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CastCheck methodology v0.2 · data through 2026-08-30

New York Central Park · ECMWF AIFS Single · lead day 8

KNYC · aifs_single · lead 8

Target day = initialization date + 8 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
tmax00Zbilinear30d22 1 QC2.34 [1.78, 2.76]1.81-1.83 [-2.40, -1.05]2.86 [2.05, 3.36]23% [11%, 35%]45%73%+0.31+0.462026-08-09 → 2026-08-30
tmax00Zbilinear90d22 1 QC2.34 [1.64, 2.76]1.81-1.83 [-2.45, -0.98]2.86 [1.91, 3.36]23% [10%, 38%]45%73%+0.31+0.462026-08-09 → 2026-08-30
tmax00Zbilinear365d22 1 QC2.34 [1.60, 2.80]1.81-1.83 [-2.49, -0.87]2.86 [1.89, 3.42]23% [7%, 38%]45%73%+0.31+0.462026-08-09 → 2026-08-30
tmax00Zbilinearall22 1 QC2.34 [1.61, 2.79]1.81-1.83 [-2.49, -0.99]2.86 [1.90, 3.41]23% [8%, 40%]45%73%+0.31+0.462026-08-09 → 2026-08-30
tmax00Znearest30d22 1 QC2.15 [1.61, 2.57]1.83-1.44 [-2.01, -0.69]2.66 [1.90, 3.15]27% [11%, 42%]45%77%+0.37+0.452026-08-09 → 2026-08-30
tmax00Znearest90d22 1 QC2.15 [1.50, 2.58]1.83-1.44 [-2.06, -0.53]2.66 [1.74, 3.16]27% [7%, 43%]45%77%+0.37+0.452026-08-09 → 2026-08-30
tmax00Znearest365d22 1 QC2.15 [1.45, 2.59]1.83-1.44 [-2.10, -0.46]2.66 [1.74, 3.21]27% [7%, 43%]45%77%+0.37+0.452026-08-09 → 2026-08-30
tmax00Znearestall22 1 QC2.15 [1.53, 2.59]1.83-1.44 [-2.11, -0.55]2.66 [1.76, 3.21]27% [8%, 44%]45%77%+0.37+0.452026-08-09 → 2026-08-30
tmax12Zbilinear30d22 1 QC2.12 [1.68, 2.56]1.54-1.66 [-2.32, -0.92]2.61 [2.13, 3.03]27% [15%, 39%]50%77%+0.38+0.532026-08-09 → 2026-08-30
tmax12Zbilinear90d22 1 QC2.12 [1.71, 2.58]1.54-1.66 [-2.35, -0.79]2.61 [2.09, 3.03]27% [14%, 41%]50%77%+0.38+0.532026-08-09 → 2026-08-30
tmax12Zbilinear365d22 1 QC2.12 [1.62, 2.59]1.54-1.66 [-2.37, -0.79]2.61 [2.00, 3.02]27% [14%, 43%]50%77%+0.38+0.532026-08-09 → 2026-08-30
tmax12Zbilinearall22 1 QC2.12 [1.65, 2.61]1.54-1.66 [-2.45, -0.86]2.61 [2.00, 3.03]27% [14%, 40%]50%77%+0.38+0.532026-08-09 → 2026-08-30
tmax12Znearest30d22 1 QC1.92 [1.56, 2.30]1.59-1.26 [-1.94, -0.47]2.43 [1.97, 2.84]32% [19%, 43%]59%77%+0.44+0.522026-08-09 → 2026-08-30
tmax12Znearest90d22 1 QC1.92 [1.61, 2.31]1.59-1.26 [-1.98, -0.29]2.43 [1.98, 2.83]32% [18%, 43%]59%77%+0.44+0.522026-08-09 → 2026-08-30
tmax12Znearest365d22 1 QC1.92 [1.54, 2.31]1.59-1.26 [-1.99, -0.26]2.43 [1.89, 2.81]32% [18%, 43%]59%77%+0.44+0.522026-08-09 → 2026-08-30
tmax12Znearestall22 1 QC1.92 [1.53, 2.32]1.59-1.26 [-2.07, -0.41]2.43 [1.86, 2.85]32% [17%, 44%]59%77%+0.44+0.522026-08-09 → 2026-08-30
tmin00Zbilinear30d22 1 QC2.62 [1.53, 3.79]1.88+2.24 [0.52, 3.64]3.44 [1.83, 4.65]18% [5%, 33%]45%68%+0.23+0.402026-08-09 → 2026-08-30
tmin00Zbilinear90d22 1 QC2.62 [1.41, 3.87]1.88+2.24 [0.08, 3.75]3.44 [1.62, 4.70]18% [0%, 33%]45%68%+0.23+0.402026-08-09 → 2026-08-30
tmin00Zbilinear365d22 1 QC2.62 [1.32, 4.05]1.88+2.24 [0.08, 4.00]3.44 [1.53, 4.82]18% [0%, 33%]45%68%+0.23+0.402026-08-09 → 2026-08-30
tmin00Zbilinearall22 1 QC2.62 [1.42, 3.79]1.88+2.24 [-0.06, 3.70]3.44 [1.61, 4.65]18% [0%, 35%]45%68%+0.23+0.402026-08-09 → 2026-08-30
tmin00Znearest30d22 1 QC2.75 [1.62, 3.94]1.92+2.36 [0.58, 3.78]3.55 [1.92, 4.76]18% [5%, 33%]45%68%+0.19+0.392026-08-09 → 2026-08-30
tmin00Znearest90d22 1 QC2.75 [1.50, 4.01]1.92+2.36 [0.11, 3.90]3.55 [1.68, 4.82]18% [0%, 33%]45%68%+0.19+0.392026-08-09 → 2026-08-30
tmin00Znearest365d22 1 QC2.75 [1.38, 4.21]1.92+2.36 [0.12, 4.15]3.55 [1.62, 4.94]18% [0%, 33%]45%68%+0.19+0.392026-08-09 → 2026-08-30
tmin00Znearestall22 1 QC2.75 [1.49, 3.95]1.92+2.36 [-0.03, 3.85]3.55 [1.67, 4.76]18% [0%, 35%]45%68%+0.19+0.392026-08-09 → 2026-08-30
tmin12Zbilinear30d22 1 QC2.90 [2.22, 3.85]1.67+2.61 [1.34, 3.75]3.55 [2.47, 4.62]14% [0%, 25%]32%59%+0.15+0.472026-08-09 → 2026-08-30
tmin12Zbilinear90d22 1 QC2.90 [2.20, 3.90]1.67+2.61 [1.05, 3.86]3.55 [2.42, 4.68]14% [0%, 26%]32%59%+0.15+0.472026-08-09 → 2026-08-30
tmin12Zbilinear365d22 1 QC2.90 [2.19, 3.99]1.67+2.61 [1.12, 3.91]3.55 [2.39, 4.75]14% [0%, 27%]32%59%+0.15+0.472026-08-09 → 2026-08-30
tmin12Zbilinearall22 1 QC2.90 [2.20, 3.85]1.67+2.61 [0.82, 3.73]3.55 [2.43, 4.65]14% [0%, 26%]32%59%+0.15+0.472026-08-09 → 2026-08-30
tmin12Znearest30d22 1 QC3.05 [2.34, 3.98]1.70+2.75 [1.44, 3.91]3.67 [2.56, 4.74]14% [0%, 25%]32%55%+0.11+0.462026-08-09 → 2026-08-30
tmin12Znearest90d22 1 QC3.05 [2.31, 4.06]1.70+2.75 [1.13, 4.03]3.67 [2.50, 4.80]14% [0%, 26%]32%55%+0.11+0.462026-08-09 → 2026-08-30
tmin12Znearest365d22 1 QC3.05 [2.30, 4.16]1.70+2.75 [1.20, 4.06]3.67 [2.45, 4.88]14% [0%, 27%]32%55%+0.11+0.462026-08-09 → 2026-08-30
tmin12Znearestall22 1 QC3.05 [2.33, 4.01]1.70+2.75 [0.89, 3.88]3.67 [2.50, 4.75]14% [0%, 26%]32%55%+0.11+0.462026-08-09 → 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 8, 00Z bilinear tmax+10+50-5-102026-08-09: -2.6 °F2026-08-10: +0.64 °F2026-08-11: -1.06 °F2026-08-12: -6.29 °F2026-08-13: -0.35 °F2026-08-14: -5.28 °F2026-08-15: -3.2 °F2026-08-16: -1.61 °F2026-08-17: +0.35 °F2026-08-18: -2.49 °F2026-08-19: -1.04 °F2026-08-20: -0.55 °F2026-08-21: -2.69 °F2026-08-22: +2.83 °F2026-08-23: -1.24 °F2026-08-24: -4.66 °F2026-08-25: -4.38 °F2026-08-26: -3.03 °F2026-08-27: +1.38 °F2026-08-28: -2.71 °F2026-08-29: -2.64 °F2026-08-30: +0.46 °F2026-08-092026-08-30°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 (22 days, newest first) · download CSV
Climatological dayError °F
2026-08-30+0.46
2026-08-29-2.64
2026-08-28-2.71
2026-08-27+1.38
2026-08-26-3.03
2026-08-25-4.38
2026-08-24-4.66
2026-08-23-1.24
2026-08-22+2.83
2026-08-21-2.69
2026-08-20-0.55
2026-08-19-1.04
2026-08-18-2.49
2026-08-17+0.35
2026-08-16-1.61
2026-08-15-3.20
2026-08-14-5.28
2026-08-13-0.35
2026-08-12-6.29
2026-08-11-1.06
2026-08-10+0.64
2026-08-09-2.60

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KNYC, lead day 8-10 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: 1 day-5 to -4 °F: 2 days-4 to -3 °F: 2 days-3 to -2 °F: 5 days-2 to -1 °F: 4 days-1 to 0 °F: 2 days0 to 1 °F: 3 days1 to 2 °F: 1 day2 to 3 °F: 1 day3 to 4 °F: 0 days4 to 5 °F: 0 days5 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| 2.55 · P90 |e| 4.63 °F-100+10 °Fn = 22 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
-6.00-5.001
-5.00-4.002
-4.00-3.002
-3.00-2.005
-2.00-1.004
-1.00+0.002
+0.00+1.003
+1.00+2.001
+2.00+3.001
+3.00+4.000
+4.00+5.000
+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
2026-08222.34 -1.83

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22

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 22 -1.33 [-3.15, -0.27] yes
GraphCast (IFS init) 22 -1.18 [-2.45, 0.09] no
ECMWF IFS HRES 17 -1.20 [-3.24, 0.84] no
Persistence (baseline) 22 -1.07 [-2.01, -0.10] yes

Cite this page

ShortCastCheck, KNYC aifs_single lead 8, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KNYC/model/aifs_single/lead/8/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KNYC (New York Central Park), model aifs_single, lead day 8. 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/8/

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