Raw model output on the native 0.25° grid — no MOS, no bias correction, no post-processing. Scores understate operational forecast quality. Read the fairness statement →

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

San Francisco Intl · Pangu-Weather (IFS init) · lead day 2

KSFO · pangu_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, PANG_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 QC6.39 [6.39, 6.39]0.00-6.39 [-6.39, -6.39]6.39 [6.39, 6.39]0% [0%, 0%]0%0%-0.06—2026-08-30 → 2026-08-30
tmax00Zbilinear90d1 1 QC6.39 [6.39, 6.39]0.00-6.39 [-6.39, -6.39]6.39 [6.39, 6.39]0% [0%, 0%]0%0%-0.06—2026-08-30 → 2026-08-30
tmax00Zbilinear365d1 1 QC6.39 [6.39, 6.39]0.00-6.39 [-6.39, -6.39]6.39 [6.39, 6.39]0% [0%, 0%]0%0%-0.06—2026-08-30 → 2026-08-30
tmax00Zbilinearall1 1 QC6.39 [6.39, 6.39]0.00-6.39 [-6.39, -6.39]6.39 [6.39, 6.39]0% [0%, 0%]0%0%-0.06—2026-08-30 → 2026-08-30
tmax00Znearest30d1 1 QC6.37 [6.37, 6.37]0.00-6.37 [-6.37, -6.37]6.37 [6.37, 6.37]0% [0%, 0%]0%0%-0.06—2026-08-30 → 2026-08-30
tmax00Znearest90d1 1 QC6.37 [6.37, 6.37]0.00-6.37 [-6.37, -6.37]6.37 [6.37, 6.37]0% [0%, 0%]0%0%-0.06—2026-08-30 → 2026-08-30
tmax00Znearest365d1 1 QC6.37 [6.37, 6.37]0.00-6.37 [-6.37, -6.37]6.37 [6.37, 6.37]0% [0%, 0%]0%0%-0.06—2026-08-30 → 2026-08-30
tmax00Znearestall1 1 QC6.37 [6.37, 6.37]0.00-6.37 [-6.37, -6.37]6.37 [6.37, 6.37]0% [0%, 0%]0%0%-0.06—2026-08-30 → 2026-08-30
tmax12Zbilinear30d1 1 QC4.02 [4.02, 4.02]0.00-4.02 [-4.02, -4.02]4.02 [4.02, 4.02]0% [0%, 0%]0%0%+0.33—2026-08-30 → 2026-08-30
tmax12Zbilinear90d1 1 QC4.02 [4.02, 4.02]0.00-4.02 [-4.02, -4.02]4.02 [4.02, 4.02]0% [0%, 0%]0%0%+0.33—2026-08-30 → 2026-08-30
tmax12Zbilinear365d1 1 QC4.02 [4.02, 4.02]0.00-4.02 [-4.02, -4.02]4.02 [4.02, 4.02]0% [0%, 0%]0%0%+0.33—2026-08-30 → 2026-08-30
tmax12Zbilinearall1 1 QC4.02 [4.02, 4.02]0.00-4.02 [-4.02, -4.02]4.02 [4.02, 4.02]0% [0%, 0%]0%0%+0.33—2026-08-30 → 2026-08-30
tmax12Znearest30d1 1 QC3.89 [3.89, 3.89]0.00-3.89 [-3.89, -3.89]3.89 [3.89, 3.89]0% [0%, 0%]0%0%+0.35—2026-08-30 → 2026-08-30
tmax12Znearest90d1 1 QC3.89 [3.89, 3.89]0.00-3.89 [-3.89, -3.89]3.89 [3.89, 3.89]0% [0%, 0%]0%0%+0.35—2026-08-30 → 2026-08-30
tmax12Znearest365d1 1 QC3.89 [3.89, 3.89]0.00-3.89 [-3.89, -3.89]3.89 [3.89, 3.89]0% [0%, 0%]0%0%+0.35—2026-08-30 → 2026-08-30
tmax12Znearestall1 1 QC3.89 [3.89, 3.89]0.00-3.89 [-3.89, -3.89]3.89 [3.89, 3.89]0% [0%, 0%]0%0%+0.35—2026-08-30 → 2026-08-30
tmin00Zbilinear30d1 1 QC0.08 [0.08, 0.08]0.00+0.08 [0.08, 0.08]0.08 [0.08, 0.08]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Zbilinear90d1 1 QC0.08 [0.08, 0.08]0.00+0.08 [0.08, 0.08]0.08 [0.08, 0.08]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Zbilinear365d1 1 QC0.08 [0.08, 0.08]0.00+0.08 [0.08, 0.08]0.08 [0.08, 0.08]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Zbilinearall1 1 QC0.08 [0.08, 0.08]0.00+0.08 [0.08, 0.08]0.08 [0.08, 0.08]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Znearest30d1 1 QC0.42 [0.42, 0.42]0.00-0.42 [-0.42, -0.42]0.42 [0.42, 0.42]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Znearest90d1 1 QC0.42 [0.42, 0.42]0.00-0.42 [-0.42, -0.42]0.42 [0.42, 0.42]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Znearest365d1 1 QC0.42 [0.42, 0.42]0.00-0.42 [-0.42, -0.42]0.42 [0.42, 0.42]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Znearestall1 1 QC0.42 [0.42, 0.42]0.00-0.42 [-0.42, -0.42]0.42 [0.42, 0.42]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin12Zbilinear30d1 1 QC2.54 [2.54, 2.54]0.00-2.54 [-2.54, -2.54]2.54 [2.54, 2.54]0% [0%, 0%]0%100%——2026-08-30 → 2026-08-30
tmin12Zbilinear90d1 1 QC2.54 [2.54, 2.54]0.00-2.54 [-2.54, -2.54]2.54 [2.54, 2.54]0% [0%, 0%]0%100%——2026-08-30 → 2026-08-30
tmin12Zbilinear365d1 1 QC2.54 [2.54, 2.54]0.00-2.54 [-2.54, -2.54]2.54 [2.54, 2.54]0% [0%, 0%]0%100%——2026-08-30 → 2026-08-30
tmin12Zbilinearall1 1 QC2.54 [2.54, 2.54]0.00-2.54 [-2.54, -2.54]2.54 [2.54, 2.54]0% [0%, 0%]0%100%——2026-08-30 → 2026-08-30
tmin12Znearest30d1 1 QC2.37 [2.37, 2.37]0.00-2.37 [-2.37, -2.37]2.37 [2.37, 2.37]0% [0%, 0%]0%100%——2026-08-30 → 2026-08-30
tmin12Znearest90d1 1 QC2.37 [2.37, 2.37]0.00-2.37 [-2.37, -2.37]2.37 [2.37, 2.37]0% [0%, 0%]0%100%——2026-08-30 → 2026-08-30
tmin12Znearest365d1 1 QC2.37 [2.37, 2.37]0.00-2.37 [-2.37, -2.37]2.37 [2.37, 2.37]0% [0%, 0%]0%100%——2026-08-30 → 2026-08-30
tmin12Znearestall1 1 QC2.37 [2.37, 2.37]0.00-2.37 [-2.37, -2.37]2.37 [2.37, 2.37]0% [0%, 0%]0%100%——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 Pangu-Weather (IFS init) at KSFO, lead day 2, 00Z bilinear tmax+10+50-5-102026-08-30: -6.39 °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
2026-08-30-6.39

Error distribution

Distribution of the signed daily error in °F for Pangu-Weather (IFS init) at KSFO, lead day 2-10 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| 6.39 · P90 |e| 6.39 °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
2026-0816.39 -6.39

Availability

ModelScored period DaysCoverage
Pangu-Weather (IFS init)2026-08-30 → 2026-08-30 1
Pangu-Weather (IFS init)2026-08-30 → 2026-08-30 1
Pangu-Weather (IFS init)2026-08-30 → 2026-08-30 1
Pangu-Weather (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 Pangu-Weather (IFS init) has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 1 +0.67 [0.67, 0.67] yes
Aurora (IFS init) 1 -1.95 [-1.95, -1.95] yes
FourCastNet v2 (IFS init) 1 +4.77 [4.77, 4.77] yes
NCEP GFS 1 -0.81 [-0.81, -0.81] yes
GraphCast (IFS init) 1 +0.38 [0.38, 0.38] yes
ECMWF IFS HRES 1 -2.56 [-2.56, -2.56] yes
Persistence (baseline) 1 +0.39 [0.39, 0.39] yes

Cite this page

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

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