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

Newark Liberty · ECMWF AIFS Single · lead day 9

KEWR · 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 QC5.51 [3.95, 7.28]3.45-4.99 [-7.22, -2.86]6.51 [4.77, 7.95]14% [0%, 30%]24%33%-0.34-0.022026-08-10 → 2026-08-30
tmax00Zbilinear90d21 1 QC5.51 [3.76, 7.36]3.45-4.99 [-7.33, -2.54]6.51 [4.44, 7.99]14% [0%, 33%]24%33%-0.34-0.022026-08-10 → 2026-08-30
tmax00Zbilinear365d21 1 QC5.51 [3.72, 7.50]3.45-4.99 [-7.48, -2.40]6.51 [4.33, 8.18]14% [0%, 33%]24%33%-0.34-0.022026-08-10 → 2026-08-30
tmax00Zbilinearall21 1 QC5.51 [3.68, 7.59]3.45-4.99 [-7.54, -2.34]6.51 [4.33, 8.27]14% [0%, 33%]24%33%-0.34-0.022026-08-10 → 2026-08-30
tmax00Znearest30d21 1 QC5.75 [4.11, 7.61]3.64-5.18 [-7.52, -2.96]6.80 [5.00, 8.33]14% [0%, 30%]24%29%-0.40-0.072026-08-10 → 2026-08-30
tmax00Znearest90d21 1 QC5.75 [3.99, 7.68]3.64-5.18 [-7.63, -2.58]6.80 [4.75, 8.36]14% [0%, 33%]24%29%-0.40-0.072026-08-10 → 2026-08-30
tmax00Znearest365d21 1 QC5.75 [3.95, 7.82]3.64-5.18 [-7.82, -2.49]6.80 [4.65, 8.57]14% [0%, 33%]24%29%-0.40-0.072026-08-10 → 2026-08-30
tmax00Znearestall21 1 QC5.75 [3.87, 7.94]3.64-5.18 [-7.86, -2.44]6.80 [4.64, 8.67]14% [0%, 33%]24%29%-0.40-0.072026-08-10 → 2026-08-30
tmax12Zbilinear30d21 1 QC4.99 [3.50, 6.84]2.72-4.92 [-6.84, -3.35]5.99 [4.29, 7.60]10% [0%, 22%]14%33%-0.22+0.202026-08-10 → 2026-08-30
tmax12Zbilinear90d21 1 QC4.99 [3.18, 7.30]2.72-4.92 [-7.30, -3.07]5.99 [3.75, 7.94]10% [0%, 22%]14%33%-0.22+0.202026-08-10 → 2026-08-30
tmax12Zbilinear365d21 1 QC4.99 [3.14, 7.22]2.72-4.92 [-7.22, -3.07]5.99 [3.71, 7.91]10% [0%, 25%]14%33%-0.22+0.202026-08-10 → 2026-08-30
tmax12Zbilinearall21 1 QC4.99 [3.41, 7.46]2.72-4.92 [-7.46, -3.19]5.99 [4.12, 8.01]10% [0%, 21%]14%33%-0.22+0.202026-08-10 → 2026-08-30
tmax12Znearest30d21 1 QC5.15 [3.63, 6.99]2.79-5.06 [-6.99, -3.45]6.17 [4.43, 7.77]10% [0%, 25%]14%29%-0.26+0.172026-08-10 → 2026-08-30
tmax12Znearest90d21 1 QC5.15 [3.30, 7.46]2.79-5.06 [-7.46, -3.11]6.17 [3.88, 8.13]10% [0%, 26%]14%29%-0.26+0.172026-08-10 → 2026-08-30
tmax12Znearest365d21 1 QC5.15 [3.27, 7.41]2.79-5.06 [-7.41, -3.11]6.17 [3.84, 8.10]10% [0%, 29%]14%29%-0.26+0.172026-08-10 → 2026-08-30
tmax12Znearestall21 1 QC5.15 [3.51, 7.61]2.79-5.06 [-7.61, -3.26]6.17 [4.28, 8.16]10% [0%, 25%]14%29%-0.26+0.172026-08-10 → 2026-08-30
tmin00Zbilinear30d21 1 QC3.96 [3.04, 4.97]3.82+1.19 [-0.43, 2.91]4.61 [3.43, 5.72]10% [0%, 23%]19%33%-0.01-0.182026-08-10 → 2026-08-30
tmin00Zbilinear90d21 1 QC3.96 [2.98, 5.06]3.82+1.19 [-0.41, 3.27]4.61 [3.37, 5.78]10% [0%, 23%]19%33%-0.01-0.182026-08-10 → 2026-08-30
tmin00Zbilinear365d21 1 QC3.96 [2.96, 5.10]3.82+1.19 [-0.54, 3.29]4.61 [3.34, 5.90]10% [0%, 25%]19%33%-0.01-0.182026-08-10 → 2026-08-30
tmin00Zbilinearall21 1 QC3.96 [2.87, 5.30]3.82+1.19 [-0.67, 3.23]4.61 [3.30, 5.93]10% [0%, 25%]19%33%-0.01-0.182026-08-10 → 2026-08-30
tmin00Znearest30d21 1 QC3.98 [2.95, 4.94]3.97+0.25 [-1.36, 1.96]4.62 [3.55, 5.53]10% [0%, 25%]29%33%-0.02-0.222026-08-10 → 2026-08-30
tmin00Znearest90d21 1 QC3.98 [2.91, 5.01]3.97+0.25 [-1.38, 2.34]4.62 [3.49, 5.54]10% [0%, 30%]29%33%-0.02-0.222026-08-10 → 2026-08-30
tmin00Znearest365d21 1 QC3.98 [2.85, 5.10]3.97+0.25 [-1.56, 2.36]4.62 [3.45, 5.62]10% [0%, 29%]29%33%-0.02-0.222026-08-10 → 2026-08-30
tmin00Znearestall21 1 QC3.98 [2.80, 5.16]3.97+0.25 [-1.64, 2.26]4.62 [3.41, 5.70]10% [0%, 29%]29%33%-0.02-0.222026-08-10 → 2026-08-30
tmin12Zbilinear30d21 1 QC3.55 [2.35, 4.59]3.49+1.11 [-1.14, 3.32]4.34 [2.72, 5.58]14% [0%, 25%]33%43%+0.09-0.072026-08-10 → 2026-08-30
tmin12Zbilinear90d21 1 QC3.55 [2.30, 4.67]3.49+1.11 [-1.57, 3.71]4.34 [2.67, 5.68]14% [0%, 25%]33%43%+0.09-0.072026-08-10 → 2026-08-30
tmin12Zbilinear365d21 1 QC3.55 [2.24, 4.73]3.49+1.11 [-1.72, 3.79]4.34 [2.63, 5.72]14% [0%, 29%]33%43%+0.09-0.072026-08-10 → 2026-08-30
tmin12Zbilinearall21 1 QC3.55 [2.32, 4.62]3.49+1.11 [-1.82, 3.25]4.34 [2.71, 5.57]14% [0%, 29%]33%43%+0.09-0.072026-08-10 → 2026-08-30
tmin12Znearest30d21 1 QC3.60 [2.79, 4.43]3.61+0.18 [-2.08, 2.47]4.32 [3.19, 5.24]10% [0%, 18%]29%52%+0.08-0.112026-08-10 → 2026-08-30
tmin12Znearest90d21 1 QC3.60 [2.74, 4.48]3.61+0.18 [-2.58, 2.82]4.32 [3.14, 5.34]10% [0%, 20%]29%52%+0.08-0.112026-08-10 → 2026-08-30
tmin12Znearest365d21 1 QC3.60 [2.72, 4.55]3.61+0.18 [-2.70, 2.92]4.32 [3.09, 5.38]10% [0%, 19%]29%52%+0.08-0.112026-08-10 → 2026-08-30
tmin12Znearestall21 1 QC3.60 [2.77, 4.55]3.61+0.18 [-2.72, 2.39]4.32 [3.22, 5.28]10% [0%, 18%]29%52%+0.08-0.112026-08-10 → 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 KEWR, lead day 9, 00Z bilinear tmax+20+100-10-202026-08-10: -1 °F2026-08-11: -6.98 °F2026-08-12: -7.39 °F2026-08-13: -5.46 °F2026-08-14: -7.6 °F2026-08-15: -8.71 °F2026-08-16: -9.24 °F2026-08-17: -13.48 °F2026-08-18: -6.07 °F2026-08-19: -6.73 °F2026-08-20: -0.51 °F2026-08-21: +2.35 °F2026-08-22: -6.22 °F2026-08-23: -1.98 °F2026-08-24: +2.74 °F2026-08-25: -6.49 °F2026-08-26: -5.77 °F2026-08-27: -0.6 °F2026-08-28: -10.47 °F2026-08-29: +0.34 °F2026-08-30: -5.52 °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
2026-08-30-5.52
2026-08-29+0.34
2026-08-28-10.47
2026-08-27-0.60
2026-08-26-5.77
2026-08-25-6.49
2026-08-24+2.74
2026-08-23-1.98
2026-08-22-6.22
2026-08-21+2.35
2026-08-20-0.51
2026-08-19-6.73
2026-08-18-6.07
2026-08-17-13.48
2026-08-16-9.24
2026-08-15-8.71
2026-08-14-7.60
2026-08-13-5.46
2026-08-12-7.39
2026-08-11-6.98
2026-08-10-1.00

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KEWR, 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: 1 day-12 to -10 °F: 1 day-10 to -8 °F: 2 days-8 to -6 °F: 7 days-6 to -4 °F: 3 days-4 to -2 °F: 0 days-2 to 0 °F: 4 days0 to 2 °F: 1 day2 to 4 °F: 2 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| 6.07 · P90 |e| 9.24 °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
-14.00-12.001
-12.00-10.001
-10.00-8.002
-8.00-6.007
-6.00-4.003
-4.00-2.000
-2.00+0.004
+0.00+2.001
+2.00+4.002
+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
2026-08215.51 -4.99

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 +0.60 [-1.54, 2.97] no
GraphCast (IFS init) 21 +0.04 [-1.24, 1.20] no
ECMWF IFS HRES 16 +0.52 [-6.01, 2.83] no
Persistence (baseline) 21 +1.41 [-0.10, 2.86] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KEWR (Newark Liberty), 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/KEWR/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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