 [-0.22, 2.50]2.73 [1.57, 3.77]29% [0%, 54%]54%71%-0.05+0.102026-08-07 → 2026-08-30
tmin12Znearest30d24 1 QC2.21 [1.34, 3.16]1.88+1.23 [0.17, 2.24]2.74 [1.75, 3.56]25% [0%, 50%]54%71%-0.06+0.102026-08-07 → 2026-08-30
tmin12Znearest90d24 1 QC2.21 [1.33, 3.28]1.88+1.23 [0.01, 2.55]2.74 [1.76, 3.70]25% [0%, 50%]54%71%-0.06+0.102026-08-07 → 2026-08-30
tmin12Znearest365d24 1 QC2.21 [1.19, 3.33]1.88+1.23 [-0.09, 2.60]2.74 [1.56, 3.74]25% [0%, 57%]54%71%-0.06+0.102026-08-07 → 2026-08-30
tmin12Znearestall24 1 QC2.21 [1.24, 3.37]1.88+1.23 [-0.16, 2.56]2.74 [1.60, 3.77]25% [0%, 50%]54%71%-0.06+0.102026-08-07 → 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 KMSY, lead day 6, 00Z bilinear tmax+10+50-5-102026-08-07: -9.22 °F2026-08-08: -2.42 °F2026-08-09: -1.59 °F2026-08-10: -9.37 °F2026-08-11: -1.19 °F2026-08-12: +0.31 °F2026-08-13: -4.52 °F2026-08-14: -3.56 °F2026-08-15: -5.92 °F2026-08-16: -7.71 °F2026-08-17: -5.54 °F2026-08-18: -1.71 °F2026-08-19: -3.29 °F2026-08-20: -2.71 °F2026-08-21: -3.81 °F2026-08-22: -7.07 °F2026-08-23: -9.46 °F2026-08-24: -4.06 °F2026-08-25: -4.72 °F2026-08-26: -3.51 °F2026-08-27: -1.35 °F2026-08-28: -6.27 °F2026-08-29: -8.95 °F2026-08-30: +0.55 °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+0.55
2026-08-29-8.95
2026-08-28-6.27
2026-08-27-1.35
2026-08-26-3.51
2026-08-25-4.72
2026-08-24-4.06
2026-08-23-9.46
2026-08-22-7.07
2026-08-21-3.81
2026-08-20-2.71
2026-08-19-3.29
2026-08-18-1.71
2026-08-17-5.54
2026-08-16-7.71
2026-08-15-5.92
2026-08-14-3.56
2026-08-13-4.52
2026-08-12+0.31
2026-08-11-1.19
2026-08-10-9.37
2026-08-09-1.59
2026-08-08-2.42
2026-08-07-9.22

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KMSY, lead day 6-10 to -9 °F: 3 days-9 to -8 °F: 1 day-8 to -7 °F: 2 days-7 to -6 °F: 1 day-6 to -5 °F: 2 days-5 to -4 °F: 3 days-4 to -3 °F: 4 days-3 to -2 °F: 2 days-2 to -1 °F: 4 days-1 to 0 °F: 0 days0 to 1 °F: 2 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| 3.93 · P90 |e| 9.14 °F-100+10 °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
-10.00-9.003
-9.00-8.001
-8.00-7.002
-7.00-6.001
-6.00-5.002
-5.00-4.003
-4.00-3.004
-3.00-2.002
-2.00-1.004
-1.00+0.000
+0.00+1.002
+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
2026-08244.53 -4.46

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 -0.46 [-1.78, 0.57] no
GraphCast (IFS init) 24 -1.07 [-2.00, -0.11] yes
ECMWF IFS HRES 19 +0.30 [-1.07, 3.41] no
Persistence (baseline) 24 +1.66 [0.16, 3.11] yes

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KMSY (New Orleans Intl), 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/KMSY/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