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

Trenton Mercer · Aurora (IFS init) · lead day 0

KTTN · aurora_ifs · lead 0

Target day = initialization date + 0 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
tmax00Zbilinear30d3 1 QC0.96 [0.10, 1.83]0.66-0.89 [-1.83, 0.10]1.19 [0.10, 1.83]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmax00Zbilinear90d3 1 QC0.96 [0.10, 1.83]0.66-0.89 [-1.83, 0.10]1.19 [0.10, 1.83]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmax00Zbilinear365d3 1 QC0.96 [0.10, 1.83]0.66-0.89 [-1.83, 0.10]1.19 [0.10, 1.83]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmax00Zbilinearall3 1 QC0.96 [0.10, 1.83]0.66-0.89 [-1.83, 0.10]1.19 [0.10, 1.83]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmax00Znearest30d3 1 QC0.91 [0.49, 1.65]0.71-0.58 [-1.65, 0.49]1.05 [0.49, 1.65]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmax00Znearest90d3 1 QC0.91 [0.49, 1.65]0.71-0.58 [-1.65, 0.49]1.05 [0.49, 1.65]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmax00Znearest365d3 1 QC0.91 [0.49, 1.65]0.71-0.58 [-1.65, 0.49]1.05 [0.49, 1.65]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmax00Znearestall3 1 QC0.91 [0.49, 1.65]0.71-0.58 [-1.65, 0.49]1.05 [0.49, 1.65]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmin00Zbilinear30d3 1 QC3.28 [2.93, 3.45]0.41+3.28 [2.93, 3.45]3.31 [2.93, 3.48]0% [0%, 0%]0%33%——2026-08-28 → 2026-08-30
tmin00Zbilinear90d3 1 QC3.28 [2.93, 3.45]0.41+3.28 [2.93, 3.45]3.31 [2.93, 3.48]0% [0%, 0%]0%33%——2026-08-28 → 2026-08-30
tmin00Zbilinear365d3 1 QC3.28 [2.93, 3.45]0.41+3.28 [2.93, 3.45]3.31 [2.93, 3.48]0% [0%, 0%]0%33%——2026-08-28 → 2026-08-30
tmin00Zbilinearall3 1 QC3.28 [2.93, 3.45]0.41+3.28 [2.93, 3.45]3.31 [2.93, 3.48]0% [0%, 0%]0%33%——2026-08-28 → 2026-08-30
tmin00Znearest30d3 1 QC3.49 [3.01, 3.73]0.55+3.49 [3.01, 3.73]3.54 [3.01, 3.78]0% [0%, 0%]0%0%——2026-08-28 → 2026-08-30
tmin00Znearest90d3 1 QC3.49 [3.01, 3.73]0.55+3.49 [3.01, 3.73]3.54 [3.01, 3.78]0% [0%, 0%]0%0%——2026-08-28 → 2026-08-30
tmin00Znearest365d3 1 QC3.49 [3.01, 3.73]0.55+3.49 [3.01, 3.73]3.54 [3.01, 3.78]0% [0%, 0%]0%0%——2026-08-28 → 2026-08-30
tmin00Znearestall3 1 QC3.49 [3.01, 3.73]0.55+3.49 [3.01, 3.73]3.54 [3.01, 3.78]0% [0%, 0%]0%0%——2026-08-28 → 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 0, 00Z bilinear tmax+2+10-1-22026-08-28: -1.83 °F2026-08-29: -0.95 °F2026-08-30: +0.1 °F2026-08-282026-08-30°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 (3 days, newest first) · download CSV
Climatological dayError °F
2026-08-30+0.10
2026-08-29-0.95
2026-08-28-1.83

Error distribution

Distribution of the signed daily error in °F for Aurora (IFS init) at KTTN, lead day 0-2 to -1.8 °F: 1 day-1.8 to -1.6 °F: 0 days-1.6 to -1.4 °F: 0 days-1.4 to -1.2 °F: 0 days-1.2 to -1 °F: 0 days-1 to -0.8 °F: 1 day-0.8 to -0.6 °F: 0 days-0.6 to -0.4 °F: 0 days-0.4 to -0.2 °F: 0 days-0.2 to 0 °F: 0 days0 to 0.2 °F: 1 day0.2 to 0.4 °F: 0 days0.4 to 0.6 °F: 0 days0.6 to 0.8 °F: 0 days0.8 to 1 °F: 0 days1 to 1.2 °F: 0 days1.2 to 1.4 °F: 0 days1.4 to 1.6 °F: 0 days1.6 to 1.8 °F: 0 days1.8 to 2 °F: 0 daysdashed: P50 |e| 0.95 · P90 |e| 1.65 °F-20+2 °Fn = 3 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
-2.00-1.801
-1.80-1.600
-1.60-1.400
-1.40-1.200
-1.20-1.000
-1.00-0.801
-0.80-0.600
-0.60-0.400
-0.40-0.200
-0.20+0.000
+0.00+0.201
+0.20+0.400
+0.40+0.600
+0.60+0.800
+0.80+1.000
+1.00+1.200
+1.20+1.400
+1.40+1.600
+1.60+1.800
+1.80+2.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-0830.96 -0.89

Availability

ModelScored period DaysCoverage
Aurora (IFS init)2026-08-28 → 2026-08-30 3
Aurora (IFS init)2026-08-28 → 2026-08-30 3

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 3 -0.68 [-1.67, 0.61] no
Aurora (GFS init) 2 -1.10 [-2.45, 0.26] no
FourCastNet v2 (GFS init) 2 -2.08 [-3.67, -0.48] yes
FourCastNet v2 (IFS init) 3 -1.76 [-3.01, -1.14] yes
NCEP GFS 3 -0.83 [-1.18, -0.14] yes
GraphCast (GFS init) 2 -1.24 [-2.52, 0.04] no
GraphCast (IFS init) 3 -0.64 [-0.79, -0.54] yes
ECMWF IFS HRES 3 -0.53 [-1.30, -0.15] yes
Pangu-Weather (GFS init) 2 -1.73 [-1.89, -1.58] yes
Pangu-Weather (IFS init) 3 -0.63 [-1.82, 1.75] no

Cite this page

ShortCastCheck, KTTN aurora_ifs lead 0, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KTTN/model/aurora_ifs/lead/0/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KTTN (Trenton Mercer), model aurora_ifs, lead day 0. 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/0/

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