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

All stations (mean of daily station errors) · Aurora (IFS init) · lead day 2

ALL · aurora_ifs · lead 2

Target day = initialization date + 2 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, 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
tmax00Zbilinear30d1 1 QC5.03 [5.03, 5.03]0.00-4.86 [-4.86, -4.86]5.68 [5.68, 5.68]9% [9%, 9%]17%22%-0.50—2026-08-30 → 2026-08-30
tmax00Zbilinear90d1 1 QC5.03 [5.03, 5.03]0.00-4.86 [-4.86, -4.86]5.68 [5.68, 5.68]9% [9%, 9%]17%22%-0.50—2026-08-30 → 2026-08-30
tmax00Zbilinear365d1 1 QC5.03 [5.03, 5.03]0.00-4.86 [-4.86, -4.86]5.68 [5.68, 5.68]9% [9%, 9%]17%22%-0.50—2026-08-30 → 2026-08-30
tmax00Zbilinearall1 1 QC5.03 [5.03, 5.03]0.00-4.86 [-4.86, -4.86]5.68 [5.68, 5.68]9% [9%, 9%]17%22%-0.50—2026-08-30 → 2026-08-30
tmax00Znearest30d1 1 QC4.93 [4.93, 4.93]0.00-4.71 [-4.71, -4.71]5.62 [5.62, 5.62]9% [9%, 9%]22%26%-0.47—2026-08-30 → 2026-08-30
tmax00Znearest90d1 1 QC4.93 [4.93, 4.93]0.00-4.71 [-4.71, -4.71]5.62 [5.62, 5.62]9% [9%, 9%]22%26%-0.47—2026-08-30 → 2026-08-30
tmax00Znearest365d1 1 QC4.93 [4.93, 4.93]0.00-4.71 [-4.71, -4.71]5.62 [5.62, 5.62]9% [9%, 9%]22%26%-0.47—2026-08-30 → 2026-08-30
tmax00Znearestall1 1 QC4.93 [4.93, 4.93]0.00-4.71 [-4.71, -4.71]5.62 [5.62, 5.62]9% [9%, 9%]22%26%-0.47—2026-08-30 → 2026-08-30
tmax12Zbilinear30d1 1 QC5.26 [5.26, 5.26]0.00-5.22 [-5.22, -5.22]5.85 [5.85, 5.85]4% [4%, 4%]17%22%-0.56—2026-08-30 → 2026-08-30
tmax12Zbilinear90d1 1 QC5.26 [5.26, 5.26]0.00-5.22 [-5.22, -5.22]5.85 [5.85, 5.85]4% [4%, 4%]17%22%-0.56—2026-08-30 → 2026-08-30
tmax12Zbilinear365d1 1 QC5.26 [5.26, 5.26]0.00-5.22 [-5.22, -5.22]5.85 [5.85, 5.85]4% [4%, 4%]17%22%-0.56—2026-08-30 → 2026-08-30
tmax12Zbilinearall1 1 QC5.26 [5.26, 5.26]0.00-5.22 [-5.22, -5.22]5.85 [5.85, 5.85]4% [4%, 4%]17%22%-0.56—2026-08-30 → 2026-08-30
tmax12Znearest30d1 1 QC5.12 [5.12, 5.12]0.00-5.06 [-5.06, -5.06]5.78 [5.78, 5.78]9% [9%, 9%]22%26%-0.52—2026-08-30 → 2026-08-30
tmax12Znearest90d1 1 QC5.12 [5.12, 5.12]0.00-5.06 [-5.06, -5.06]5.78 [5.78, 5.78]9% [9%, 9%]22%26%-0.52—2026-08-30 → 2026-08-30
tmax12Znearest365d1 1 QC5.12 [5.12, 5.12]0.00-5.06 [-5.06, -5.06]5.78 [5.78, 5.78]9% [9%, 9%]22%26%-0.52—2026-08-30 → 2026-08-30
tmax12Znearestall1 1 QC5.12 [5.12, 5.12]0.00-5.06 [-5.06, -5.06]5.78 [5.78, 5.78]9% [9%, 9%]22%26%-0.52—2026-08-30 → 2026-08-30
tmin00Zbilinear30d1 1 QC2.55 [2.55, 2.55]0.00-0.80 [-0.80, -0.80]3.20 [3.20, 3.20]26% [26%, 26%]48%70%+0.22—2026-08-30 → 2026-08-30
tmin00Zbilinear90d1 1 QC2.55 [2.55, 2.55]0.00-0.80 [-0.80, -0.80]3.20 [3.20, 3.20]26% [26%, 26%]48%70%+0.22—2026-08-30 → 2026-08-30
tmin00Zbilinear365d1 1 QC2.55 [2.55, 2.55]0.00-0.80 [-0.80, -0.80]3.20 [3.20, 3.20]26% [26%, 26%]48%70%+0.22—2026-08-30 → 2026-08-30
tmin00Zbilinearall1 1 QC2.55 [2.55, 2.55]0.00-0.80 [-0.80, -0.80]3.20 [3.20, 3.20]26% [26%, 26%]48%70%+0.22—2026-08-30 → 2026-08-30
tmin00Znearest30d1 1 QC2.51 [2.51, 2.51]0.00-0.84 [-0.84, -0.84]3.27 [3.27, 3.27]30% [30%, 30%]48%70%+0.23—2026-08-30 → 2026-08-30
tmin00Znearest90d1 1 QC2.51 [2.51, 2.51]0.00-0.84 [-0.84, -0.84]3.27 [3.27, 3.27]30% [30%, 30%]48%70%+0.23—2026-08-30 → 2026-08-30
tmin00Znearest365d1 1 QC2.51 [2.51, 2.51]0.00-0.84 [-0.84, -0.84]3.27 [3.27, 3.27]30% [30%, 30%]48%70%+0.23—2026-08-30 → 2026-08-30
tmin00Znearestall1 1 QC2.51 [2.51, 2.51]0.00-0.84 [-0.84, -0.84]3.27 [3.27, 3.27]30% [30%, 30%]48%70%+0.23—2026-08-30 → 2026-08-30
tmin12Zbilinear30d1 1 QC2.48 [2.48, 2.48]0.00-1.07 [-1.07, -1.07]3.09 [3.09, 3.09]26% [26%, 26%]48%65%+0.24—2026-08-30 → 2026-08-30
tmin12Zbilinear90d1 1 QC2.48 [2.48, 2.48]0.00-1.07 [-1.07, -1.07]3.09 [3.09, 3.09]26% [26%, 26%]48%65%+0.24—2026-08-30 → 2026-08-30
tmin12Zbilinear365d1 1 QC2.48 [2.48, 2.48]0.00-1.07 [-1.07, -1.07]3.09 [3.09, 3.09]26% [26%, 26%]48%65%+0.24—2026-08-30 → 2026-08-30
tmin12Zbilinearall1 1 QC2.48 [2.48, 2.48]0.00-1.07 [-1.07, -1.07]3.09 [3.09, 3.09]26% [26%, 26%]48%65%+0.24—2026-08-30 → 2026-08-30
tmin12Znearest30d1 1 QC2.45 [2.45, 2.45]0.00-1.10 [-1.10, -1.10]3.16 [3.16, 3.16]30% [30%, 30%]39%65%+0.25—2026-08-30 → 2026-08-30
tmin12Znearest90d1 1 QC2.45 [2.45, 2.45]0.00-1.10 [-1.10, -1.10]3.16 [3.16, 3.16]30% [30%, 30%]39%65%+0.25—2026-08-30 → 2026-08-30
tmin12Znearest365d1 1 QC2.45 [2.45, 2.45]0.00-1.10 [-1.10, -1.10]3.16 [3.16, 3.16]30% [30%, 30%]39%65%+0.25—2026-08-30 → 2026-08-30
tmin12Znearestall1 1 QC2.45 [2.45, 2.45]0.00-1.10 [-1.10, -1.10]3.16 [3.16, 3.16]30% [30%, 30%]39%65%+0.25—2026-08-30 → 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 ALL, lead day 2, 00Z bilinear tmax+5+2.50-2.5-52026-08-30: -4.86 °F2026-08-30°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 (1 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-4.86

Error distribution

Distribution of the signed daily error in °F for Aurora (IFS init) at ALL, lead day 2-5 to -4.5 °F: 1 day-4.5 to -4 °F: 0 days-4 to -3.5 °F: 0 days-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| 4.86 · P90 |e| 4.86 °F-50+5 °Fn = 1 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
-4.00-3.500
-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
2026-0814.86 -4.86

Availability

ModelScored period DaysCoverage
Aurora (IFS init)2026-08-30 → 2026-08-30 1
Aurora (IFS init)2026-08-30 → 2026-08-30 1
Aurora (IFS init)2026-08-30 → 2026-08-30 1
Aurora (IFS init)2026-08-30 → 2026-08-30 1

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 1 +1.88 [1.88, 1.88] yes
FourCastNet v2 (IFS init) 1 +1.36 [1.36, 1.36] yes
NCEP GFS 1 +1.89 [1.89, 1.89] yes
GraphCast (IFS init) 1 -0.08 [-0.08, -0.08] yes
ECMWF IFS HRES 1 +1.75 [1.75, 1.75] yes
Pangu-Weather (IFS init) 1 +0.98 [0.98, 0.98] yes
Persistence (baseline) 1 +1.67 [1.67, 1.67] yes

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: ALL (All stations (mean of daily station errors)), model aurora_ifs, lead day 2. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/ALL/model/aurora_ifs/lead/2/

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