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 7

KNYC · 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 QC4.16 [2.82, 6.02]3.52+3.00 [1.42, 5.53]5.09 [3.46, 6.92]17% [4%, 33%]26%39%-0.17-0.062026-08-08 → 2026-08-30
tmax00Zbilinear90d23 1 QC4.16 [2.79, 6.62]3.52+3.00 [1.39, 6.29]5.09 [3.29, 7.47]17% [0%, 35%]26%39%-0.17-0.062026-08-08 → 2026-08-30
tmax00Zbilinear365d23 1 QC4.16 [2.72, 6.41]3.52+3.00 [1.30, 6.07]5.09 [3.24, 7.22]17% [0%, 36%]26%39%-0.17-0.062026-08-08 → 2026-08-30
tmax00Zbilinearall23 1 QC4.16 [2.67, 6.37]3.52+3.00 [1.35, 6.11]5.09 [3.22, 7.22]17% [0%, 38%]26%39%-0.17-0.062026-08-08 → 2026-08-30
tmax00Znearest30d23 1 QC4.23 [2.94, 6.12]3.50+3.18 [1.60, 5.66]5.17 [3.59, 7.03]9% [0%, 18%]30%43%-0.19-0.062026-08-08 → 2026-08-30
tmax00Znearest90d23 1 QC4.23 [2.93, 6.70]3.50+3.18 [1.60, 6.45]5.17 [3.45, 7.58]9% [0%, 19%]30%43%-0.19-0.062026-08-08 → 2026-08-30
tmax00Znearest365d23 1 QC4.23 [2.85, 6.43]3.50+3.18 [1.50, 6.22]5.17 [3.39, 7.27]9% [0%, 19%]30%43%-0.19-0.062026-08-08 → 2026-08-30
tmax00Znearestall23 1 QC4.23 [2.80, 6.47]3.50+3.18 [1.56, 6.25]5.17 [3.38, 7.28]9% [0%, 19%]30%43%-0.19-0.062026-08-08 → 2026-08-30
tmax12Zbilinear30d23 1 QC5.29 [4.18, 7.05]3.86+3.61 [1.40, 6.46]6.00 [4.72, 7.69]9% [0%, 20%]13%22%-0.48-0.162026-08-08 → 2026-08-30
tmax12Zbilinear90d23 1 QC5.29 [4.14, 7.93]3.86+3.61 [1.38, 7.24]6.00 [4.60, 8.35]9% [0%, 20%]13%22%-0.48-0.162026-08-08 → 2026-08-30
tmax12Zbilinear365d23 1 QC5.29 [4.11, 7.63]3.86+3.61 [1.10, 7.08]6.00 [4.53, 8.13]9% [0%, 21%]13%22%-0.48-0.162026-08-08 → 2026-08-30
tmax12Zbilinearall23 1 QC5.29 [4.08, 7.82]3.86+3.61 [1.17, 7.53]6.00 [4.52, 8.25]9% [0%, 22%]13%22%-0.48-0.162026-08-08 → 2026-08-30
tmax12Znearest30d23 1 QC5.42 [4.27, 7.17]3.92+3.77 [1.62, 6.59]6.12 [4.85, 7.75]4% [0%, 13%]13%22%-0.52-0.182026-08-08 → 2026-08-30
tmax12Znearest90d23 1 QC5.42 [4.25, 7.91]3.92+3.77 [1.59, 7.42]6.12 [4.75, 8.38]4% [0%, 13%]13%22%-0.52-0.182026-08-08 → 2026-08-30
tmax12Znearest365d23 1 QC5.42 [4.27, 7.85]3.92+3.77 [1.37, 7.09]6.12 [4.70, 8.29]4% [0%, 14%]13%22%-0.52-0.182026-08-08 → 2026-08-30
tmax12Znearestall23 1 QC5.42 [4.28, 7.84]3.92+3.77 [1.39, 7.45]6.12 [4.70, 8.31]4% [0%, 14%]13%22%-0.52-0.182026-08-08 → 2026-08-30
tmin00Zbilinear30d23 1 QC5.37 [3.87, 6.85]2.95+4.93 [3.38, 6.57]6.29 [4.59, 7.71]9% [0%, 22%]13%17%-0.55+0.082026-08-08 → 2026-08-30
tmin00Zbilinear90d23 1 QC5.37 [3.81, 6.97]2.95+4.93 [3.32, 6.79]6.29 [4.51, 7.83]9% [0%, 22%]13%17%-0.55+0.082026-08-08 → 2026-08-30
tmin00Zbilinear365d23 1 QC5.37 [3.83, 7.14]2.95+4.93 [3.22, 6.95]6.29 [4.54, 7.94]9% [0%, 22%]13%17%-0.55+0.082026-08-08 → 2026-08-30
tmin00Zbilinearall23 1 QC5.37 [3.72, 7.17]2.95+4.93 [3.22, 6.95]6.29 [4.45, 7.98]9% [0%, 24%]13%17%-0.55+0.082026-08-08 → 2026-08-30
tmin00Znearest30d23 1 QC5.65 [4.13, 7.16]3.00+5.25 [3.73, 6.83]6.54 [4.81, 8.03]4% [0%, 12%]13%17%-0.62+0.072026-08-08 → 2026-08-30
tmin00Znearest90d23 1 QC5.65 [4.11, 7.24]3.00+5.25 [3.70, 6.92]6.54 [4.76, 8.12]4% [0%, 12%]13%17%-0.62+0.072026-08-08 → 2026-08-30
tmin00Znearest365d23 1 QC5.65 [4.12, 7.36]3.00+5.25 [3.58, 7.06]6.54 [4.79, 8.22]4% [0%, 13%]13%17%-0.62+0.072026-08-08 → 2026-08-30
tmin00Znearestall23 1 QC5.65 [4.02, 7.37]3.00+5.25 [3.57, 7.10]6.54 [4.69, 8.30]4% [0%, 14%]13%17%-0.62+0.072026-08-08 → 2026-08-30
tmin12Zbilinear30d23 1 QC5.55 [4.51, 6.81]3.00+4.93 [3.56, 6.60]6.34 [4.99, 7.56]0% [0%, 0%]4%22%-0.60+0.072026-08-08 → 2026-08-30
tmin12Zbilinear90d23 1 QC5.55 [4.43, 7.19]3.00+4.93 [3.58, 7.12]6.34 [4.87, 7.96]0% [0%, 0%]4%22%-0.60+0.072026-08-08 → 2026-08-30
tmin12Zbilinear365d23 1 QC5.55 [4.47, 7.19]3.00+4.93 [3.42, 7.02]6.34 [4.91, 7.86]0% [0%, 0%]4%22%-0.60+0.072026-08-08 → 2026-08-30
tmin12Zbilinearall23 1 QC5.55 [4.33, 7.04]3.00+4.93 [3.51, 7.04]6.34 [4.68, 7.77]0% [0%, 0%]4%22%-0.60+0.072026-08-08 → 2026-08-30
tmin12Znearest30d23 1 QC5.73 [4.68, 6.99]3.01+5.17 [3.81, 6.79]6.54 [5.20, 7.74]0% [0%, 0%]4%17%-0.65+0.062026-08-08 → 2026-08-30
tmin12Znearest90d23 1 QC5.73 [4.60, 7.36]3.01+5.17 [3.84, 7.32]6.54 [5.09, 8.13]0% [0%, 0%]4%17%-0.65+0.062026-08-08 → 2026-08-30
tmin12Znearest365d23 1 QC5.73 [4.63, 7.37]3.01+5.17 [3.70, 7.19]6.54 [5.13, 8.06]0% [0%, 0%]4%17%-0.65+0.062026-08-08 → 2026-08-30
tmin12Znearestall23 1 QC5.73 [4.53, 7.23]3.01+5.17 [3.77, 7.23]6.54 [4.89, 7.98]0% [0%, 0%]4%17%-0.65+0.062026-08-08 → 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 KNYC, lead day 7, 00Z bilinear tmax+20+100-10-202026-08-08: +8.78 °F2026-08-09: +5.32 °F2026-08-10: +12.36 °F2026-08-11: +7.26 °F2026-08-12: +4.7 °F2026-08-13: -1.29 °F2026-08-14: -0.24 °F2026-08-15: +0.98 °F2026-08-16: +2.03 °F2026-08-17: +5.64 °F2026-08-18: -3.39 °F2026-08-19: +0.6 °F2026-08-20: -2.57 °F2026-08-21: +7.49 °F2026-08-22: +6.58 °F2026-08-23: +5.79 °F2026-08-24: -3.45 °F2026-08-25: +1.56 °F2026-08-26: -2.31 °F2026-08-27: +3.39 °F2026-08-28: +4.37 °F2026-08-29: +4.83 °F2026-08-30: +0.7 °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+0.70
2026-08-29+4.83
2026-08-28+4.37
2026-08-27+3.39
2026-08-26-2.31
2026-08-25+1.56
2026-08-24-3.45
2026-08-23+5.79
2026-08-22+6.58
2026-08-21+7.49
2026-08-20-2.57
2026-08-19+0.60
2026-08-18-3.39
2026-08-17+5.64
2026-08-16+2.03
2026-08-15+0.98
2026-08-14-0.24
2026-08-13-1.29
2026-08-12+4.70
2026-08-11+7.26
2026-08-10+12.36
2026-08-09+5.32
2026-08-08+8.78

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KNYC, lead day 7-20 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: 0 days-10 to -8 °F: 0 days-8 to -6 °F: 0 days-6 to -4 °F: 0 days-4 to -2 °F: 4 days-2 to 0 °F: 2 days0 to 2 °F: 4 days2 to 4 °F: 2 days4 to 6 °F: 6 days6 to 8 °F: 3 days8 to 10 °F: 1 day10 to 12 °F: 0 days12 to 14 °F: 1 day14 to 16 °F: 0 days16 to 18 °F: 0 days18 to 20 °F: 0 daysdashed: P50 |e| 3.45 · P90 |e| 7.44 °F-200+20 °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
-20.00-18.000
-18.00-16.000
-16.00-14.000
-14.00-12.000
-12.00-10.000
-10.00-8.000
-8.00-6.000
-6.00-4.000
-4.00-2.004
-2.00+0.002
+0.00+2.004
+2.00+4.002
+4.00+6.006
+6.00+8.003
+8.00+10.001
+10.00+12.000
+12.00+14.001
+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
2026-08234.16 +3.00

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 +1.97 [0.46, 4.46] yes
GraphCast (IFS init) 23 +1.78 [0.05, 4.90] yes
ECMWF IFS HRES 18 +1.12 [-1.00, 3.82] no
Persistence (baseline) 23 +0.59 [-1.15, 3.69] no

Cite this page

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

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