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

San Francisco Intl · Aurora (IFS init) · lead day 1

KSFO · aurora_ifs · 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, 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
tmax00Zbilinear30d2 1 QC8.32 [8.31, 8.34]0.02-8.32 [-8.34, -8.31]8.32 [8.31, 8.34]0% [0%, 0%]0%0%-1.77+0.992026-08-29 → 2026-08-30
tmax00Zbilinear90d2 1 QC8.32 [8.31, 8.34]0.02-8.32 [-8.34, -8.31]8.32 [8.31, 8.34]0% [0%, 0%]0%0%-1.77+0.992026-08-29 → 2026-08-30
tmax00Zbilinear365d2 1 QC8.32 [8.31, 8.34]0.02-8.32 [-8.34, -8.31]8.32 [8.31, 8.34]0% [0%, 0%]0%0%-1.77+0.992026-08-29 → 2026-08-30
tmax00Zbilinearall2 1 QC8.32 [8.31, 8.34]0.02-8.32 [-8.34, -8.31]8.32 [8.31, 8.34]0% [0%, 0%]0%0%-1.77+0.992026-08-29 → 2026-08-30
tmax00Znearest30d2 1 QC1.93 [1.04, 2.82]0.89-1.93 [-2.82, -1.04]2.13 [1.04, 2.82]0% [0%, 0%]50%100%+0.36+0.702026-08-29 → 2026-08-30
tmax00Znearest90d2 1 QC1.93 [1.04, 2.82]0.89-1.93 [-2.82, -1.04]2.13 [1.04, 2.82]0% [0%, 0%]50%100%+0.36+0.702026-08-29 → 2026-08-30
tmax00Znearest365d2 1 QC1.93 [1.04, 2.82]0.89-1.93 [-2.82, -1.04]2.13 [1.04, 2.82]0% [0%, 0%]50%100%+0.36+0.702026-08-29 → 2026-08-30
tmax00Znearestall2 1 QC1.93 [1.04, 2.82]0.89-1.93 [-2.82, -1.04]2.13 [1.04, 2.82]0% [0%, 0%]50%100%+0.36+0.702026-08-29 → 2026-08-30
tmax12Zbilinear30d2 1 QC8.56 [8.36, 8.75]0.19-8.56 [-8.75, -8.36]8.56 [8.36, 8.75]0% [0%, 0%]0%0%-1.85+0.942026-08-29 → 2026-08-30
tmax12Zbilinear90d2 1 QC8.56 [8.36, 8.75]0.19-8.56 [-8.75, -8.36]8.56 [8.36, 8.75]0% [0%, 0%]0%0%-1.85+0.942026-08-29 → 2026-08-30
tmax12Zbilinear365d2 1 QC8.56 [8.36, 8.75]0.19-8.56 [-8.75, -8.36]8.56 [8.36, 8.75]0% [0%, 0%]0%0%-1.85+0.942026-08-29 → 2026-08-30
tmax12Zbilinearall2 1 QC8.56 [8.36, 8.75]0.19-8.56 [-8.75, -8.36]8.56 [8.36, 8.75]0% [0%, 0%]0%0%-1.85+0.942026-08-29 → 2026-08-30
tmax12Znearest30d2 1 QC2.14 [1.81, 2.47]0.33-2.14 [-2.47, -1.81]2.17 [1.81, 2.47]0% [0%, 0%]50%100%+0.29+0.892026-08-29 → 2026-08-30
tmax12Znearest90d2 1 QC2.14 [1.81, 2.47]0.33-2.14 [-2.47, -1.81]2.17 [1.81, 2.47]0% [0%, 0%]50%100%+0.29+0.892026-08-29 → 2026-08-30
tmax12Znearest365d2 1 QC2.14 [1.81, 2.47]0.33-2.14 [-2.47, -1.81]2.17 [1.81, 2.47]0% [0%, 0%]50%100%+0.29+0.892026-08-29 → 2026-08-30
tmax12Znearestall2 1 QC2.14 [1.81, 2.47]0.33-2.14 [-2.47, -1.81]2.17 [1.81, 2.47]0% [0%, 0%]50%100%+0.29+0.892026-08-29 → 2026-08-30
tmin00Zbilinear30d2 1 QC1.11 [0.82, 1.40]1.11-0.29 [-1.40, 0.82]1.15 [0.82, 1.40]50% [0%, 100%]100%100%-0.11-0.112026-08-29 → 2026-08-30
tmin00Zbilinear90d2 1 QC1.11 [0.82, 1.40]1.11-0.29 [-1.40, 0.82]1.15 [0.82, 1.40]50% [0%, 100%]100%100%-0.11-0.112026-08-29 → 2026-08-30
tmin00Zbilinear365d2 1 QC1.11 [0.82, 1.40]1.11-0.29 [-1.40, 0.82]1.15 [0.82, 1.40]50% [0%, 100%]100%100%-0.11-0.112026-08-29 → 2026-08-30
tmin00Zbilinearall2 1 QC1.11 [0.82, 1.40]1.11-0.29 [-1.40, 0.82]1.15 [0.82, 1.40]50% [0%, 100%]100%100%-0.11-0.112026-08-29 → 2026-08-30
tmin00Znearest30d2 1 QC1.22 [0.51, 1.92]1.22-0.71 [-1.92, 0.51]1.41 [0.51, 1.92]50% [0%, 100%]100%100%-0.22-0.222026-08-29 → 2026-08-30
tmin00Znearest90d2 1 QC1.22 [0.51, 1.92]1.22-0.71 [-1.92, 0.51]1.41 [0.51, 1.92]50% [0%, 100%]100%100%-0.22-0.222026-08-29 → 2026-08-30
tmin00Znearest365d2 1 QC1.22 [0.51, 1.92]1.22-0.71 [-1.92, 0.51]1.41 [0.51, 1.92]50% [0%, 100%]100%100%-0.22-0.222026-08-29 → 2026-08-30
tmin00Znearestall2 1 QC1.22 [0.51, 1.92]1.22-0.71 [-1.92, 0.51]1.41 [0.51, 1.92]50% [0%, 100%]100%100%-0.22-0.222026-08-29 → 2026-08-30
tmin12Zbilinear30d2 1 QC0.84 [0.26, 1.42]0.84-0.58 [-1.42, 0.26]1.02 [0.26, 1.42]50% [0%, 100%]100%100%+0.16+0.162026-08-29 → 2026-08-30
tmin12Zbilinear90d2 1 QC0.84 [0.26, 1.42]0.84-0.58 [-1.42, 0.26]1.02 [0.26, 1.42]50% [0%, 100%]100%100%+0.16+0.162026-08-29 → 2026-08-30
tmin12Zbilinear365d2 1 QC0.84 [0.26, 1.42]0.84-0.58 [-1.42, 0.26]1.02 [0.26, 1.42]50% [0%, 100%]100%100%+0.16+0.162026-08-29 → 2026-08-30
tmin12Zbilinearall2 1 QC0.84 [0.26, 1.42]0.84-0.58 [-1.42, 0.26]1.02 [0.26, 1.42]50% [0%, 100%]100%100%+0.16+0.162026-08-29 → 2026-08-30
tmin12Znearest30d2 1 QC0.92 [0.04, 1.80]0.88-0.92 [-1.80, -0.04]1.27 [0.04, 1.80]50% [0%, 100%]100%100%+0.08+0.122026-08-29 → 2026-08-30
tmin12Znearest90d2 1 QC0.92 [0.04, 1.80]0.88-0.92 [-1.80, -0.04]1.27 [0.04, 1.80]50% [0%, 100%]100%100%+0.08+0.122026-08-29 → 2026-08-30
tmin12Znearest365d2 1 QC0.92 [0.04, 1.80]0.88-0.92 [-1.80, -0.04]1.27 [0.04, 1.80]50% [0%, 100%]100%100%+0.08+0.122026-08-29 → 2026-08-30
tmin12Znearestall2 1 QC0.92 [0.04, 1.80]0.88-0.92 [-1.80, -0.04]1.27 [0.04, 1.80]50% [0%, 100%]100%100%+0.08+0.122026-08-29 → 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 (IFS init) at KSFO, lead day 1, 00Z bilinear tmax+10+50-5-102026-08-29: -8.34 °F2026-08-30: -8.31 °F2026-08-292026-08-30°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 (2 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-8.31
2026-08-29-8.34

Error distribution

Distribution of the signed daily error in °F for Aurora (IFS init) at KSFO, lead day 1-10 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: 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| 8.32 · P90 |e| 8.34 °F-100+10 °Fn = 2 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+0.000
+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
2026-0828.32 -8.32

Availability

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

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 2 +2.69 [2.40, 2.98] yes
Aurora (GFS init) 1 +1.67 [1.67, 1.67] yes
FourCastNet v2 (GFS init) 1 +6.90 [6.90, 6.90] yes
FourCastNet v2 (IFS init) 2 +5.88 [5.77, 5.98] yes
NCEP GFS 2 +1.74 [1.11, 2.37] yes
GraphCast (GFS init) 1 +3.67 [3.67, 3.67] yes
GraphCast (IFS init) 2 +2.90 [2.23, 3.56] yes
ECMWF IFS HRES 2 -0.18 [-0.79, 0.43] no
Pangu-Weather (GFS init) 1 +1.66 [1.66, 1.66] yes
Pangu-Weather (IFS init) 2 +1.62 [1.49, 1.75] yes
Persistence (baseline) 2 +5.32 [2.34, 8.31] yes

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSFO (San Francisco Intl), model aurora_ifs, 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/KSFO/model/aurora_ifs/lead/1/

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