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

New York Central Park · NCEP GFS · lead day 0

KNYC · gfs · lead 0

Target day = initialization date + 0 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
tmax00Zbilinear30d30 1 QC3.36 [2.58, 4.25]1.81+3.06 [2.01, 4.16]3.80 [2.97, 4.55]13% [3%, 23%]23%43%——2026-08-01 → 2026-08-30
tmax00Zbilinear90d30 1 QC3.36 [2.30, 4.46]1.81+3.06 [1.79, 4.39]3.80 [2.68, 4.75]13% [0%, 27%]23%43%——2026-08-01 → 2026-08-30
tmax00Zbilinear365d30 1 QC3.36 [2.19, 4.63]1.81+3.06 [1.63, 4.62]3.80 [2.53, 4.86]13% [0%, 29%]23%43%——2026-08-01 → 2026-08-30
tmax00Zbilinearall30 1 QC3.36 [2.13, 4.53]1.81+3.06 [1.68, 4.53]3.80 [2.45, 4.76]13% [0%, 30%]23%43%——2026-08-01 → 2026-08-30
tmax00Znearest30d30 1 QC3.47 [2.65, 4.38]1.90+3.16 [2.14, 4.27]3.94 [3.12, 4.70]17% [3%, 33%]23%40%——2026-08-01 → 2026-08-30
tmax00Znearest90d30 1 QC3.47 [2.35, 4.60]1.90+3.16 [1.90, 4.53]3.94 [2.82, 4.89]17% [0%, 40%]23%40%——2026-08-01 → 2026-08-30
tmax00Znearest365d30 1 QC3.47 [2.25, 4.77]1.90+3.16 [1.70, 4.76]3.94 [2.69, 5.02]17% [0%, 39%]23%40%——2026-08-01 → 2026-08-30
tmax00Znearestall30 1 QC3.47 [2.18, 4.64]1.90+3.16 [1.79, 4.64]3.94 [2.61, 4.92]17% [0%, 44%]23%40%——2026-08-01 → 2026-08-30
tmin00Zbilinear30d30 1 QC4.57 [4.08, 5.13]1.34+4.57 [4.08, 5.13]4.87 [4.28, 5.53]0% [0%, 0%]7%20%——2026-08-01 → 2026-08-30
tmin00Zbilinear90d30 1 QC4.57 [4.01, 5.15]1.34+4.57 [4.01, 5.15]4.87 [4.24, 5.54]0% [0%, 0%]7%20%——2026-08-01 → 2026-08-30
tmin00Zbilinear365d30 1 QC4.57 [3.97, 5.20]1.34+4.57 [3.97, 5.20]4.87 [4.17, 5.57]0% [0%, 0%]7%20%——2026-08-01 → 2026-08-30
tmin00Zbilinearall30 1 QC4.57 [3.97, 5.20]1.34+4.57 [3.97, 5.20]4.87 [4.18, 5.60]0% [0%, 0%]7%20%——2026-08-01 → 2026-08-30
tmin00Znearest30d30 1 QC4.85 [4.35, 5.42]1.38+4.85 [4.35, 5.42]5.15 [4.55, 5.82]0% [0%, 0%]3%10%——2026-08-01 → 2026-08-30
tmin00Znearest90d30 1 QC4.85 [4.27, 5.43]1.38+4.85 [4.27, 5.43]5.15 [4.49, 5.85]0% [0%, 0%]3%10%——2026-08-01 → 2026-08-30
tmin00Znearest365d30 1 QC4.85 [4.23, 5.49]1.38+4.85 [4.23, 5.49]5.15 [4.44, 5.86]0% [0%, 0%]3%10%——2026-08-01 → 2026-08-30
tmin00Znearestall30 1 QC4.85 [4.25, 5.48]1.38+4.85 [4.25, 5.48]5.15 [4.47, 5.89]0% [0%, 0%]3%10%——2026-08-01 → 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 KNYC, lead day 0, 00Z bilinear tmax+10+50-5-102026-08-01: +1.17 °F2026-08-02: +0.56 °F2026-08-03: +0.64 °F2026-08-04: +2.81 °F2026-08-05: +1.52 °F2026-08-06: +4.71 °F2026-08-07: +3.7 °F2026-08-08: +6.81 °F2026-08-09: +6.46 °F2026-08-10: +4.8 °F2026-08-11: +4.39 °F2026-08-12: +5.3 °F2026-08-13: +3.97 °F2026-08-14: +5.05 °F2026-08-15: +2.27 °F2026-08-16: +2.22 °F2026-08-17: +3.83 °F2026-08-18: -2.78 °F2026-08-19: +3.16 °F2026-08-20: -0.91 °F2026-08-21: +3.15 °F2026-08-22: +2.56 °F2026-08-23: +1.09 °F2026-08-24: +3.47 °F2026-08-25: -0.84 °F2026-08-26: +2.31 °F2026-08-27: +5.45 °F2026-08-28: +3.61 °F2026-08-29: +5.21 °F2026-08-30: +6.13 °F2026-08-012026-08-30°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 (30 days, newest first) · download CSV
Climatological dayError °F
2026-08-30+6.13
2026-08-29+5.21
2026-08-28+3.61
2026-08-27+5.45
2026-08-26+2.31
2026-08-25-0.84
2026-08-24+3.47
2026-08-23+1.09
2026-08-22+2.56
2026-08-21+3.15
2026-08-20-0.91
2026-08-19+3.16
2026-08-18-2.78
2026-08-17+3.83
2026-08-16+2.22
2026-08-15+2.27
2026-08-14+5.05
2026-08-13+3.97
2026-08-12+5.30
2026-08-11+4.39
2026-08-10+4.80
2026-08-09+6.46
2026-08-08+6.81
2026-08-07+3.70
2026-08-06+4.71
2026-08-05+1.52
2026-08-04+2.81
2026-08-03+0.64
2026-08-02+0.56
2026-08-01+1.17

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KNYC, lead day 0-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 0 days-6 to -5 °F: 0 days-5 to -4 °F: 0 days-4 to -3 °F: 0 days-3 to -2 °F: 1 day-2 to -1 °F: 0 days-1 to 0 °F: 2 days0 to 1 °F: 2 days1 to 2 °F: 3 days2 to 3 °F: 5 days3 to 4 °F: 7 days4 to 5 °F: 3 days5 to 6 °F: 4 days6 to 7 °F: 3 days7 to 8 °F: 0 days8 to 9 °F: 0 days9 to 10 °F: 0 daysdashed: P50 |e| 3.32 · P90 |e| 5.52 °F-100+10 °Fn = 30 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
-9.00-8.000
-8.00-7.000
-7.00-6.000
-6.00-5.000
-5.00-4.000
-4.00-3.000
-3.00-2.001
-2.00-1.000
-1.00+0.002
+0.00+1.002
+1.00+2.003
+2.00+3.005
+3.00+4.007
+4.00+5.003
+5.00+6.004
+6.00+7.003
+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
2026-08303.36 +3.06

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-01 → 2026-08-30 30
NCEP GFS2026-08-01 → 2026-08-30 30

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 30 +1.90 [0.92, 2.89] yes
Aurora (GFS init) 2 +4.72 [4.67, 4.77] yes
Aurora (IFS init) 3 +2.80 [-0.85, 4.95] no
FourCastNet v2 (GFS init) 2 +3.98 [2.99, 4.97] yes
FourCastNet v2 (IFS init) 3 +2.09 [-2.62, 5.38] no
GraphCast (GFS init) 2 +4.70 [4.43, 4.97] yes
GraphCast (IFS init) 28 +1.52 [0.13, 3.00] yes
ECMWF IFS HRES 24 +1.21 [0.56, 1.71] yes
Pangu-Weather (GFS init) 2 +1.86 [1.38, 2.34] yes
Pangu-Weather (IFS init) 3 +1.78 [1.03, 2.16] yes

Cite this page

ShortCastCheck, KNYC gfs lead 0, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KNYC/model/gfs/lead/0/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KNYC (New York Central Park), model gfs, lead day 0. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KNYC/model/gfs/lead/0/

Accessed2026-08-31 (data through 2026-08-30; page built 2026-08-31T03:52:06+00:00)

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