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

Newark Liberty · ECMWF AIFS Single · lead day 2

KEWR · aifs_single · lead 2

Target day = initialization date + 2 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
tmax00Zbilinear30d28 1 QC3.09 [2.14, 4.07]2.03-2.88 [-4.04, -1.74]3.79 [2.59, 4.72]21% [7%, 37%]43%50%-0.01+0.322026-08-03 → 2026-08-30
tmax00Zbilinear90d28 1 QC3.09 [1.96, 4.35]2.03-2.88 [-4.35, -1.62]3.79 [2.46, 5.01]21% [5%, 43%]43%50%-0.01+0.322026-08-03 → 2026-08-30
tmax00Zbilinear365d28 1 QC3.09 [1.74, 4.38]2.03-2.88 [-4.38, -1.40]3.79 [2.17, 5.01]21% [5%, 45%]43%50%-0.01+0.322026-08-03 → 2026-08-30
tmax00Zbilinearall28 1 QC3.09 [1.85, 4.51]2.03-2.88 [-4.51, -1.57]3.79 [2.30, 5.08]21% [0%, 43%]43%50%-0.01+0.322026-08-03 → 2026-08-30
tmax00Znearest30d28 1 QC3.09 [2.10, 4.07]2.06-2.87 [-4.03, -1.69]3.80 [2.61, 4.71]21% [7%, 37%]46%54%-0.00+0.312026-08-03 → 2026-08-30
tmax00Znearest90d28 1 QC3.09 [1.94, 4.32]2.06-2.87 [-4.30, -1.59]3.80 [2.45, 4.98]21% [5%, 43%]46%54%-0.00+0.312026-08-03 → 2026-08-30
tmax00Znearest365d28 1 QC3.09 [1.72, 4.38]2.06-2.87 [-4.38, -1.39]3.80 [2.15, 4.98]21% [5%, 45%]46%54%-0.00+0.312026-08-03 → 2026-08-30
tmax00Znearestall28 1 QC3.09 [1.83, 4.54]2.06-2.87 [-4.54, -1.53]3.80 [2.29, 5.06]21% [0%, 43%]46%54%-0.00+0.312026-08-03 → 2026-08-30
tmax12Zbilinear30d28 1 QC3.18 [2.30, 4.03]1.73-3.12 [-4.00, -2.22]3.84 [2.76, 4.72]14% [4%, 25%]32%61%-0.03+0.432026-08-03 → 2026-08-30
tmax12Zbilinear90d28 1 QC3.18 [2.31, 4.23]1.73-3.12 [-4.23, -2.20]3.84 [2.77, 4.96]14% [0%, 24%]32%61%-0.03+0.432026-08-03 → 2026-08-30
tmax12Zbilinear365d28 1 QC3.18 [2.17, 4.20]1.73-3.12 [-4.20, -2.05]3.84 [2.57, 4.91]14% [0%, 25%]32%61%-0.03+0.432026-08-03 → 2026-08-30
tmax12Zbilinearall28 1 QC3.18 [2.24, 4.42]1.73-3.12 [-4.42, -2.17]3.84 [2.64, 5.06]14% [0%, 25%]32%61%-0.03+0.432026-08-03 → 2026-08-30
tmax12Znearest30d28 1 QC3.19 [2.31, 4.08]1.74-3.12 [-4.06, -2.21]3.89 [2.78, 4.79]18% [4%, 32%]29%57%-0.04+0.422026-08-03 → 2026-08-30
tmax12Znearest90d28 1 QC3.19 [2.29, 4.25]1.74-3.12 [-4.24, -2.17]3.89 [2.78, 5.01]18% [0%, 33%]29%57%-0.04+0.422026-08-03 → 2026-08-30
tmax12Znearest365d28 1 QC3.19 [2.20, 4.25]1.74-3.12 [-4.23, -2.04]3.89 [2.58, 4.96]18% [0%, 33%]29%57%-0.04+0.422026-08-03 → 2026-08-30
tmax12Znearestall28 1 QC3.19 [2.22, 4.43]1.74-3.12 [-4.40, -2.11]3.89 [2.63, 5.10]18% [0%, 33%]29%57%-0.04+0.422026-08-03 → 2026-08-30
tmin00Zbilinear30d28 1 QC2.38 [1.60, 2.97]1.88+1.82 [1.06, 2.62]2.95 [2.16, 3.60]21% [3%, 46%]43%71%+0.45+0.562026-08-03 → 2026-08-30
tmin00Zbilinear90d28 1 QC2.38 [1.46, 3.02]1.88+1.82 [0.99, 2.72]2.95 [2.09, 3.65]21% [4%, 50%]43%71%+0.45+0.562026-08-03 → 2026-08-30
tmin00Zbilinear365d28 1 QC2.38 [1.25, 3.06]1.88+1.82 [0.93, 2.77]2.95 [1.79, 3.71]21% [0%, 54%]43%71%+0.45+0.562026-08-03 → 2026-08-30
tmin00Zbilinearall28 1 QC2.38 [1.42, 3.03]1.88+1.82 [0.93, 2.66]2.95 [2.02, 3.64]21% [0%, 50%]43%71%+0.45+0.562026-08-03 → 2026-08-30
tmin00Znearest30d28 1 QC2.10 [1.65, 2.47]1.90+0.93 [0.13, 1.73]2.50 [1.91, 3.01]11% [3%, 21%]57%82%+0.51+0.552026-08-03 → 2026-08-30
tmin00Znearest90d28 1 QC2.10 [1.60, 2.55]1.90+0.93 [0.06, 1.84]2.50 [1.86, 3.07]11% [0%, 21%]57%82%+0.51+0.552026-08-03 → 2026-08-30
tmin00Znearest365d28 1 QC2.10 [1.45, 2.56]1.90+0.93 [-0.06, 1.87]2.50 [1.68, 3.12]11% [0%, 22%]57%82%+0.51+0.552026-08-03 → 2026-08-30
tmin00Znearestall28 1 QC2.10 [1.57, 2.55]1.90+0.93 [-0.03, 1.76]2.50 [1.80, 3.12]11% [0%, 20%]57%82%+0.51+0.552026-08-03 → 2026-08-30
tmin12Zbilinear30d28 1 QC2.30 [1.60, 2.86]1.66+1.84 [1.16, 2.50]2.77 [2.08, 3.29]29% [10%, 54%]39%75%+0.47+0.612026-08-03 → 2026-08-30
tmin12Zbilinear90d28 1 QC2.30 [1.43, 2.99]1.66+1.84 [1.10, 2.61]2.77 [1.87, 3.43]29% [10%, 58%]39%75%+0.47+0.612026-08-03 → 2026-08-30
tmin12Zbilinear365d28 1 QC2.30 [1.16, 3.03]1.66+1.84 [0.97, 2.65]2.77 [1.52, 3.47]29% [9%, 64%]39%75%+0.47+0.612026-08-03 → 2026-08-30
tmin12Zbilinearall28 1 QC2.30 [1.39, 3.04]1.66+1.84 [1.08, 2.55]2.77 [1.85, 3.46]29% [10%, 58%]39%75%+0.47+0.612026-08-03 → 2026-08-30
tmin12Znearest30d28 1 QC1.97 [1.41, 2.47]1.69+0.96 [0.23, 1.63]2.32 [1.73, 2.80]18% [0%, 43%]64%86%+0.55+0.612026-08-03 → 2026-08-30
tmin12Znearest90d28 1 QC1.97 [1.33, 2.61]1.69+0.96 [0.15, 1.79]2.32 [1.58, 2.91]18% [0%, 45%]64%86%+0.55+0.612026-08-03 → 2026-08-30
tmin12Znearest365d28 1 QC1.97 [1.09, 2.62]1.69+0.96 [-0.05, 1.82]2.32 [1.25, 2.95]18% [0%, 50%]64%86%+0.55+0.612026-08-03 → 2026-08-30
tmin12Znearestall28 1 QC1.97 [1.32, 2.64]1.69+0.96 [0.10, 1.72]2.32 [1.60, 2.97]18% [0%, 45%]64%86%+0.55+0.612026-08-03 → 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 2, 00Z bilinear tmax+10+50-5-102026-08-03: -8.54 °F2026-08-04: -1.46 °F2026-08-05: -5.15 °F2026-08-06: -4.33 °F2026-08-07: -7.43 °F2026-08-08: -2.47 °F2026-08-09: -1.57 °F2026-08-10: -0.91 °F2026-08-11: +0.84 °F2026-08-12: -3.09 °F2026-08-13: -1.62 °F2026-08-14: -2.1 °F2026-08-15: -1.91 °F2026-08-16: +1.26 °F2026-08-17: +0.8 °F2026-08-18: -1.22 °F2026-08-19: -4.03 °F2026-08-20: -5.25 °F2026-08-21: -3.89 °F2026-08-22: -7.18 °F2026-08-23: -3.14 °F2026-08-24: -4.46 °F2026-08-25: -4.35 °F2026-08-26: -3.84 °F2026-08-27: -0.63 °F2026-08-28: -4.16 °F2026-08-29: -0.54 °F2026-08-30: -0.38 °F2026-08-032026-08-30°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 (28 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-0.38
2026-08-29-0.54
2026-08-28-4.16
2026-08-27-0.63
2026-08-26-3.84
2026-08-25-4.35
2026-08-24-4.46
2026-08-23-3.14
2026-08-22-7.18
2026-08-21-3.89
2026-08-20-5.25
2026-08-19-4.03
2026-08-18-1.22
2026-08-17+0.80
2026-08-16+1.26
2026-08-15-1.91
2026-08-14-2.10
2026-08-13-1.62
2026-08-12-3.09
2026-08-11+0.84
2026-08-10-0.91
2026-08-09-1.57
2026-08-08-2.47
2026-08-07-7.43
2026-08-06-4.33
2026-08-05-5.15
2026-08-04-1.46
2026-08-03-8.54

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KEWR, lead day 2-10 to -9 °F: 0 days-9 to -8 °F: 1 day-8 to -7 °F: 2 days-7 to -6 °F: 0 days-6 to -5 °F: 2 days-5 to -4 °F: 5 days-4 to -3 °F: 4 days-3 to -2 °F: 2 days-2 to -1 °F: 5 days-1 to 0 °F: 4 days0 to 1 °F: 2 days1 to 2 °F: 1 day2 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| 2.78 · P90 |e| 5.83 °F-100+10 °Fn = 28 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
-10.00-9.000
-9.00-8.001
-8.00-7.002
-7.00-6.000
-6.00-5.002
-5.00-4.005
-4.00-3.004
-3.00-2.002
-2.00-1.005
-1.00+0.004
+0.00+1.002
+1.00+2.001
+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
2026-08283.09 -2.88

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-03 → 2026-08-30 28
ECMWF AIFS Single2026-08-03 → 2026-08-30 28
ECMWF AIFS Single2026-08-03 → 2026-08-30 28
ECMWF AIFS Single2026-08-03 → 2026-08-30 28

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
Aurora (IFS init) 1 -0.16 [-0.16, -0.16] yes
FourCastNet v2 (IFS init) 1 -1.70 [-1.70, -1.70] yes
NCEP GFS 28 +0.16 [-1.18, 1.23] no
GraphCast (IFS init) 26 -1.64 [-2.22, -0.81] yes
ECMWF IFS HRES 22 -0.83 [-1.65, -0.08] yes
Pangu-Weather (IFS init) 1 -1.01 [-1.01, -1.01] yes
Persistence (baseline) 28 +0.02 [-1.07, 1.22] no

Cite this page

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

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

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