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

San Francisco Intl · Aurora (IFS init) · lead day 0

KSFO · 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 QC5.42 [0.03, 8.17]3.60-5.42 [-8.17, -0.03]6.63 [0.03, 8.17]33% [0%, 100%]33%33%——2026-08-28 → 2026-08-30
tmax00Zbilinear90d3 1 QC5.42 [0.03, 8.17]3.60-5.42 [-8.17, -0.03]6.63 [0.03, 8.17]33% [0%, 100%]33%33%——2026-08-28 → 2026-08-30
tmax00Zbilinear365d3 1 QC5.42 [0.03, 8.17]3.60-5.42 [-8.17, -0.03]6.63 [0.03, 8.17]33% [0%, 100%]33%33%——2026-08-28 → 2026-08-30
tmax00Zbilinearall3 1 QC5.42 [0.03, 8.17]3.60-5.42 [-8.17, -0.03]6.63 [0.03, 8.17]33% [0%, 100%]33%33%——2026-08-28 → 2026-08-30
tmax00Znearest30d3 1 QC3.41 [1.37, 6.64]3.75+1.02 [-1.80, 6.64]4.12 [1.37, 6.64]0% [0%, 0%]33%67%——2026-08-28 → 2026-08-30
tmax00Znearest90d3 1 QC3.41 [1.37, 6.64]3.75+1.02 [-1.80, 6.64]4.12 [1.37, 6.64]0% [0%, 0%]33%67%——2026-08-28 → 2026-08-30
tmax00Znearest365d3 1 QC3.41 [1.37, 6.64]3.75+1.02 [-1.80, 6.64]4.12 [1.37, 6.64]0% [0%, 0%]33%67%——2026-08-28 → 2026-08-30
tmax00Znearestall3 1 QC3.41 [1.37, 6.64]3.75+1.02 [-1.80, 6.64]4.12 [1.37, 6.64]0% [0%, 0%]33%67%——2026-08-28 → 2026-08-30
tmin00Zbilinear30d3 1 QC0.98 [0.78, 1.39]0.86+0.35 [-0.94, 1.39]1.03 [0.79, 1.39]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmin00Zbilinear90d3 1 QC0.98 [0.78, 1.39]0.86+0.35 [-0.94, 1.39]1.03 [0.79, 1.39]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmin00Zbilinear365d3 1 QC0.98 [0.78, 1.39]0.86+0.35 [-0.94, 1.39]1.03 [0.79, 1.39]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmin00Zbilinearall3 1 QC0.98 [0.78, 1.39]0.86+0.35 [-0.94, 1.39]1.03 [0.79, 1.39]67% [0%, 100%]100%100%——2026-08-28 → 2026-08-30
tmin00Znearest30d3 1 QC1.07 [0.63, 1.96]1.15+0.23 [-1.26, 1.96]1.34 [0.89, 1.96]33% [0%, 50%]100%100%——2026-08-28 → 2026-08-30
tmin00Znearest90d3 1 QC1.07 [0.63, 1.96]1.15+0.23 [-1.26, 1.96]1.34 [0.89, 1.96]33% [0%, 50%]100%100%——2026-08-28 → 2026-08-30
tmin00Znearest365d3 1 QC1.07 [0.63, 1.96]1.15+0.23 [-1.26, 1.96]1.34 [0.89, 1.96]33% [0%, 50%]100%100%——2026-08-28 → 2026-08-30
tmin00Znearestall3 1 QC1.07 [0.63, 1.96]1.15+0.23 [-1.26, 1.96]1.34 [0.89, 1.96]33% [0%, 50%]100%100%——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 KSFO, lead day 0, 00Z bilinear tmax+10+50-5-102026-08-28: -0.03 °F2026-08-29: -8.07 °F2026-08-30: -8.17 °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
2026-08-30-8.17
2026-08-29-8.07
2026-08-28-0.03

Error distribution

Distribution of the signed daily error in °F for Aurora (IFS init) at KSFO, lead day 0-10 to -9 °F: 0 days-9 to -8 °F: 2 days-8 to -7 °F: 0 days-7 to -6 °F: 0 days-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: 1 day0 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| 8.07 · P90 |e| 8.15 °F-100+10 °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
-10.00-9.000
-9.00-8.002
-8.00-7.000
-7.00-6.000
-6.00-5.000
-5.00-4.000
-4.00-3.000
-3.00-2.000
-2.00-1.000
-1.00+0.001
+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
2026-0835.42 -5.42

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 +1.50 [-0.45, 2.86] no
Aurora (GFS init) 2 +0.43 [0.29, 0.58] yes
FourCastNet v2 (GFS init) 2 +3.11 [2.89, 3.34] yes
FourCastNet v2 (IFS init) 3 +2.08 [-2.18, 4.22] no
NCEP GFS 3 -0.11 [-2.77, 1.22] no
GraphCast (GFS init) 2 +1.93 [1.68, 2.19] yes
GraphCast (IFS init) 3 +1.28 [-1.79, 2.94] no
ECMWF IFS HRES 3 -0.46 [-1.34, -0.03] yes
Pangu-Weather (GFS init) 2 +0.83 [0.52, 1.14] yes
Pangu-Weather (IFS init) 3 +0.68 [-0.92, 1.64] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSFO (San Francisco Intl), 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/KSFO/model/aurora_ifs/lead/0/

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

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