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

San Diego Lindbergh · ECMWF AIFS Single · lead day 7

KSAN · aifs_single · lead 7

Target day = initialization date + 7 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, aifs-single-gpid5, starting 2026-08-01 — 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
tmax00Zbilinear30d23 1 QC3.35 [1.97, 4.70]2.18-3.09 [-4.57, -1.52]4.13 [2.39, 5.43]17% [4%, 33%]39%52%+0.11+0.372026-08-08 → 2026-08-30
tmax00Zbilinear90d23 1 QC3.35 [1.82, 4.77]2.18-3.09 [-4.69, -1.38]4.13 [2.23, 5.50]17% [0%, 35%]39%52%+0.11+0.372026-08-08 → 2026-08-30
tmax00Zbilinear365d23 1 QC3.35 [1.69, 4.94]2.18-3.09 [-4.76, -1.29]4.13 [2.10, 5.68]17% [0%, 36%]39%52%+0.11+0.372026-08-08 → 2026-08-30
tmax00Zbilinearall23 1 QC3.35 [1.72, 5.03]2.18-3.09 [-4.94, -1.24]4.13 [2.08, 5.72]17% [0%, 39%]39%52%+0.11+0.372026-08-08 → 2026-08-30
tmax00Znearest30d23 1 QC4.29 [2.68, 5.87]2.24-4.29 [-5.87, -2.68]5.11 [3.32, 6.57]13% [0%, 25%]22%39%-0.15+0.352026-08-08 → 2026-08-30
tmax00Znearest90d23 1 QC4.29 [2.62, 5.95]2.24-4.29 [-5.95, -2.62]5.11 [3.09, 6.65]13% [0%, 25%]22%39%-0.15+0.352026-08-08 → 2026-08-30
tmax00Znearest365d23 1 QC4.29 [2.51, 6.02]2.24-4.29 [-6.02, -2.51]5.11 [3.07, 6.79]13% [0%, 29%]22%39%-0.15+0.352026-08-08 → 2026-08-30
tmax00Znearestall23 1 QC4.29 [2.44, 6.32]2.24-4.29 [-6.32, -2.44]5.11 [2.90, 6.91]13% [0%, 26%]22%39%-0.15+0.352026-08-08 → 2026-08-30
tmax12Zbilinear30d23 1 QC3.91 [2.34, 5.35]2.10-3.91 [-5.35, -2.34]4.79 [2.86, 6.16]13% [0%, 32%]30%43%-0.05+0.392026-08-08 → 2026-08-30
tmax12Zbilinear90d23 1 QC3.91 [2.19, 5.53]2.10-3.91 [-5.53, -2.19]4.79 [2.61, 6.28]13% [0%, 33%]30%43%-0.05+0.392026-08-08 → 2026-08-30
tmax12Zbilinear365d23 1 QC3.91 [2.02, 5.62]2.10-3.91 [-5.62, -2.02]4.79 [2.39, 6.34]13% [0%, 36%]30%43%-0.05+0.392026-08-08 → 2026-08-30
tmax12Zbilinearall23 1 QC3.91 [2.17, 5.64]2.10-3.91 [-5.64, -2.17]4.79 [2.55, 6.40]13% [0%, 32%]30%43%-0.05+0.392026-08-08 → 2026-08-30
tmax12Znearest30d23 1 QC5.15 [3.57, 6.63]2.03-5.15 [-6.63, -3.57]5.82 [3.90, 7.27]0% [0%, 0%]4%17%-0.38+0.412026-08-08 → 2026-08-30
tmax12Znearest90d23 1 QC5.15 [3.51, 6.81]2.03-5.15 [-6.81, -3.51]5.82 [3.82, 7.39]0% [0%, 0%]4%17%-0.38+0.412026-08-08 → 2026-08-30
tmax12Znearest365d23 1 QC5.15 [3.28, 6.88]2.03-5.15 [-6.88, -3.28]5.82 [3.56, 7.48]0% [0%, 0%]4%17%-0.38+0.412026-08-08 → 2026-08-30
tmax12Znearestall23 1 QC5.15 [3.35, 6.94]2.03-5.15 [-6.94, -3.35]5.82 [3.58, 7.53]0% [0%, 0%]4%17%-0.38+0.412026-08-08 → 2026-08-30
tmin00Zbilinear30d23 1 QC0.80 [0.61, 0.98]0.65-0.48 [-0.79, -0.06]1.04 [0.78, 1.26]74% [62%, 86%]91%100%+0.52+0.602026-08-08 → 2026-08-30
tmin00Zbilinear90d23 1 QC0.80 [0.60, 1.00]0.65-0.48 [-0.80, -0.03]1.04 [0.77, 1.29]74% [61%, 89%]91%100%+0.52+0.602026-08-08 → 2026-08-30
tmin00Zbilinear365d23 1 QC0.80 [0.57, 1.00]0.65-0.48 [-0.81, 0.03]1.04 [0.75, 1.28]74% [61%, 90%]91%100%+0.52+0.602026-08-08 → 2026-08-30
tmin00Zbilinearall23 1 QC0.80 [0.57, 1.00]0.65-0.48 [-0.83, -0.01]1.04 [0.75, 1.30]74% [60%, 90%]91%100%+0.52+0.602026-08-08 → 2026-08-30
tmin00Znearest30d23 1 QC0.82 [0.58, 1.03]0.67-0.55 [-0.87, -0.17]1.07 [0.78, 1.31]65% [45%, 80%]91%100%+0.51+0.582026-08-08 → 2026-08-30
tmin00Znearest90d23 1 QC0.82 [0.56, 1.04]0.67-0.55 [-0.90, -0.16]1.07 [0.75, 1.32]65% [43%, 81%]91%100%+0.51+0.582026-08-08 → 2026-08-30
tmin00Znearest365d23 1 QC0.82 [0.53, 1.05]0.67-0.55 [-0.91, -0.13]1.07 [0.71, 1.32]65% [43%, 86%]91%100%+0.51+0.582026-08-08 → 2026-08-30
tmin00Znearestall23 1 QC0.82 [0.53, 1.05]0.67-0.55 [-0.97, -0.15]1.07 [0.69, 1.33]65% [43%, 81%]91%100%+0.51+0.582026-08-08 → 2026-08-30
tmin12Zbilinear30d23 1 QC1.01 [0.70, 1.36]0.78-0.95 [-1.34, -0.58]1.29 [0.98, 1.58]57% [38%, 74%]78%100%+0.39+0.522026-08-08 → 2026-08-30
tmin12Zbilinear90d23 1 QC1.01 [0.68, 1.42]0.78-0.95 [-1.42, -0.51]1.29 [0.97, 1.60]57% [33%, 75%]78%100%+0.39+0.522026-08-08 → 2026-08-30
tmin12Zbilinear365d23 1 QC1.01 [0.68, 1.43]0.78-0.95 [-1.42, -0.52]1.29 [0.98, 1.61]57% [33%, 75%]78%100%+0.39+0.522026-08-08 → 2026-08-30
tmin12Zbilinearall23 1 QC1.01 [0.68, 1.45]0.78-0.95 [-1.44, -0.52]1.29 [0.97, 1.63]57% [31%, 75%]78%100%+0.39+0.522026-08-08 → 2026-08-30
tmin12Znearest30d23 1 QC1.09 [0.84, 1.38]0.72-1.09 [-1.38, -0.84]1.35 [1.08, 1.61]57% [38%, 74%]91%100%+0.34+0.562026-08-08 → 2026-08-30
tmin12Znearest90d23 1 QC1.09 [0.82, 1.45]0.72-1.09 [-1.45, -0.82]1.35 [1.07, 1.66]57% [33%, 75%]91%100%+0.34+0.562026-08-08 → 2026-08-30
tmin12Znearest365d23 1 QC1.09 [0.83, 1.47]0.72-1.09 [-1.47, -0.83]1.35 [1.07, 1.68]57% [33%, 75%]91%100%+0.34+0.562026-08-08 → 2026-08-30
tmin12Znearestall23 1 QC1.09 [0.83, 1.48]0.72-1.09 [-1.48, -0.83]1.35 [1.07, 1.70]57% [31%, 75%]91%100%+0.34+0.562026-08-08 → 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 ECMWF AIFS Single at KSAN, lead day 7, 00Z bilinear tmax+20+100-10-202026-08-08: -3.95 °F2026-08-09: -4.45 °F2026-08-10: -5.4 °F2026-08-11: -3.77 °F2026-08-12: -4.17 °F2026-08-13: -1.62 °F2026-08-14: -2.28 °F2026-08-15: -1.68 °F2026-08-16: -0.77 °F2026-08-17: +0.51 °F2026-08-18: +1.37 °F2026-08-19: -1.62 °F2026-08-20: -2.3 °F2026-08-21: -4.83 °F2026-08-22: -3.37 °F2026-08-23: -10.63 °F2026-08-24: -5.86 °F2026-08-25: -5.97 °F2026-08-26: -6.63 °F2026-08-27: +0.97 °F2026-08-28: -1.77 °F2026-08-29: -2.88 °F2026-08-30: +0.13 °F2026-08-082026-08-30°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 (23 days, newest first) · download CSV
Climatological dayError °F
2026-08-30+0.13
2026-08-29-2.88
2026-08-28-1.77
2026-08-27+0.97
2026-08-26-6.63
2026-08-25-5.97
2026-08-24-5.86
2026-08-23-10.63
2026-08-22-3.37
2026-08-21-4.83
2026-08-20-2.30
2026-08-19-1.62
2026-08-18+1.37
2026-08-17+0.51
2026-08-16-0.77
2026-08-15-1.68
2026-08-14-2.28
2026-08-13-1.62
2026-08-12-4.17
2026-08-11-3.77
2026-08-10-5.40
2026-08-09-4.45
2026-08-08-3.95

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KSAN, lead day 7-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 0 days-12 to -10 °F: 1 day-10 to -8 °F: 0 days-8 to -6 °F: 1 day-6 to -4 °F: 6 days-4 to -2 °F: 6 days-2 to 0 °F: 5 days0 to 2 °F: 4 days2 to 4 °F: 0 days4 to 6 °F: 0 days6 to 8 °F: 0 days8 to 10 °F: 0 days10 to 12 °F: 0 days12 to 14 °F: 0 days14 to 16 °F: 0 days16 to 18 °F: 0 days18 to 20 °F: 0 daysdashed: P50 |e| 2.88 · P90 |e| 5.95 °F-200+20 °Fn = 23 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
-20.00-18.000
-18.00-16.000
-16.00-14.000
-14.00-12.000
-12.00-10.001
-10.00-8.000
-8.00-6.001
-6.00-4.006
-4.00-2.006
-2.00+0.005
+0.00+2.004
+2.00+4.000
+4.00+6.000
+6.00+8.000
+8.00+10.000
+10.00+12.000
+12.00+14.000
+14.00+16.000
+16.00+18.000
+18.00+20.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08233.35 -3.09

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-08 → 2026-08-30 23
ECMWF AIFS Single2026-08-08 → 2026-08-30 23
ECMWF AIFS Single2026-08-08 → 2026-08-30 23
ECMWF AIFS Single2026-08-08 → 2026-08-30 23

Compared with other models

Paired bootstrap on the days both models cover (90d, 00Z, bilinear, daily maximum). Negative means ECMWF AIFS Single has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
NCEP GFS 23 -0.38 [-1.47, 0.37] no
GraphCast (IFS init) 23 -2.36 [-3.54, -1.18] yes
ECMWF IFS HRES 18 -2.28 [-3.34, -1.17] yes
Persistence (baseline) 23 -0.39 [-1.94, 1.29] no

Cite this page

ShortCastCheck, KSAN aifs_single lead 7, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KSAN/model/aifs_single/lead/7/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSAN (San Diego Lindbergh), model aifs_single, lead day 7. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KSAN/model/aifs_single/lead/7/

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