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

Trenton Mercer · Aurora (IFS init) · lead day 2

KTTN · 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 QC0.31 [0.31, 0.31]0.00+0.31 [0.31, 0.31]0.31 [0.31, 0.31]100% [100%, 100%]100%100%+0.69—2026-08-30 → 2026-08-30
tmax00Zbilinear90d1 1 QC0.31 [0.31, 0.31]0.00+0.31 [0.31, 0.31]0.31 [0.31, 0.31]100% [100%, 100%]100%100%+0.69—2026-08-30 → 2026-08-30
tmax00Zbilinear365d1 1 QC0.31 [0.31, 0.31]0.00+0.31 [0.31, 0.31]0.31 [0.31, 0.31]100% [100%, 100%]100%100%+0.69—2026-08-30 → 2026-08-30
tmax00Zbilinearall1 1 QC0.31 [0.31, 0.31]0.00+0.31 [0.31, 0.31]0.31 [0.31, 0.31]100% [100%, 100%]100%100%+0.69—2026-08-30 → 2026-08-30
tmax00Znearest30d1 1 QC0.74 [0.74, 0.74]0.00+0.74 [0.74, 0.74]0.74 [0.74, 0.74]100% [100%, 100%]100%100%+0.26—2026-08-30 → 2026-08-30
tmax00Znearest90d1 1 QC0.74 [0.74, 0.74]0.00+0.74 [0.74, 0.74]0.74 [0.74, 0.74]100% [100%, 100%]100%100%+0.26—2026-08-30 → 2026-08-30
tmax00Znearest365d1 1 QC0.74 [0.74, 0.74]0.00+0.74 [0.74, 0.74]0.74 [0.74, 0.74]100% [100%, 100%]100%100%+0.26—2026-08-30 → 2026-08-30
tmax00Znearestall1 1 QC0.74 [0.74, 0.74]0.00+0.74 [0.74, 0.74]0.74 [0.74, 0.74]100% [100%, 100%]100%100%+0.26—2026-08-30 → 2026-08-30
tmax12Zbilinear30d1 1 QC1.04 [1.04, 1.04]0.00-1.04 [-1.04, -1.04]1.04 [1.04, 1.04]0% [0%, 0%]100%100%-0.04—2026-08-30 → 2026-08-30
tmax12Zbilinear90d1 1 QC1.04 [1.04, 1.04]0.00-1.04 [-1.04, -1.04]1.04 [1.04, 1.04]0% [0%, 0%]100%100%-0.04—2026-08-30 → 2026-08-30
tmax12Zbilinear365d1 1 QC1.04 [1.04, 1.04]0.00-1.04 [-1.04, -1.04]1.04 [1.04, 1.04]0% [0%, 0%]100%100%-0.04—2026-08-30 → 2026-08-30
tmax12Zbilinearall1 1 QC1.04 [1.04, 1.04]0.00-1.04 [-1.04, -1.04]1.04 [1.04, 1.04]0% [0%, 0%]100%100%-0.04—2026-08-30 → 2026-08-30
tmax12Znearest30d1 1 QC0.59 [0.59, 0.59]0.00-0.59 [-0.59, -0.59]0.59 [0.59, 0.59]100% [100%, 100%]100%100%+0.41—2026-08-30 → 2026-08-30
tmax12Znearest90d1 1 QC0.59 [0.59, 0.59]0.00-0.59 [-0.59, -0.59]0.59 [0.59, 0.59]100% [100%, 100%]100%100%+0.41—2026-08-30 → 2026-08-30
tmax12Znearest365d1 1 QC0.59 [0.59, 0.59]0.00-0.59 [-0.59, -0.59]0.59 [0.59, 0.59]100% [100%, 100%]100%100%+0.41—2026-08-30 → 2026-08-30
tmax12Znearestall1 1 QC0.59 [0.59, 0.59]0.00-0.59 [-0.59, -0.59]0.59 [0.59, 0.59]100% [100%, 100%]100%100%+0.41—2026-08-30 → 2026-08-30
tmin00Zbilinear30d1 1 QC5.28 [5.28, 5.28]0.00+5.28 [5.28, 5.28]5.28 [5.28, 5.28]0% [0%, 0%]0%0%+0.34—2026-08-30 → 2026-08-30
tmin00Zbilinear90d1 1 QC5.28 [5.28, 5.28]0.00+5.28 [5.28, 5.28]5.28 [5.28, 5.28]0% [0%, 0%]0%0%+0.34—2026-08-30 → 2026-08-30
tmin00Zbilinear365d1 1 QC5.28 [5.28, 5.28]0.00+5.28 [5.28, 5.28]5.28 [5.28, 5.28]0% [0%, 0%]0%0%+0.34—2026-08-30 → 2026-08-30
tmin00Zbilinearall1 1 QC5.28 [5.28, 5.28]0.00+5.28 [5.28, 5.28]5.28 [5.28, 5.28]0% [0%, 0%]0%0%+0.34—2026-08-30 → 2026-08-30
tmin00Znearest30d1 1 QC5.40 [5.40, 5.40]0.00+5.40 [5.40, 5.40]5.40 [5.40, 5.40]0% [0%, 0%]0%0%+0.33—2026-08-30 → 2026-08-30
tmin00Znearest90d1 1 QC5.40 [5.40, 5.40]0.00+5.40 [5.40, 5.40]5.40 [5.40, 5.40]0% [0%, 0%]0%0%+0.33—2026-08-30 → 2026-08-30
tmin00Znearest365d1 1 QC5.40 [5.40, 5.40]0.00+5.40 [5.40, 5.40]5.40 [5.40, 5.40]0% [0%, 0%]0%0%+0.33—2026-08-30 → 2026-08-30
tmin00Znearestall1 1 QC5.40 [5.40, 5.40]0.00+5.40 [5.40, 5.40]5.40 [5.40, 5.40]0% [0%, 0%]0%0%+0.33—2026-08-30 → 2026-08-30
tmin12Zbilinear30d1 1 QC4.25 [4.25, 4.25]0.00+4.25 [4.25, 4.25]4.25 [4.25, 4.25]0% [0%, 0%]0%0%+0.47—2026-08-30 → 2026-08-30
tmin12Zbilinear90d1 1 QC4.25 [4.25, 4.25]0.00+4.25 [4.25, 4.25]4.25 [4.25, 4.25]0% [0%, 0%]0%0%+0.47—2026-08-30 → 2026-08-30
tmin12Zbilinear365d1 1 QC4.25 [4.25, 4.25]0.00+4.25 [4.25, 4.25]4.25 [4.25, 4.25]0% [0%, 0%]0%0%+0.47—2026-08-30 → 2026-08-30
tmin12Zbilinearall1 1 QC4.25 [4.25, 4.25]0.00+4.25 [4.25, 4.25]4.25 [4.25, 4.25]0% [0%, 0%]0%0%+0.47—2026-08-30 → 2026-08-30
tmin12Znearest30d1 1 QC4.35 [4.35, 4.35]0.00+4.35 [4.35, 4.35]4.35 [4.35, 4.35]0% [0%, 0%]0%0%+0.46—2026-08-30 → 2026-08-30
tmin12Znearest90d1 1 QC4.35 [4.35, 4.35]0.00+4.35 [4.35, 4.35]4.35 [4.35, 4.35]0% [0%, 0%]0%0%+0.46—2026-08-30 → 2026-08-30
tmin12Znearest365d1 1 QC4.35 [4.35, 4.35]0.00+4.35 [4.35, 4.35]4.35 [4.35, 4.35]0% [0%, 0%]0%0%+0.46—2026-08-30 → 2026-08-30
tmin12Znearestall1 1 QC4.35 [4.35, 4.35]0.00+4.35 [4.35, 4.35]4.35 [4.35, 4.35]0% [0%, 0%]0%0%+0.46—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 KTTN, lead day 2, 00Z bilinear tmax+0.5+0.20-0.2-0.52026-08-30: +0.31 °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+0.31

Error distribution

Distribution of the signed daily error in °F for Aurora (IFS init) at KTTN, lead day 2-0.5 to -0.45 °F: 0 days-0.45 to -0.4 °F: 0 days-0.4 to -0.35 °F: 0 days-0.35 to -0.3 °F: 0 days-0.3 to -0.25 °F: 0 days-0.25 to -0.2 °F: 0 days-0.2 to -0.15 °F: 0 days-0.15 to -0.1 °F: 0 days-0.1 to -0.05 °F: 0 days-0.05 to 0 °F: 0 days0 to 0.05 °F: 0 days0.05 to 0.1 °F: 0 days0.1 to 0.15 °F: 0 days0.15 to 0.2 °F: 0 days0.2 to 0.25 °F: 0 days0.25 to 0.3 °F: 0 days0.3 to 0.35 °F: 1 day0.35 to 0.4 °F: 0 days0.4 to 0.45 °F: 0 days0.45 to 0.5 °F: 0 daysdashed: P50 |e| 0.31 · P90 |e| 0.31 °F-0.50+0.5 °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
-0.50-0.450
-0.45-0.400
-0.40-0.350
-0.35-0.300
-0.30-0.250
-0.25-0.200
-0.20-0.150
-0.15-0.100
-0.10-0.050
-0.05+0.000
+0.00+0.050
+0.05+0.100
+0.10+0.150
+0.15+0.200
+0.20+0.250
+0.25+0.300
+0.30+0.351
+0.35+0.400
+0.40+0.450
+0.45+0.500

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-0810.31 +0.31

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 -0.33 [-0.33, -0.33] yes
FourCastNet v2 (IFS init) 1 -0.76 [-0.76, -0.76] yes
NCEP GFS 1 -4.88 [-4.88, -4.88] yes
GraphCast (IFS init) 1 -0.59 [-0.59, -0.59] yes
ECMWF IFS HRES 1 -1.38 [-1.38, -1.38] yes
Pangu-Weather (IFS init) 1 -1.80 [-1.80, -1.80] yes
Persistence (baseline) 1 -0.69 [-0.69, -0.69] yes

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KTTN (Trenton Mercer), 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/KTTN/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