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

Newark Liberty · ECMWF AIFS Single · lead day 8

KEWR · aifs_single · lead 8

Target day = initialization date + 8 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
tmax00Zbilinear30d22 1 QC4.31 [3.27, 5.20]2.11-4.21 [-5.19, -3.08]4.97 [3.84, 5.82]9% [0%, 22%]18%32%+0.01+0.462026-08-09 → 2026-08-30
tmax00Zbilinear90d22 1 QC4.31 [3.24, 5.27]2.11-4.21 [-5.27, -2.99]4.97 [3.69, 5.90]9% [0%, 24%]18%32%+0.01+0.462026-08-09 → 2026-08-30
tmax00Zbilinear365d22 1 QC4.31 [3.10, 5.30]2.11-4.21 [-5.30, -2.91]4.97 [3.59, 5.95]9% [0%, 29%]18%32%+0.01+0.462026-08-09 → 2026-08-30
tmax00Zbilinearall22 1 QC4.31 [3.25, 5.32]2.11-4.21 [-5.32, -3.00]4.97 [3.77, 5.94]9% [0%, 26%]18%32%+0.01+0.462026-08-09 → 2026-08-30
tmax00Znearest30d22 1 QC4.39 [3.28, 5.33]2.16-4.30 [-5.31, -3.12]5.10 [3.90, 6.01]14% [0%, 26%]18%32%-0.01+0.452026-08-09 → 2026-08-30
tmax00Znearest90d22 1 QC4.39 [3.24, 5.39]2.16-4.30 [-5.39, -3.04]5.10 [3.73, 6.06]14% [0%, 27%]18%32%-0.01+0.452026-08-09 → 2026-08-30
tmax00Znearest365d22 1 QC4.39 [3.08, 5.45]2.16-4.30 [-5.45, -2.94]5.10 [3.61, 6.11]14% [0%, 29%]18%32%-0.01+0.452026-08-09 → 2026-08-30
tmax00Znearestall22 1 QC4.39 [3.24, 5.43]2.16-4.30 [-5.43, -3.06]5.10 [3.80, 6.04]14% [0%, 29%]18%32%-0.01+0.452026-08-09 → 2026-08-30
tmax12Zbilinear30d22 1 QC4.19 [3.49, 4.89]1.93-4.04 [-4.85, -3.19]4.71 [4.07, 5.26]18% [5%, 33%]18%27%+0.04+0.512026-08-09 → 2026-08-30
tmax12Zbilinear90d22 1 QC4.19 [3.41, 4.96]1.93-4.04 [-4.95, -3.11]4.71 [3.98, 5.30]18% [0%, 35%]18%27%+0.04+0.512026-08-09 → 2026-08-30
tmax12Zbilinear365d22 1 QC4.19 [3.37, 4.98]1.93-4.04 [-4.98, -3.03]4.71 [3.97, 5.33]18% [0%, 35%]18%27%+0.04+0.512026-08-09 → 2026-08-30
tmax12Zbilinearall22 1 QC4.19 [3.43, 4.99]1.93-4.04 [-4.98, -3.18]4.71 [3.96, 5.32]18% [0%, 33%]18%27%+0.04+0.512026-08-09 → 2026-08-30
tmax12Znearest30d22 1 QC4.31 [3.56, 5.06]2.02-4.16 [-5.03, -3.29]4.88 [4.15, 5.47]9% [0%, 21%]18%27%+0.01+0.492026-08-09 → 2026-08-30
tmax12Znearest90d22 1 QC4.31 [3.47, 5.15]2.02-4.16 [-5.14, -3.18]4.88 [4.08, 5.52]9% [0%, 22%]18%27%+0.01+0.492026-08-09 → 2026-08-30
tmax12Znearest365d22 1 QC4.31 [3.41, 5.16]2.02-4.16 [-5.16, -3.09]4.88 [4.07, 5.55]9% [0%, 23%]18%27%+0.01+0.492026-08-09 → 2026-08-30
tmax12Znearestall22 1 QC4.31 [3.50, 5.15]2.02-4.16 [-5.15, -3.29]4.88 [4.06, 5.54]9% [0%, 23%]18%27%+0.01+0.492026-08-09 → 2026-08-30
tmin00Zbilinear30d22 1 QC2.93 [2.09, 3.61]2.69+1.20 [-0.46, 2.84]3.41 [2.44, 4.04]18% [5%, 36%]32%59%+0.38+0.382026-08-09 → 2026-08-30
tmin00Zbilinear90d22 1 QC2.93 [1.84, 3.69]2.69+1.20 [-0.72, 3.11]3.41 [2.19, 4.13]18% [0%, 40%]32%59%+0.38+0.382026-08-09 → 2026-08-30
tmin00Zbilinear365d22 1 QC2.93 [1.86, 3.77]2.69+1.20 [-0.81, 3.09]3.41 [2.18, 4.17]18% [0%, 40%]32%59%+0.38+0.382026-08-09 → 2026-08-30
tmin00Zbilinearall22 1 QC2.93 [1.79, 3.68]2.69+1.20 [-0.92, 2.85]3.41 [2.16, 4.09]18% [0%, 45%]32%59%+0.38+0.382026-08-09 → 2026-08-30
tmin00Znearest30d22 1 QC2.81 [2.34, 3.25]2.79+0.22 [-1.53, 1.93]3.34 [2.85, 3.69]18% [4%, 30%]41%55%+0.41+0.362026-08-09 → 2026-08-30
tmin00Znearest90d22 1 QC2.81 [2.27, 3.31]2.79+0.22 [-1.79, 2.25]3.34 [2.75, 3.70]18% [0%, 30%]41%55%+0.41+0.362026-08-09 → 2026-08-30
tmin00Znearest365d22 1 QC2.81 [2.26, 3.31]2.79+0.22 [-1.91, 2.24]3.34 [2.81, 3.71]18% [0%, 31%]41%55%+0.41+0.362026-08-09 → 2026-08-30
tmin00Znearestall22 1 QC2.81 [2.26, 3.33]2.79+0.22 [-2.04, 1.96]3.34 [2.67, 3.71]18% [0%, 32%]41%55%+0.41+0.362026-08-09 → 2026-08-30
tmin12Zbilinear30d22 1 QC2.72 [1.67, 3.64]2.37+1.68 [0.57, 2.94]3.38 [2.13, 4.16]23% [0%, 48%]41%64%+0.42+0.462026-08-09 → 2026-08-30
tmin12Zbilinear90d22 1 QC2.72 [1.46, 3.76]2.37+1.68 [0.52, 3.20]3.38 [1.88, 4.18]23% [0%, 50%]41%64%+0.42+0.462026-08-09 → 2026-08-30
tmin12Zbilinear365d22 1 QC2.72 [1.46, 3.81]2.37+1.68 [0.48, 3.29]3.38 [1.80, 4.24]23% [0%, 50%]41%64%+0.42+0.462026-08-09 → 2026-08-30
tmin12Zbilinearall22 1 QC2.72 [1.43, 3.77]2.37+1.68 [0.43, 2.93]3.38 [1.77, 4.11]23% [0%, 50%]41%64%+0.42+0.462026-08-09 → 2026-08-30
tmin12Znearest30d22 1 QC2.53 [1.84, 3.24]2.48+0.74 [-0.44, 2.06]3.12 [2.21, 3.72]23% [7%, 37%]50%64%+0.46+0.432026-08-09 → 2026-08-30
tmin12Znearest90d22 1 QC2.53 [1.72, 3.41]2.48+0.74 [-0.49, 2.33]3.12 [1.99, 3.76]23% [3%, 38%]50%64%+0.46+0.432026-08-09 → 2026-08-30
tmin12Znearest365d22 1 QC2.53 [1.68, 3.40]2.48+0.74 [-0.53, 2.40]3.12 [1.97, 3.79]23% [0%, 42%]50%64%+0.46+0.432026-08-09 → 2026-08-30
tmin12Znearestall22 1 QC2.53 [1.70, 3.44]2.48+0.74 [-0.60, 2.06]3.12 [2.00, 3.75]23% [0%, 43%]50%64%+0.46+0.432026-08-09 → 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 8, 00Z bilinear tmax+20+100-10-202026-08-09: -5.95 °F2026-08-10: -3.68 °F2026-08-11: -3.61 °F2026-08-12: -10.41 °F2026-08-13: -2.59 °F2026-08-14: -8.05 °F2026-08-15: -4.5 °F2026-08-16: -2.43 °F2026-08-17: -3.07 °F2026-08-18: -1.99 °F2026-08-19: -3.97 °F2026-08-20: +0.53 °F2026-08-21: -5.19 °F2026-08-22: +0.62 °F2026-08-23: -3.97 °F2026-08-24: -7.25 °F2026-08-25: -7.08 °F2026-08-26: -5.42 °F2026-08-27: -1.07 °F2026-08-28: -5.21 °F2026-08-29: -6.24 °F2026-08-30: -2.07 °F2026-08-092026-08-30°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 (22 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-2.07
2026-08-29-6.24
2026-08-28-5.21
2026-08-27-1.07
2026-08-26-5.42
2026-08-25-7.08
2026-08-24-7.25
2026-08-23-3.97
2026-08-22+0.62
2026-08-21-5.19
2026-08-20+0.53
2026-08-19-3.97
2026-08-18-1.99
2026-08-17-3.07
2026-08-16-2.43
2026-08-15-4.50
2026-08-14-8.05
2026-08-13-2.59
2026-08-12-10.41
2026-08-11-3.61
2026-08-10-3.68
2026-08-09-5.95

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KEWR, lead day 8-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 0 days-12 to -10 °F: 1 day-10 to -8 °F: 1 day-8 to -6 °F: 3 days-6 to -4 °F: 5 days-4 to -2 °F: 8 days-2 to 0 °F: 2 days0 to 2 °F: 2 days2 to 4 °F: 0 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| 3.97 · P90 |e| 7.24 °F-200+20 °Fn = 22 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
-14.00-12.000
-12.00-10.001
-10.00-8.001
-8.00-6.003
-6.00-4.005
-4.00-2.008
-2.00+0.002
+0.00+2.002
+2.00+4.000
+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
2026-08224.31 -4.21

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22

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 22 +0.75 [-0.66, 2.24] no
GraphCast (IFS init) 22 -0.29 [-1.87, 1.08] no
ECMWF IFS HRES 17 +0.42 [-1.16, 1.75] no
Persistence (baseline) 22 -0.05 [-1.98, 1.84] no

Cite this page

ShortCastCheck, KEWR aifs_single lead 8, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KEWR/model/aifs_single/lead/8/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KEWR (Newark Liberty), model aifs_single, lead day 8. 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/8/

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