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

Newark Liberty · NCEP GFS · lead day 7

KEWR · gfs · lead 7

Target day = initialization date + 7 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
tmax00Zbilinear30d23 1 QC2.73 [1.99, 3.40]2.80-1.00 [-2.26, 0.66]3.63 [2.66, 4.49]30% [12%, 48%]39%61%+0.35+0.262026-08-08 → 2026-08-30
tmax00Zbilinear90d23 1 QC2.73 [1.80, 3.43]2.80-1.00 [-2.28, 1.19]3.63 [2.50, 4.45]30% [11%, 50%]39%61%+0.35+0.262026-08-08 → 2026-08-30
tmax00Zbilinear365d23 1 QC2.73 [1.88, 3.48]2.80-1.00 [-2.36, 1.11]3.63 [2.46, 4.56]30% [10%, 50%]39%61%+0.35+0.262026-08-08 → 2026-08-30
tmax00Zbilinearall23 1 QC2.73 [1.84, 3.56]2.80-1.00 [-2.29, 1.07]3.63 [2.48, 4.60]30% [7%, 50%]39%61%+0.35+0.262026-08-08 → 2026-08-30
tmax00Znearest30d23 1 QC3.09 [2.16, 3.98]3.07+0.12 [-1.61, 1.97]3.97 [2.69, 4.95]26% [8%, 43%]48%57%+0.26+0.182026-08-08 → 2026-08-30
tmax00Znearest90d23 1 QC3.09 [2.00, 4.17]3.07+0.12 [-1.62, 2.72]3.97 [2.45, 5.00]26% [0%, 44%]48%57%+0.26+0.182026-08-08 → 2026-08-30
tmax00Znearest365d23 1 QC3.09 [1.97, 4.23]3.07+0.12 [-1.94, 2.38]3.97 [2.39, 5.05]26% [0%, 44%]48%57%+0.26+0.182026-08-08 → 2026-08-30
tmax00Znearestall23 1 QC3.09 [1.99, 4.29]3.07+0.12 [-1.78, 2.48]3.97 [2.39, 5.18]26% [0%, 44%]48%57%+0.26+0.182026-08-08 → 2026-08-30
tmax12Zbilinear30d23 1 QC3.64 [2.59, 4.70]3.70-0.36 [-2.00, 1.62]4.50 [3.21, 5.54]17% [5%, 29%]35%43%+0.13+0.012026-08-08 → 2026-08-30
tmax12Zbilinear90d23 1 QC3.64 [2.57, 4.70]3.70-0.36 [-2.00, 2.29]4.50 [3.04, 5.65]17% [0%, 29%]35%43%+0.13+0.012026-08-08 → 2026-08-30
tmax12Zbilinear365d23 1 QC3.64 [2.37, 4.74]3.70-0.36 [-2.14, 2.02]4.50 [2.93, 5.66]17% [0%, 29%]35%43%+0.13+0.012026-08-08 → 2026-08-30
tmax12Zbilinearall23 1 QC3.64 [2.27, 4.75]3.70-0.36 [-2.34, 2.51]4.50 [2.80, 5.70]17% [0%, 29%]35%43%+0.13+0.012026-08-08 → 2026-08-30
tmax12Znearest30d23 1 QC4.05 [2.91, 5.22]3.85+0.90 [-0.83, 2.98]4.91 [3.60, 5.97]17% [8%, 27%]30%39%+0.03-0.022026-08-08 → 2026-08-30
tmax12Znearest90d23 1 QC4.05 [2.83, 5.29]3.85+0.90 [-0.87, 3.84]4.91 [3.50, 6.01]17% [4%, 26%]30%39%+0.03-0.022026-08-08 → 2026-08-30
tmax12Znearest365d23 1 QC4.05 [2.66, 5.24]3.85+0.90 [-1.04, 3.40]4.91 [3.14, 6.01]17% [0%, 27%]30%39%+0.03-0.022026-08-08 → 2026-08-30
tmax12Znearestall23 1 QC4.05 [2.61, 5.28]3.85+0.90 [-1.20, 3.90]4.91 [3.13, 6.10]17% [0%, 29%]30%39%+0.03-0.022026-08-08 → 2026-08-30
tmin00Zbilinear30d23 1 QC4.33 [3.15, 5.69]3.03+3.64 [2.05, 5.46]5.27 [3.92, 6.47]13% [0%, 22%]26%39%-0.03+0.222026-08-08 → 2026-08-30
tmin00Zbilinear90d23 1 QC4.33 [3.09, 5.85]3.03+3.64 [2.00, 5.68]5.27 [3.94, 6.63]13% [0%, 23%]26%39%-0.03+0.222026-08-08 → 2026-08-30
tmin00Zbilinear365d23 1 QC4.33 [3.07, 5.81]3.03+3.64 [1.88, 5.70]5.27 [3.85, 6.60]13% [0%, 24%]26%39%-0.03+0.222026-08-08 → 2026-08-30
tmin00Zbilinearall23 1 QC4.33 [2.92, 5.89]3.03+3.64 [1.69, 5.85]5.27 [3.63, 6.61]13% [0%, 24%]26%39%-0.03+0.222026-08-08 → 2026-08-30
tmin00Znearest30d23 1 QC3.83 [2.78, 5.08]3.11+2.67 [1.05, 4.52]4.76 [3.51, 5.89]13% [0%, 24%]35%52%+0.09+0.202026-08-08 → 2026-08-30
tmin00Znearest90d23 1 QC3.83 [2.74, 5.32]3.11+2.67 [0.97, 4.89]4.76 [3.37, 6.12]13% [0%, 25%]35%52%+0.09+0.202026-08-08 → 2026-08-30
tmin00Znearest365d23 1 QC3.83 [2.74, 5.30]3.11+2.67 [0.84, 4.83]4.76 [3.37, 6.10]13% [0%, 25%]35%52%+0.09+0.202026-08-08 → 2026-08-30
tmin00Znearestall23 1 QC3.83 [2.59, 5.27]3.11+2.67 [0.72, 5.20]4.76 [3.22, 6.01]13% [0%, 26%]35%52%+0.09+0.202026-08-08 → 2026-08-30
tmin12Zbilinear30d23 1 QC4.57 [3.55, 5.85]3.47+3.46 [2.01, 5.43]5.47 [4.35, 6.63]13% [4%, 21%]26%30%-0.08+0.112026-08-08 → 2026-08-30
tmin12Zbilinear90d23 1 QC4.57 [3.52, 6.36]3.47+3.46 [2.08, 6.23]5.47 [4.34, 7.07]13% [0%, 21%]26%30%-0.08+0.112026-08-08 → 2026-08-30
tmin12Zbilinear365d23 1 QC4.57 [3.45, 6.12]3.47+3.46 [1.86, 5.83]5.47 [4.32, 6.79]13% [0%, 21%]26%30%-0.08+0.112026-08-08 → 2026-08-30
tmin12Zbilinearall23 1 QC4.57 [3.36, 6.22]3.47+3.46 [1.79, 6.06]5.47 [4.07, 6.83]13% [0%, 22%]26%30%-0.08+0.112026-08-08 → 2026-08-30
tmin12Znearest30d23 1 QC4.15 [3.17, 5.32]3.47+2.60 [1.15, 4.56]5.04 [4.02, 6.11]13% [0%, 28%]26%43%+0.02+0.112026-08-08 → 2026-08-30
tmin12Znearest90d23 1 QC4.15 [3.11, 5.72]3.47+2.60 [1.25, 5.36]5.04 [3.96, 6.49]13% [0%, 29%]26%43%+0.02+0.112026-08-08 → 2026-08-30
tmin12Znearest365d23 1 QC4.15 [3.07, 5.48]3.47+2.60 [1.06, 4.97]5.04 [3.97, 6.27]13% [0%, 29%]26%43%+0.02+0.112026-08-08 → 2026-08-30
tmin12Znearestall23 1 QC4.15 [3.02, 5.56]3.47+2.60 [0.96, 5.16]5.04 [3.78, 6.33]13% [0%, 30%]26%43%+0.02+0.112026-08-08 → 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 KEWR, lead day 7, 00Z bilinear tmax+10+50-5-102026-08-08: +2.42 °F2026-08-09: -0.05 °F2026-08-10: +5.74 °F2026-08-11: +3.04 °F2026-08-12: +0.12 °F2026-08-13: -4.28 °F2026-08-14: -4.01 °F2026-08-15: -1.48 °F2026-08-16: +0.28 °F2026-08-17: +0.48 °F2026-08-18: -4.51 °F2026-08-19: -3.73 °F2026-08-20: -3.07 °F2026-08-21: +2.81 °F2026-08-22: +2.58 °F2026-08-23: +2.05 °F2026-08-24: -8.15 °F2026-08-25: -1.27 °F2026-08-26: -8.86 °F2026-08-27: -0.72 °F2026-08-28: +0.34 °F2026-08-29: +0.07 °F2026-08-30: -2.78 °F2026-08-082026-08-30°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 (23 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-2.78
2026-08-29+0.07
2026-08-28+0.34
2026-08-27-0.72
2026-08-26-8.86
2026-08-25-1.27
2026-08-24-8.15
2026-08-23+2.05
2026-08-22+2.58
2026-08-21+2.81
2026-08-20-3.07
2026-08-19-3.73
2026-08-18-4.51
2026-08-17+0.48
2026-08-16+0.28
2026-08-15-1.48
2026-08-14-4.01
2026-08-13-4.28
2026-08-12+0.12
2026-08-11+3.04
2026-08-10+5.74
2026-08-09-0.05
2026-08-08+2.42

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KEWR, lead day 7-10 to -9 °F: 0 days-9 to -8 °F: 2 days-8 to -7 °F: 0 days-7 to -6 °F: 0 days-6 to -5 °F: 0 days-5 to -4 °F: 3 days-4 to -3 °F: 2 days-3 to -2 °F: 1 day-2 to -1 °F: 2 days-1 to 0 °F: 2 days0 to 1 °F: 5 days1 to 2 °F: 0 days2 to 3 °F: 4 days3 to 4 °F: 1 day4 to 5 °F: 0 days5 to 6 °F: 1 day6 to 7 °F: 0 days7 to 8 °F: 0 days8 to 9 °F: 0 days9 to 10 °F: 0 daysdashed: P50 |e| 2.58 · P90 |e| 5.5 °F-100+10 °Fn = 23 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
-9.00-8.002
-8.00-7.000
-7.00-6.000
-6.00-5.000
-5.00-4.003
-4.00-3.002
-3.00-2.001
-2.00-1.002
-1.00+0.002
+0.00+1.005
+1.00+2.000
+2.00+3.004
+3.00+4.001
+4.00+5.000
+5.00+6.001
+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
2026-08232.73 -1.00

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-08 → 2026-08-30 23
NCEP GFS2026-08-08 → 2026-08-30 23
NCEP GFS2026-08-08 → 2026-08-30 23
NCEP GFS2026-08-08 → 2026-08-30 23

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 23 -1.13 [-2.27, -0.18] yes
GraphCast (IFS init) 23 -1.55 [-2.68, -0.83] yes
ECMWF IFS HRES 18 -0.41 [-3.27, 0.65] no
Persistence (baseline) 23 -1.44 [-2.78, -0.19] yes

Cite this page

ShortCastCheck, KEWR gfs lead 7, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KEWR/model/gfs/lead/7/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KEWR (Newark Liberty), model gfs, lead day 7. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KEWR/model/gfs/lead/7/

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