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

Philadelphia Intl · Aurora (IFS init) · lead day 1

KPHL · aurora_ifs · 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, AURO_v100, starting 2026-08-28 — 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
tmax00Zbilinear30d2 1 QC4.19 [3.54, 4.84]0.65-4.19 [-4.84, -3.54]4.24 [3.54, 4.84]0% [0%, 0%]0%0%+0.16+0.872026-08-29 → 2026-08-30
tmax00Zbilinear90d2 1 QC4.19 [3.54, 4.84]0.65-4.19 [-4.84, -3.54]4.24 [3.54, 4.84]0% [0%, 0%]0%0%+0.16+0.872026-08-29 → 2026-08-30
tmax00Zbilinear365d2 1 QC4.19 [3.54, 4.84]0.65-4.19 [-4.84, -3.54]4.24 [3.54, 4.84]0% [0%, 0%]0%0%+0.16+0.872026-08-29 → 2026-08-30
tmax00Zbilinearall2 1 QC4.19 [3.54, 4.84]0.65-4.19 [-4.84, -3.54]4.24 [3.54, 4.84]0% [0%, 0%]0%0%+0.16+0.872026-08-29 → 2026-08-30
tmax00Znearest30d2 1 QC3.69 [3.18, 4.21]0.51-3.69 [-4.21, -3.18]3.73 [3.18, 4.21]0% [0%, 0%]0%0%+0.26+0.902026-08-29 → 2026-08-30
tmax00Znearest90d2 1 QC3.69 [3.18, 4.21]0.51-3.69 [-4.21, -3.18]3.73 [3.18, 4.21]0% [0%, 0%]0%0%+0.26+0.902026-08-29 → 2026-08-30
tmax00Znearest365d2 1 QC3.69 [3.18, 4.21]0.51-3.69 [-4.21, -3.18]3.73 [3.18, 4.21]0% [0%, 0%]0%0%+0.26+0.902026-08-29 → 2026-08-30
tmax00Znearestall2 1 QC3.69 [3.18, 4.21]0.51-3.69 [-4.21, -3.18]3.73 [3.18, 4.21]0% [0%, 0%]0%0%+0.26+0.902026-08-29 → 2026-08-30
tmax12Zbilinear30d2 1 QC5.17 [4.85, 5.49]0.32-5.17 [-5.49, -4.85]5.18 [4.85, 5.49]0% [0%, 0%]0%0%-0.03+0.942026-08-29 → 2026-08-30
tmax12Zbilinear90d2 1 QC5.17 [4.85, 5.49]0.32-5.17 [-5.49, -4.85]5.18 [4.85, 5.49]0% [0%, 0%]0%0%-0.03+0.942026-08-29 → 2026-08-30
tmax12Zbilinear365d2 1 QC5.17 [4.85, 5.49]0.32-5.17 [-5.49, -4.85]5.18 [4.85, 5.49]0% [0%, 0%]0%0%-0.03+0.942026-08-29 → 2026-08-30
tmax12Zbilinearall2 1 QC5.17 [4.85, 5.49]0.32-5.17 [-5.49, -4.85]5.18 [4.85, 5.49]0% [0%, 0%]0%0%-0.03+0.942026-08-29 → 2026-08-30
tmax12Znearest30d2 1 QC4.65 [4.47, 4.83]0.18-4.65 [-4.83, -4.47]4.65 [4.47, 4.83]0% [0%, 0%]0%0%+0.07+0.962026-08-29 → 2026-08-30
tmax12Znearest90d2 1 QC4.65 [4.47, 4.83]0.18-4.65 [-4.83, -4.47]4.65 [4.47, 4.83]0% [0%, 0%]0%0%+0.07+0.962026-08-29 → 2026-08-30
tmax12Znearest365d2 1 QC4.65 [4.47, 4.83]0.18-4.65 [-4.83, -4.47]4.65 [4.47, 4.83]0% [0%, 0%]0%0%+0.07+0.962026-08-29 → 2026-08-30
tmax12Znearestall2 1 QC4.65 [4.47, 4.83]0.18-4.65 [-4.83, -4.47]4.65 [4.47, 4.83]0% [0%, 0%]0%0%+0.07+0.962026-08-29 → 2026-08-30
tmin00Zbilinear30d2 1 QC0.41 [0.01, 0.80]0.39-0.41 [-0.80, -0.01]0.57 [0.01, 0.80]100% [100%, 100%]100%100%+0.86+0.872026-08-29 → 2026-08-30
tmin00Zbilinear90d2 1 QC0.41 [0.01, 0.80]0.39-0.41 [-0.80, -0.01]0.57 [0.01, 0.80]100% [100%, 100%]100%100%+0.86+0.872026-08-29 → 2026-08-30
tmin00Zbilinear365d2 1 QC0.41 [0.01, 0.80]0.39-0.41 [-0.80, -0.01]0.57 [0.01, 0.80]100% [100%, 100%]100%100%+0.86+0.872026-08-29 → 2026-08-30
tmin00Zbilinearall2 1 QC0.41 [0.01, 0.80]0.39-0.41 [-0.80, -0.01]0.57 [0.01, 0.80]100% [100%, 100%]100%100%+0.86+0.872026-08-29 → 2026-08-30
tmin00Znearest30d2 1 QC0.44 [0.15, 0.73]0.44+0.29 [-0.15, 0.73]0.53 [0.15, 0.73]100% [100%, 100%]100%100%+0.85+0.852026-08-29 → 2026-08-30
tmin00Znearest90d2 1 QC0.44 [0.15, 0.73]0.44+0.29 [-0.15, 0.73]0.53 [0.15, 0.73]100% [100%, 100%]100%100%+0.85+0.852026-08-29 → 2026-08-30
tmin00Znearest365d2 1 QC0.44 [0.15, 0.73]0.44+0.29 [-0.15, 0.73]0.53 [0.15, 0.73]100% [100%, 100%]100%100%+0.85+0.852026-08-29 → 2026-08-30
tmin00Znearestall2 1 QC0.44 [0.15, 0.73]0.44+0.29 [-0.15, 0.73]0.53 [0.15, 0.73]100% [100%, 100%]100%100%+0.85+0.852026-08-29 → 2026-08-30
tmin12Zbilinear30d2 1 QC1.54 [1.17, 1.91]0.37-1.54 [-1.91, -1.17]1.59 [1.17, 1.91]0% [0%, 0%]100%100%+0.49+0.882026-08-29 → 2026-08-30
tmin12Zbilinear90d2 1 QC1.54 [1.17, 1.91]0.37-1.54 [-1.91, -1.17]1.59 [1.17, 1.91]0% [0%, 0%]100%100%+0.49+0.882026-08-29 → 2026-08-30
tmin12Zbilinear365d2 1 QC1.54 [1.17, 1.91]0.37-1.54 [-1.91, -1.17]1.59 [1.17, 1.91]0% [0%, 0%]100%100%+0.49+0.882026-08-29 → 2026-08-30
tmin12Zbilinearall2 1 QC1.54 [1.17, 1.91]0.37-1.54 [-1.91, -1.17]1.59 [1.17, 1.91]0% [0%, 0%]100%100%+0.49+0.882026-08-29 → 2026-08-30
tmin12Znearest30d2 1 QC0.91 [0.49, 1.33]0.42-0.91 [-1.33, -0.49]1.01 [0.49, 1.33]50% [0%, 100%]100%100%+0.70+0.862026-08-29 → 2026-08-30
tmin12Znearest90d2 1 QC0.91 [0.49, 1.33]0.42-0.91 [-1.33, -0.49]1.01 [0.49, 1.33]50% [0%, 100%]100%100%+0.70+0.862026-08-29 → 2026-08-30
tmin12Znearest365d2 1 QC0.91 [0.49, 1.33]0.42-0.91 [-1.33, -0.49]1.01 [0.49, 1.33]50% [0%, 100%]100%100%+0.70+0.862026-08-29 → 2026-08-30
tmin12Znearestall2 1 QC0.91 [0.49, 1.33]0.42-0.91 [-1.33, -0.49]1.01 [0.49, 1.33]50% [0%, 100%]100%100%+0.70+0.862026-08-29 → 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 Aurora (IFS init) at KPHL, lead day 1, 00Z bilinear tmax+5+2.50-2.5-52026-08-29: -3.54 °F2026-08-30: -4.84 °F2026-08-292026-08-30°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 (2 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-4.84
2026-08-29-3.54

Error distribution

Distribution of the signed daily error in °F for Aurora (IFS init) at KPHL, lead day 1-5 to -4.5 °F: 1 day-4.5 to -4 °F: 0 days-4 to -3.5 °F: 1 day-3.5 to -3 °F: 0 days-3 to -2.5 °F: 0 days-2.5 to -2 °F: 0 days-2 to -1.5 °F: 0 days-1.5 to -1 °F: 0 days-1 to -0.5 °F: 0 days-0.5 to 0 °F: 0 days0 to 0.5 °F: 0 days0.5 to 1 °F: 0 days1 to 1.5 °F: 0 days1.5 to 2 °F: 0 days2 to 2.5 °F: 0 days2.5 to 3 °F: 0 days3 to 3.5 °F: 0 days3.5 to 4 °F: 0 days4 to 4.5 °F: 0 days4.5 to 5 °F: 0 daysdashed: P50 |e| 4.19 · P90 |e| 4.71 °F-50+5 °Fn = 2 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
-5.00-4.501
-4.50-4.000
-4.00-3.501
-3.50-3.000
-3.00-2.500
-2.50-2.000
-2.00-1.500
-1.50-1.000
-1.00-0.500
-0.50+0.000
+0.00+0.500
+0.50+1.000
+1.00+1.500
+1.50+2.000
+2.00+2.500
+2.50+3.000
+3.00+3.500
+3.50+4.000
+4.00+4.500
+4.50+5.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-0824.19 -4.19

Availability

ModelScored period DaysCoverage
Aurora (IFS init)2026-08-29 → 2026-08-30 2
Aurora (IFS init)2026-08-29 → 2026-08-30 2
Aurora (IFS init)2026-08-29 → 2026-08-30 2
Aurora (IFS init)2026-08-29 → 2026-08-30 2

Compared with other models

Paired bootstrap on the days both models cover (90d, 00Z, bilinear, daily maximum). Negative means Aurora (IFS init) has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 2 +1.25 [0.59, 1.92] yes
Aurora (GFS init) 1 -1.68 [-1.68, -1.68] yes
FourCastNet v2 (GFS init) 1 +0.12 [0.12, 0.12] yes
FourCastNet v2 (IFS init) 2 +1.48 [-0.41, 3.37] no
NCEP GFS 2 +4.10 [3.45, 4.76] yes
GraphCast (GFS init) 1 -1.51 [-1.51, -1.51] yes
GraphCast (IFS init) 2 -0.96 [-1.25, -0.67] yes
ECMWF IFS HRES 2 +0.41 [-0.86, 1.68] no
Pangu-Weather (GFS init) 1 +2.30 [2.30, 2.30] yes
Pangu-Weather (IFS init) 2 +2.53 [1.53, 3.53] yes
Persistence (baseline) 2 -0.81 [-1.46, -0.16] yes

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KPHL (Philadelphia Intl), model aurora_ifs, 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/KPHL/model/aurora_ifs/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