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 1

KNYC · gfs · lead 1

Target day = initialization date + 1 day. 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
tmax00Zbilinear30d29 1 QC3.80 [3.01, 4.78]2.22+3.18 [1.88, 4.50]4.32 [3.42, 5.20]10% [3%, 17%]21%38%-0.41+0.162026-08-02 → 2026-08-30
tmax00Zbilinear90d29 1 QC3.80 [2.72, 5.10]2.22+3.18 [1.61, 4.83]4.32 [3.21, 5.45]10% [0%, 19%]21%38%-0.41+0.162026-08-02 → 2026-08-30
tmax00Zbilinear365d29 1 QC3.80 [2.72, 5.14]2.22+3.18 [1.37, 4.97]4.32 [3.14, 5.50]10% [0%, 19%]21%38%-0.41+0.162026-08-02 → 2026-08-30
tmax00Zbilinearall29 1 QC3.80 [2.62, 5.19]2.22+3.18 [1.55, 5.02]4.32 [3.09, 5.51]10% [0%, 21%]21%38%-0.41+0.162026-08-02 → 2026-08-30
tmax00Znearest30d29 1 QC3.93 [3.13, 4.89]2.23+3.30 [2.03, 4.63]4.45 [3.54, 5.32]17% [7%, 28%]17%28%-0.46+0.162026-08-02 → 2026-08-30
tmax00Znearest90d29 1 QC3.93 [2.81, 5.21]2.23+3.30 [1.78, 4.91]4.45 [3.30, 5.59]17% [5%, 32%]17%28%-0.46+0.162026-08-02 → 2026-08-30
tmax00Znearest365d29 1 QC3.93 [2.78, 5.28]2.23+3.30 [1.58, 5.11]4.45 [3.22, 5.64]17% [5%, 31%]17%28%-0.46+0.162026-08-02 → 2026-08-30
tmax00Znearestall29 1 QC3.93 [2.75, 5.30]2.23+3.30 [1.63, 5.09]4.45 [3.23, 5.67]17% [5%, 33%]17%28%-0.46+0.162026-08-02 → 2026-08-30
tmax12Zbilinear30d29 1 QC3.77 [3.06, 4.60]2.34+2.99 [1.64, 4.32]4.23 [3.52, 5.00]3% [0%, 11%]24%38%-0.40+0.122026-08-02 → 2026-08-30
tmax12Zbilinear90d29 1 QC3.77 [2.76, 4.78]2.34+2.99 [1.41, 4.56]4.23 [3.28, 5.16]3% [0%, 15%]24%38%-0.40+0.122026-08-02 → 2026-08-30
tmax12Zbilinear365d29 1 QC3.77 [2.81, 4.84]2.34+2.99 [1.27, 4.72]4.23 [3.27, 5.16]3% [0%, 13%]24%38%-0.40+0.122026-08-02 → 2026-08-30
tmax12Zbilinearall29 1 QC3.77 [2.71, 4.83]2.34+2.99 [1.44, 4.70]4.23 [3.20, 5.17]3% [0%, 16%]24%38%-0.40+0.122026-08-02 → 2026-08-30
tmax12Znearest30d29 1 QC3.85 [3.11, 4.73]2.40+3.14 [1.82, 4.46]4.35 [3.62, 5.17]3% [0%, 11%]24%41%-0.43+0.092026-08-02 → 2026-08-30
tmax12Znearest90d29 1 QC3.85 [2.81, 4.92]2.40+3.14 [1.56, 4.72]4.35 [3.35, 5.31]3% [0%, 15%]24%41%-0.43+0.092026-08-02 → 2026-08-30
tmax12Znearest365d29 1 QC3.85 [2.85, 5.02]2.40+3.14 [1.49, 4.89]4.35 [3.38, 5.37]3% [0%, 13%]24%41%-0.43+0.092026-08-02 → 2026-08-30
tmax12Znearestall29 1 QC3.85 [2.75, 5.03]2.40+3.14 [1.61, 4.86]4.35 [3.26, 5.35]3% [0%, 16%]24%41%-0.43+0.092026-08-02 → 2026-08-30
tmin00Zbilinear30d29 1 QC4.92 [4.37, 5.40]1.50+4.92 [4.37, 5.40]5.26 [4.68, 5.79]0% [0%, 0%]3%10%-0.90+0.422026-08-02 → 2026-08-30
tmin00Zbilinear90d29 1 QC4.92 [4.27, 5.45]1.50+4.92 [4.27, 5.45]5.26 [4.59, 5.84]0% [0%, 0%]3%10%-0.90+0.422026-08-02 → 2026-08-30
tmin00Zbilinear365d29 1 QC4.92 [4.29, 5.46]1.50+4.92 [4.29, 5.46]5.26 [4.55, 5.83]0% [0%, 0%]3%10%-0.90+0.422026-08-02 → 2026-08-30
tmin00Zbilinearall29 1 QC4.92 [4.16, 5.47]1.50+4.92 [4.16, 5.47]5.26 [4.49, 5.85]0% [0%, 0%]3%10%-0.90+0.422026-08-02 → 2026-08-30
tmin00Znearest30d29 1 QC5.23 [4.67, 5.73]1.51+5.23 [4.67, 5.73]5.57 [4.98, 6.12]0% [0%, 0%]3%10%-1.02+0.422026-08-02 → 2026-08-30
tmin00Znearest90d29 1 QC5.23 [4.57, 5.78]1.51+5.23 [4.57, 5.78]5.57 [4.88, 6.16]0% [0%, 0%]3%10%-1.02+0.422026-08-02 → 2026-08-30
tmin00Znearest365d29 1 QC5.23 [4.59, 5.79]1.51+5.23 [4.59, 5.79]5.57 [4.85, 6.15]0% [0%, 0%]3%10%-1.02+0.422026-08-02 → 2026-08-30
tmin00Znearestall29 1 QC5.23 [4.46, 5.80]1.51+5.23 [4.46, 5.80]5.57 [4.77, 6.18]0% [0%, 0%]3%10%-1.02+0.422026-08-02 → 2026-08-30
tmin12Zbilinear30d29 1 QC4.37 [3.89, 4.82]1.32+4.37 [3.89, 4.82]4.66 [4.10, 5.15]0% [0%, 0%]3%24%-0.69+0.492026-08-02 → 2026-08-30
tmin12Zbilinear90d29 1 QC4.37 [3.88, 4.81]1.32+4.37 [3.88, 4.81]4.66 [4.09, 5.12]0% [0%, 0%]3%24%-0.69+0.492026-08-02 → 2026-08-30
tmin12Zbilinear365d29 1 QC4.37 [3.83, 4.85]1.32+4.37 [3.83, 4.85]4.66 [4.04, 5.16]0% [0%, 0%]3%24%-0.69+0.492026-08-02 → 2026-08-30
tmin12Zbilinearall29 1 QC4.37 [3.77, 4.84]1.32+4.37 [3.77, 4.84]4.66 [3.96, 5.18]0% [0%, 0%]3%24%-0.69+0.492026-08-02 → 2026-08-30
tmin12Znearest30d29 1 QC4.60 [4.14, 5.02]1.31+4.60 [4.14, 5.02]4.88 [4.38, 5.33]0% [0%, 0%]3%21%-0.78+0.492026-08-02 → 2026-08-30
tmin12Znearest90d29 1 QC4.60 [4.13, 5.00]1.31+4.60 [4.13, 5.00]4.88 [4.36, 5.31]0% [0%, 0%]3%21%-0.78+0.492026-08-02 → 2026-08-30
tmin12Znearest365d29 1 QC4.60 [4.08, 5.05]1.31+4.60 [4.08, 5.05]4.88 [4.30, 5.33]0% [0%, 0%]3%21%-0.78+0.492026-08-02 → 2026-08-30
tmin12Znearestall29 1 QC4.60 [4.00, 5.04]1.31+4.60 [4.00, 5.04]4.88 [4.25, 5.37]0% [0%, 0%]3%21%-0.78+0.492026-08-02 → 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 1, 00Z bilinear tmax+10+50-5-102026-08-02: +0.31 °F2026-08-03: +2.77 °F2026-08-04: +1.07 °F2026-08-05: -1.66 °F2026-08-06: +4.54 °F2026-08-07: +4.32 °F2026-08-08: +6.26 °F2026-08-09: +7.14 °F2026-08-10: +6.41 °F2026-08-11: +7.76 °F2026-08-12: +5.18 °F2026-08-13: +3.51 °F2026-08-14: +3.95 °F2026-08-15: +2.66 °F2026-08-16: -0.67 °F2026-08-17: +3.45 °F2026-08-18: +2.65 °F2026-08-19: +4.31 °F2026-08-20: -5.12 °F2026-08-21: +3.3 °F2026-08-22: -1.3 °F2026-08-23: +4.68 °F2026-08-24: +2.95 °F2026-08-25: -0.27 °F2026-08-26: +2.55 °F2026-08-27: +4.37 °F2026-08-28: +3.75 °F2026-08-29: +5.87 °F2026-08-30: +7.47 °F2026-08-022026-08-30°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 (29 days, newest first) · download CSV
Climatological dayError °F
2026-08-30+7.47
2026-08-29+5.87
2026-08-28+3.75
2026-08-27+4.37
2026-08-26+2.55
2026-08-25-0.27
2026-08-24+2.95
2026-08-23+4.68
2026-08-22-1.30
2026-08-21+3.30
2026-08-20-5.12
2026-08-19+4.31
2026-08-18+2.65
2026-08-17+3.45
2026-08-16-0.67
2026-08-15+2.66
2026-08-14+3.95
2026-08-13+3.51
2026-08-12+5.18
2026-08-11+7.76
2026-08-10+6.41
2026-08-09+7.14
2026-08-08+6.26
2026-08-07+4.32
2026-08-06+4.54
2026-08-05-1.66
2026-08-04+1.07
2026-08-03+2.77
2026-08-02+0.31

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KNYC, lead day 1-10 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: 1 day-5 to -4 °F: 0 days-4 to -3 °F: 0 days-3 to -2 °F: 0 days-2 to -1 °F: 2 days-1 to 0 °F: 2 days0 to 1 °F: 1 day1 to 2 °F: 1 day2 to 3 °F: 5 days3 to 4 °F: 5 days4 to 5 °F: 5 days5 to 6 °F: 2 days6 to 7 °F: 2 days7 to 8 °F: 3 days8 to 9 °F: 0 days9 to 10 °F: 0 daysdashed: P50 |e| 3.75 · P90 |e| 6.56 °F-100+10 °Fn = 29 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
-6.00-5.001
-5.00-4.000
-4.00-3.000
-3.00-2.000
-2.00-1.002
-1.00+0.002
+0.00+1.001
+1.00+2.001
+2.00+3.005
+3.00+4.005
+4.00+5.005
+5.00+6.002
+6.00+7.002
+7.00+8.003
+8.00+9.000
+9.00+10.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08293.80 +3.18

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-02 → 2026-08-30 29
NCEP GFS2026-08-02 → 2026-08-30 29
NCEP GFS2026-08-02 → 2026-08-30 29
NCEP GFS2026-08-02 → 2026-08-30 29

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 29 +2.54 [1.55, 3.73] yes
Aurora (GFS init) 1 +7.23 [7.23, 7.23] yes
Aurora (IFS init) 2 +6.39 [5.48, 7.30] yes
FourCastNet v2 (GFS init) 1 +6.87 [6.87, 6.87] yes
FourCastNet v2 (IFS init) 2 +4.66 [2.67, 6.64] yes
GraphCast (GFS init) 1 +5.29 [5.29, 5.29] yes
GraphCast (IFS init) 27 +1.71 [0.24, 3.56] yes
ECMWF IFS HRES 23 +0.94 [-0.01, 1.91] no
Pangu-Weather (GFS init) 1 +3.03 [3.03, 3.03] yes
Pangu-Weather (IFS init) 2 +2.95 [2.33, 3.57] yes
Persistence (baseline) 29 +1.11 [-0.29, 2.67] no

Cite this page

ShortCastCheck, KNYC gfs lead 1, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KNYC/model/gfs/lead/1/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KNYC (New York Central Park), model gfs, lead day 1. 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/1/

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