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

All stations (mean of daily station errors) · Aurora (GFS init) · lead day 1

ALL · aurora_gfs · 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, 2 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 QC6.29 [6.29, 6.29]0.00-6.29 [-6.29, -6.29]6.84 [6.84, 6.84]4% [4%, 4%]4%13%-0.98—2026-08-30 → 2026-08-30
tmax00Zbilinear90d1 1 QC6.29 [6.29, 6.29]0.00-6.29 [-6.29, -6.29]6.84 [6.84, 6.84]4% [4%, 4%]4%13%-0.98—2026-08-30 → 2026-08-30
tmax00Zbilinear365d1 1 QC6.29 [6.29, 6.29]0.00-6.29 [-6.29, -6.29]6.84 [6.84, 6.84]4% [4%, 4%]4%13%-0.98—2026-08-30 → 2026-08-30
tmax00Zbilinearall1 1 QC6.29 [6.29, 6.29]0.00-6.29 [-6.29, -6.29]6.84 [6.84, 6.84]4% [4%, 4%]4%13%-0.98—2026-08-30 → 2026-08-30
tmax00Znearest30d1 1 QC6.15 [6.15, 6.15]0.00-6.10 [-6.10, -6.10]6.81 [6.81, 6.81]9% [9%, 9%]9%17%-0.94—2026-08-30 → 2026-08-30
tmax00Znearest90d1 1 QC6.15 [6.15, 6.15]0.00-6.10 [-6.10, -6.10]6.81 [6.81, 6.81]9% [9%, 9%]9%17%-0.94—2026-08-30 → 2026-08-30
tmax00Znearest365d1 1 QC6.15 [6.15, 6.15]0.00-6.10 [-6.10, -6.10]6.81 [6.81, 6.81]9% [9%, 9%]9%17%-0.94—2026-08-30 → 2026-08-30
tmax00Znearestall1 1 QC6.15 [6.15, 6.15]0.00-6.10 [-6.10, -6.10]6.81 [6.81, 6.81]9% [9%, 9%]9%17%-0.94—2026-08-30 → 2026-08-30
tmax12Zbilinear30d2 2 QC6.53 [6.26, 6.79]0.27-6.53 [-6.79, -6.26]7.02 [6.65, 7.37]0% [0%, 0%]7%11%-1.11+0.602026-08-29 → 2026-08-30
tmax12Zbilinear90d2 2 QC6.53 [6.26, 6.79]0.27-6.53 [-6.79, -6.26]7.02 [6.65, 7.37]0% [0%, 0%]7%11%-1.11+0.602026-08-29 → 2026-08-30
tmax12Zbilinear365d2 2 QC6.53 [6.26, 6.79]0.27-6.53 [-6.79, -6.26]7.02 [6.65, 7.37]0% [0%, 0%]7%11%-1.11+0.602026-08-29 → 2026-08-30
tmax12Zbilinearall2 2 QC6.53 [6.26, 6.79]0.27-6.53 [-6.79, -6.26]7.02 [6.65, 7.37]0% [0%, 0%]7%11%-1.11+0.602026-08-29 → 2026-08-30
tmax12Znearest30d2 2 QC6.42 [6.12, 6.72]0.32-6.40 [-6.72, -6.08]7.04 [6.65, 7.42]7% [4%, 9%]11%15%-1.08+0.522026-08-29 → 2026-08-30
tmax12Znearest90d2 2 QC6.42 [6.12, 6.72]0.32-6.40 [-6.72, -6.08]7.04 [6.65, 7.42]7% [4%, 9%]11%15%-1.08+0.522026-08-29 → 2026-08-30
tmax12Znearest365d2 2 QC6.42 [6.12, 6.72]0.32-6.40 [-6.72, -6.08]7.04 [6.65, 7.42]7% [4%, 9%]11%15%-1.08+0.522026-08-29 → 2026-08-30
tmax12Znearestall2 2 QC6.42 [6.12, 6.72]0.32-6.40 [-6.72, -6.08]7.04 [6.65, 7.42]7% [4%, 9%]11%15%-1.08+0.522026-08-29 → 2026-08-30
tmin00Zbilinear30d1 1 QC2.77 [2.77, 2.77]0.00-0.49 [-0.49, -0.49]3.55 [3.55, 3.55]30% [30%, 30%]39%65%-0.33—2026-08-30 → 2026-08-30
tmin00Zbilinear90d1 1 QC2.77 [2.77, 2.77]0.00-0.49 [-0.49, -0.49]3.55 [3.55, 3.55]30% [30%, 30%]39%65%-0.33—2026-08-30 → 2026-08-30
tmin00Zbilinear365d1 1 QC2.77 [2.77, 2.77]0.00-0.49 [-0.49, -0.49]3.55 [3.55, 3.55]30% [30%, 30%]39%65%-0.33—2026-08-30 → 2026-08-30
tmin00Zbilinearall1 1 QC2.77 [2.77, 2.77]0.00-0.49 [-0.49, -0.49]3.55 [3.55, 3.55]30% [30%, 30%]39%65%-0.33—2026-08-30 → 2026-08-30
tmin00Znearest30d1 1 QC2.72 [2.72, 2.72]0.00-0.50 [-0.50, -0.50]3.62 [3.62, 3.62]35% [35%, 35%]43%70%-0.30—2026-08-30 → 2026-08-30
tmin00Znearest90d1 1 QC2.72 [2.72, 2.72]0.00-0.50 [-0.50, -0.50]3.62 [3.62, 3.62]35% [35%, 35%]43%70%-0.30—2026-08-30 → 2026-08-30
tmin00Znearest365d1 1 QC2.72 [2.72, 2.72]0.00-0.50 [-0.50, -0.50]3.62 [3.62, 3.62]35% [35%, 35%]43%70%-0.30—2026-08-30 → 2026-08-30
tmin00Znearestall1 1 QC2.72 [2.72, 2.72]0.00-0.50 [-0.50, -0.50]3.62 [3.62, 3.62]35% [35%, 35%]43%70%-0.30—2026-08-30 → 2026-08-30
tmin12Zbilinear30d2 2 QC2.69 [2.60, 2.78]0.81+0.25 [-0.55, 1.06]3.44 [3.32, 3.56]26% [26%, 26%]57%63%-0.04+0.502026-08-29 → 2026-08-30
tmin12Zbilinear90d2 2 QC2.69 [2.60, 2.78]0.81+0.25 [-0.55, 1.06]3.44 [3.32, 3.56]26% [26%, 26%]57%63%-0.04+0.502026-08-29 → 2026-08-30
tmin12Zbilinear365d2 2 QC2.69 [2.60, 2.78]0.81+0.25 [-0.55, 1.06]3.44 [3.32, 3.56]26% [26%, 26%]57%63%-0.04+0.502026-08-29 → 2026-08-30
tmin12Zbilinearall2 2 QC2.69 [2.60, 2.78]0.81+0.25 [-0.55, 1.06]3.44 [3.32, 3.56]26% [26%, 26%]57%63%-0.04+0.502026-08-29 → 2026-08-30
tmin12Znearest30d2 2 QC2.69 [2.65, 2.73]0.81+0.27 [-0.54, 1.08]3.53 [3.45, 3.60]28% [22%, 35%]54%63%-0.04+0.492026-08-29 → 2026-08-30
tmin12Znearest90d2 2 QC2.69 [2.65, 2.73]0.81+0.27 [-0.54, 1.08]3.53 [3.45, 3.60]28% [22%, 35%]54%63%-0.04+0.492026-08-29 → 2026-08-30
tmin12Znearest365d2 2 QC2.69 [2.65, 2.73]0.81+0.27 [-0.54, 1.08]3.53 [3.45, 3.60]28% [22%, 35%]54%63%-0.04+0.492026-08-29 → 2026-08-30
tmin12Znearestall2 2 QC2.69 [2.65, 2.73]0.81+0.27 [-0.54, 1.08]3.53 [3.45, 3.60]28% [22%, 35%]54%63%-0.04+0.492026-08-29 → 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 (GFS init) at ALL, lead day 1, 00Z bilinear tmax+10+50-5-102026-08-30: -6.29 °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
2026-08-30-6.29

Error distribution

Distribution of the signed daily error in °F for Aurora (GFS init) at ALL, lead day 1-10 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: 0 days-3 to -2 °F: 0 days-2 to -1 °F: 0 days-1 to 0 °F: 0 days0 to 1 °F: 0 days1 to 2 °F: 0 days2 to 3 °F: 0 days3 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| 6.29 · P90 |e| 6.29 °F-100+10 °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
-10.00-9.000
-9.00-8.000
-8.00-7.000
-7.00-6.001
-6.00-5.000
-5.00-4.000
-4.00-3.000
-3.00-2.000
-2.00-1.000
-1.00+0.000
+0.00+1.000
+1.00+2.000
+2.00+3.000
+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
2026-0816.29 -6.29

Availability

ModelScored period DaysCoverage
Aurora (GFS init)2026-08-30 → 2026-08-30 1
Aurora (GFS init)2026-08-30 → 2026-08-30 1
Aurora (GFS init)2026-08-29 → 2026-08-30 2
Aurora (GFS 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 (GFS init) has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 1 +3.21 [3.21, 3.21] yes
Aurora (IFS init) 1 +1.22 [1.22, 1.22] yes
FourCastNet v2 (GFS init) 1 +2.39 [2.39, 2.39] yes
FourCastNet v2 (IFS init) 1 +2.62 [2.62, 2.62] yes
NCEP GFS 1 +3.64 [3.64, 3.64] yes
GraphCast (GFS init) 1 +0.34 [0.34, 0.34] yes
GraphCast (IFS init) 1 +1.03 [1.03, 1.03] yes
ECMWF IFS HRES 1 +2.99 [2.99, 2.99] yes
Pangu-Weather (GFS init) 1 +2.78 [2.78, 2.78] yes
Pangu-Weather (IFS init) 1 +2.55 [2.55, 2.55] yes
Persistence (baseline) 1 +3.12 [3.12, 3.12] yes

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: ALL (All stations (mean of daily station errors)), model aurora_gfs, 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/ALL/model/aurora_gfs/lead/1/

Accessed2026-08-31 (data through 2026-08-30; page built 2026-08-31T03:52:06+00:00)

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