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 · ECMWF AIFS Single · lead day 6

KNYC · aifs_single · lead 6

Target day = initialization date + 6 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
tmax00Zbilinear30d24 1 QC2.28 [1.77, 2.95]2.14-0.57 [-1.42, 0.46]2.66 [2.06, 3.31]21% [4%, 35%]46%75%+0.38+0.372026-08-07 → 2026-08-30
tmax00Zbilinear90d24 1 QC2.28 [1.74, 3.06]2.14-0.57 [-1.50, 0.58]2.66 [2.04, 3.38]21% [0%, 36%]46%75%+0.38+0.372026-08-07 → 2026-08-30
tmax00Zbilinear365d24 1 QC2.28 [1.69, 3.12]2.14-0.57 [-1.61, 0.59]2.66 [2.02, 3.45]21% [0%, 36%]46%75%+0.38+0.372026-08-07 → 2026-08-30
tmax00Zbilinearall24 1 QC2.28 [1.71, 2.98]2.14-0.57 [-1.47, 0.65]2.66 [2.02, 3.35]21% [0%, 36%]46%75%+0.38+0.372026-08-07 → 2026-08-30
tmax00Znearest30d24 1 QC2.23 [1.70, 2.89]2.20-0.15 [-1.04, 0.91]2.66 [2.11, 3.23]21% [4%, 35%]54%79%+0.39+0.352026-08-07 → 2026-08-30
tmax00Znearest90d24 1 QC2.23 [1.68, 3.04]2.20-0.15 [-1.12, 1.14]2.66 [2.05, 3.33]21% [0%, 36%]54%79%+0.39+0.352026-08-07 → 2026-08-30
tmax00Znearest365d24 1 QC2.23 [1.68, 3.04]2.20-0.15 [-1.21, 1.13]2.66 [2.04, 3.38]21% [0%, 36%]54%79%+0.39+0.352026-08-07 → 2026-08-30
tmax00Znearestall24 1 QC2.23 [1.68, 2.90]2.20-0.15 [-1.10, 1.18]2.66 [2.05, 3.27]21% [0%, 36%]54%79%+0.39+0.352026-08-07 → 2026-08-30
tmax12Zbilinear30d24 1 QC2.28 [1.66, 2.95]2.13-0.74 [-1.66, 0.35]3.01 [2.08, 3.77]33% [19%, 48%]58%75%+0.38+0.372026-08-07 → 2026-08-30
tmax12Zbilinear90d24 1 QC2.28 [1.60, 3.14]2.13-0.74 [-1.72, 0.52]3.01 [2.05, 3.88]33% [15%, 50%]58%75%+0.38+0.372026-08-07 → 2026-08-30
tmax12Zbilinear365d24 1 QC2.28 [1.57, 3.17]2.13-0.74 [-1.87, 0.50]3.01 [2.00, 3.98]33% [17%, 50%]58%75%+0.38+0.372026-08-07 → 2026-08-30
tmax12Zbilinearall24 1 QC2.28 [1.61, 3.09]2.13-0.74 [-1.68, 0.55]3.01 [2.04, 3.83]33% [14%, 50%]58%75%+0.38+0.372026-08-07 → 2026-08-30
tmax12Znearest30d24 1 QC2.17 [1.54, 2.90]2.15-0.30 [-1.26, 0.84]2.97 [2.11, 3.69]50% [30%, 65%]58%71%+0.41+0.372026-08-07 → 2026-08-30
tmax12Znearest90d24 1 QC2.17 [1.49, 3.04]2.15-0.30 [-1.31, 0.97]2.97 [2.07, 3.81]50% [25%, 67%]58%71%+0.41+0.372026-08-07 → 2026-08-30
tmax12Znearest365d24 1 QC2.17 [1.49, 3.13]2.15-0.30 [-1.43, 1.02]2.97 [2.04, 3.87]50% [25%, 67%]58%71%+0.41+0.372026-08-07 → 2026-08-30
tmax12Znearestall24 1 QC2.17 [1.47, 3.04]2.15-0.30 [-1.27, 0.95]2.97 [2.06, 3.78]50% [27%, 71%]58%71%+0.41+0.372026-08-07 → 2026-08-30
tmin00Zbilinear30d24 1 QC3.13 [2.26, 4.22]2.33+2.55 [1.49, 3.70]4.01 [2.74, 5.20]29% [15%, 41%]33%62%+0.05+0.302026-08-07 → 2026-08-30
tmin00Zbilinear90d24 1 QC3.13 [2.19, 4.35]2.33+2.55 [1.21, 4.01]4.01 [2.59, 5.32]29% [11%, 43%]33%62%+0.05+0.302026-08-07 → 2026-08-30
tmin00Zbilinear365d24 1 QC3.13 [2.17, 4.46]2.33+2.55 [1.19, 4.01]4.01 [2.54, 5.37]29% [11%, 43%]33%62%+0.05+0.302026-08-07 → 2026-08-30
tmin00Zbilinearall24 1 QC3.13 [2.11, 4.48]2.33+2.55 [1.27, 3.99]4.01 [2.53, 5.31]29% [10%, 43%]33%62%+0.05+0.302026-08-07 → 2026-08-30
tmin00Znearest30d24 1 QC3.22 [2.35, 4.35]2.38+2.67 [1.57, 3.83]4.12 [2.82, 5.29]25% [7%, 40%]33%62%+0.02+0.292026-08-07 → 2026-08-30
tmin00Znearest90d24 1 QC3.22 [2.26, 4.48]2.38+2.67 [1.28, 4.18]4.12 [2.66, 5.44]25% [0%, 40%]33%62%+0.02+0.292026-08-07 → 2026-08-30
tmin00Znearest365d24 1 QC3.22 [2.23, 4.58]2.38+2.67 [1.24, 4.16]4.12 [2.62, 5.50]25% [0%, 41%]33%62%+0.02+0.292026-08-07 → 2026-08-30
tmin00Znearestall24 1 QC3.22 [2.17, 4.62]2.38+2.67 [1.37, 4.12]4.12 [2.63, 5.44]25% [0%, 41%]33%62%+0.02+0.292026-08-07 → 2026-08-30
tmin12Zbilinear30d24 1 QC2.77 [1.76, 3.84]2.42+2.48 [1.38, 3.74]3.86 [2.35, 5.11]33% [20%, 50%]54%58%+0.16+0.272026-08-07 → 2026-08-30
tmin12Zbilinear90d24 1 QC2.77 [1.63, 4.02]2.42+2.48 [1.30, 3.92]3.86 [2.15, 5.29]33% [18%, 50%]54%58%+0.16+0.272026-08-07 → 2026-08-30
tmin12Zbilinear365d24 1 QC2.77 [1.47, 4.09]2.42+2.48 [1.30, 3.88]3.86 [1.95, 5.42]33% [20%, 52%]54%58%+0.16+0.272026-08-07 → 2026-08-30
tmin12Zbilinearall24 1 QC2.77 [1.53, 4.01]2.42+2.48 [1.23, 3.92]3.86 [2.04, 5.42]33% [19%, 53%]54%58%+0.16+0.272026-08-07 → 2026-08-30
tmin12Znearest30d24 1 QC2.84 [1.81, 3.93]2.47+2.60 [1.49, 3.87]3.96 [2.43, 5.21]33% [20%, 50%]54%58%+0.14+0.262026-08-07 → 2026-08-30
tmin12Znearest90d24 1 QC2.84 [1.65, 4.12]2.47+2.60 [1.38, 4.06]3.96 [2.20, 5.41]33% [18%, 50%]54%58%+0.14+0.262026-08-07 → 2026-08-30
tmin12Znearest365d24 1 QC2.84 [1.50, 4.17]2.47+2.60 [1.34, 4.03]3.96 [2.01, 5.51]33% [20%, 52%]54%58%+0.14+0.262026-08-07 → 2026-08-30
tmin12Znearestall24 1 QC2.84 [1.56, 4.13]2.47+2.60 [1.29, 4.07]3.96 [2.12, 5.51]33% [19%, 53%]54%58%+0.14+0.262026-08-07 → 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 KNYC, lead day 6, 00Z bilinear tmax+10+50-5-102026-08-07: -2.48 °F2026-08-08: +2.28 °F2026-08-09: +1.24 °F2026-08-10: +4.24 °F2026-08-11: +0.17 °F2026-08-12: -1.53 °F2026-08-13: -0.92 °F2026-08-14: -0.62 °F2026-08-15: -2.39 °F2026-08-16: -1.51 °F2026-08-17: +3.77 °F2026-08-18: -6.22 °F2026-08-19: -2.93 °F2026-08-20: -2.67 °F2026-08-21: -3.91 °F2026-08-22: +3.51 °F2026-08-23: +1.21 °F2026-08-24: -2.54 °F2026-08-25: -0.52 °F2026-08-26: -0.97 °F2026-08-27: -1.81 °F2026-08-28: -3.21 °F2026-08-29: +2.56 °F2026-08-30: +1.54 °F2026-08-072026-08-30°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 (24 days, newest first) · download CSV
Climatological dayError °F
2026-08-30+1.54
2026-08-29+2.56
2026-08-28-3.21
2026-08-27-1.81
2026-08-26-0.97
2026-08-25-0.52
2026-08-24-2.54
2026-08-23+1.21
2026-08-22+3.51
2026-08-21-3.91
2026-08-20-2.67
2026-08-19-2.93
2026-08-18-6.22
2026-08-17+3.77
2026-08-16-1.51
2026-08-15-2.39
2026-08-14-0.62
2026-08-13-0.92
2026-08-12-1.53
2026-08-11+0.17
2026-08-10+4.24
2026-08-09+1.24
2026-08-08+2.28
2026-08-07-2.48

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KNYC, lead day 6-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 1 day-6 to -5 °F: 0 days-5 to -4 °F: 0 days-4 to -3 °F: 2 days-3 to -2 °F: 5 days-2 to -1 °F: 3 days-1 to 0 °F: 4 days0 to 1 °F: 1 day1 to 2 °F: 3 days2 to 3 °F: 2 days3 to 4 °F: 2 days4 to 5 °F: 1 day5 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| 2.34 · P90 |e| 3.87 °F-100+10 °Fn = 24 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
-7.00-6.001
-6.00-5.000
-5.00-4.000
-4.00-3.002
-3.00-2.005
-2.00-1.003
-1.00+0.004
+0.00+1.001
+1.00+2.003
+2.00+3.002
+3.00+4.002
+4.00+5.001
+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
2026-08242.28 -0.57

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-07 → 2026-08-30 24
ECMWF AIFS Single2026-08-07 → 2026-08-30 24
ECMWF AIFS Single2026-08-07 → 2026-08-30 24
ECMWF AIFS Single2026-08-07 → 2026-08-30 24

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
NCEP GFS 24 -2.16 [-4.45, -0.69] yes
GraphCast (IFS init) 24 -0.10 [-0.93, 0.82] no
ECMWF IFS HRES 19 -1.41 [-2.42, -0.59] yes
Persistence (baseline) 24 -1.39 [-2.50, 0.16] no

Cite this page

ShortCastCheck, KNYC aifs_single lead 6, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KNYC/model/aifs_single/lead/6/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KNYC (New York Central Park), model aifs_single, lead day 6. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KNYC/model/aifs_single/lead/6/

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