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

Seattle-Tacoma · Pangu-Weather (GFS init) · lead day 1

KSEA · pangu_gfs · 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, 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 QC2.42 [2.42, 2.42]0.00-2.42 [-2.42, -2.42]2.42 [2.42, 2.42]0% [0%, 0%]0%100%-1.42—2026-08-30 → 2026-08-30
tmax00Zbilinear90d1 1 QC2.42 [2.42, 2.42]0.00-2.42 [-2.42, -2.42]2.42 [2.42, 2.42]0% [0%, 0%]0%100%-1.42—2026-08-30 → 2026-08-30
tmax00Zbilinear365d1 1 QC2.42 [2.42, 2.42]0.00-2.42 [-2.42, -2.42]2.42 [2.42, 2.42]0% [0%, 0%]0%100%-1.42—2026-08-30 → 2026-08-30
tmax00Zbilinearall1 1 QC2.42 [2.42, 2.42]0.00-2.42 [-2.42, -2.42]2.42 [2.42, 2.42]0% [0%, 0%]0%100%-1.42—2026-08-30 → 2026-08-30
tmax00Znearest30d1 1 QC2.34 [2.34, 2.34]0.00-2.34 [-2.34, -2.34]2.34 [2.34, 2.34]0% [0%, 0%]0%100%-1.34—2026-08-30 → 2026-08-30
tmax00Znearest90d1 1 QC2.34 [2.34, 2.34]0.00-2.34 [-2.34, -2.34]2.34 [2.34, 2.34]0% [0%, 0%]0%100%-1.34—2026-08-30 → 2026-08-30
tmax00Znearest365d1 1 QC2.34 [2.34, 2.34]0.00-2.34 [-2.34, -2.34]2.34 [2.34, 2.34]0% [0%, 0%]0%100%-1.34—2026-08-30 → 2026-08-30
tmax00Znearestall1 1 QC2.34 [2.34, 2.34]0.00-2.34 [-2.34, -2.34]2.34 [2.34, 2.34]0% [0%, 0%]0%100%-1.34—2026-08-30 → 2026-08-30
tmax12Zbilinear30d2 1 QC4.56 [3.01, 6.12]1.56-4.56 [-6.12, -3.01]4.82 [3.01, 6.12]0% [0%, 0%]0%0%-2.04-2.122026-08-29 → 2026-08-30
tmax12Zbilinear90d2 1 QC4.56 [3.01, 6.12]1.56-4.56 [-6.12, -3.01]4.82 [3.01, 6.12]0% [0%, 0%]0%0%-2.04-2.122026-08-29 → 2026-08-30
tmax12Zbilinear365d2 1 QC4.56 [3.01, 6.12]1.56-4.56 [-6.12, -3.01]4.82 [3.01, 6.12]0% [0%, 0%]0%0%-2.04-2.122026-08-29 → 2026-08-30
tmax12Zbilinearall2 1 QC4.56 [3.01, 6.12]1.56-4.56 [-6.12, -3.01]4.82 [3.01, 6.12]0% [0%, 0%]0%0%-2.04-2.122026-08-29 → 2026-08-30
tmax12Znearest30d2 1 QC4.75 [3.10, 6.41]1.66-4.75 [-6.41, -3.10]5.03 [3.10, 6.41]0% [0%, 0%]0%0%-2.17-2.312026-08-29 → 2026-08-30
tmax12Znearest90d2 1 QC4.75 [3.10, 6.41]1.66-4.75 [-6.41, -3.10]5.03 [3.10, 6.41]0% [0%, 0%]0%0%-2.17-2.312026-08-29 → 2026-08-30
tmax12Znearest365d2 1 QC4.75 [3.10, 6.41]1.66-4.75 [-6.41, -3.10]5.03 [3.10, 6.41]0% [0%, 0%]0%0%-2.17-2.312026-08-29 → 2026-08-30
tmax12Znearestall2 1 QC4.75 [3.10, 6.41]1.66-4.75 [-6.41, -3.10]5.03 [3.10, 6.41]0% [0%, 0%]0%0%-2.17-2.312026-08-29 → 2026-08-30
tmin00Zbilinear30d1 1 QC0.98 [0.98, 0.98]0.00+0.98 [0.98, 0.98]0.98 [0.98, 0.98]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Zbilinear90d1 1 QC0.98 [0.98, 0.98]0.00+0.98 [0.98, 0.98]0.98 [0.98, 0.98]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Zbilinear365d1 1 QC0.98 [0.98, 0.98]0.00+0.98 [0.98, 0.98]0.98 [0.98, 0.98]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Zbilinearall1 1 QC0.98 [0.98, 0.98]0.00+0.98 [0.98, 0.98]0.98 [0.98, 0.98]100% [100%, 100%]100%100%——2026-08-30 → 2026-08-30
tmin00Znearest30d1 1 QC1.38 [1.38, 1.38]0.00+1.38 [1.38, 1.38]1.38 [1.38, 1.38]0% [0%, 0%]100%100%——2026-08-30 → 2026-08-30
tmin00Znearest90d1 1 QC1.38 [1.38, 1.38]0.00+1.38 [1.38, 1.38]1.38 [1.38, 1.38]0% [0%, 0%]100%100%——2026-08-30 → 2026-08-30
tmin00Znearest365d1 1 QC1.38 [1.38, 1.38]0.00+1.38 [1.38, 1.38]1.38 [1.38, 1.38]0% [0%, 0%]100%100%——2026-08-30 → 2026-08-30
tmin00Znearestall1 1 QC1.38 [1.38, 1.38]0.00+1.38 [1.38, 1.38]1.38 [1.38, 1.38]0% [0%, 0%]100%100%——2026-08-30 → 2026-08-30
tmin12Zbilinear30d2 1 QC1.51 [0.58, 2.44]1.51+0.93 [-0.58, 2.44]1.78 [0.58, 2.44]50% [0%, 100%]50%100%-0.51-0.512026-08-29 → 2026-08-30
tmin12Zbilinear90d2 1 QC1.51 [0.58, 2.44]1.51+0.93 [-0.58, 2.44]1.78 [0.58, 2.44]50% [0%, 100%]50%100%-0.51-0.512026-08-29 → 2026-08-30
tmin12Zbilinear365d2 1 QC1.51 [0.58, 2.44]1.51+0.93 [-0.58, 2.44]1.78 [0.58, 2.44]50% [0%, 100%]50%100%-0.51-0.512026-08-29 → 2026-08-30
tmin12Zbilinearall2 1 QC1.51 [0.58, 2.44]1.51+0.93 [-0.58, 2.44]1.78 [0.58, 2.44]50% [0%, 100%]50%100%-0.51-0.512026-08-29 → 2026-08-30
tmin12Znearest30d2 1 QC1.56 [0.38, 2.74]1.56+1.18 [-0.38, 2.74]1.96 [0.38, 2.74]50% [0%, 100%]50%100%-0.56-0.562026-08-29 → 2026-08-30
tmin12Znearest90d2 1 QC1.56 [0.38, 2.74]1.56+1.18 [-0.38, 2.74]1.96 [0.38, 2.74]50% [0%, 100%]50%100%-0.56-0.562026-08-29 → 2026-08-30
tmin12Znearest365d2 1 QC1.56 [0.38, 2.74]1.56+1.18 [-0.38, 2.74]1.96 [0.38, 2.74]50% [0%, 100%]50%100%-0.56-0.562026-08-29 → 2026-08-30
tmin12Znearestall2 1 QC1.56 [0.38, 2.74]1.56+1.18 [-0.38, 2.74]1.96 [0.38, 2.74]50% [0%, 100%]50%100%-0.56-0.562026-08-29 → 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 Pangu-Weather (GFS init) at KSEA, lead day 1, 00Z bilinear tmax+2.5+1.20-1.2-2.52026-08-30: -2.42 °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
2026-08-30-2.42

Error distribution

Distribution of the signed daily error in °F for Pangu-Weather (GFS init) at KSEA, lead day 1-2.5 to -2.25 °F: 1 day-2.25 to -2 °F: 0 days-2 to -1.75 °F: 0 days-1.75 to -1.5 °F: 0 days-1.5 to -1.25 °F: 0 days-1.25 to -1 °F: 0 days-1 to -0.75 °F: 0 days-0.75 to -0.5 °F: 0 days-0.5 to -0.25 °F: 0 days-0.25 to 0 °F: 0 days0 to 0.25 °F: 0 days0.25 to 0.5 °F: 0 days0.5 to 0.75 °F: 0 days0.75 to 1 °F: 0 days1 to 1.25 °F: 0 days1.25 to 1.5 °F: 0 days1.5 to 1.75 °F: 0 days1.75 to 2 °F: 0 days2 to 2.25 °F: 0 days2.25 to 2.5 °F: 0 daysdashed: P50 |e| 2.42 · P90 |e| 2.42 °F-2.50+2.5 °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
-2.50-2.251
-2.25-2.000
-2.00-1.750
-1.75-1.500
-1.50-1.250
-1.25-1.000
-1.00-0.750
-0.75-0.500
-0.50-0.250
-0.25+0.000
+0.00+0.250
+0.25+0.500
+0.50+0.750
+0.75+1.000
+1.00+1.250
+1.25+1.500
+1.50+1.750
+1.75+2.000
+2.00+2.250
+2.25+2.500

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-0812.42 -2.42

Availability

ModelScored period DaysCoverage
Pangu-Weather (GFS init)2026-08-30 → 2026-08-30 1
Pangu-Weather (GFS init)2026-08-30 → 2026-08-30 1
Pangu-Weather (GFS init)2026-08-29 → 2026-08-30 2
Pangu-Weather (GFS 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 Pangu-Weather (GFS init) has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 1 +0.20 [0.20, 0.20] yes
Aurora (GFS init) 1 -2.08 [-2.08, -2.08] yes
Aurora (IFS init) 1 +0.96 [0.96, 0.96] yes
FourCastNet v2 (GFS init) 1 +0.68 [0.68, 0.68] yes
FourCastNet v2 (IFS init) 1 +2.29 [2.29, 2.29] yes
NCEP GFS 1 +2.37 [2.37, 2.37] yes
GraphCast (GFS init) 1 -2.01 [-2.01, -2.01] yes
GraphCast (IFS init) 1 -0.34 [-0.34, -0.34] yes
ECMWF IFS HRES 1 +0.34 [0.34, 0.34] yes
Pangu-Weather (IFS init) 1 +0.74 [0.74, 0.74] yes
Persistence (baseline) 1 +1.42 [1.42, 1.42] yes

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSEA (Seattle-Tacoma), model pangu_gfs, 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/KSEA/model/pangu_gfs/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