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

San Diego Lindbergh · ECMWF AIFS Single · lead day 5

KSAN · aifs_single · lead 5

Target day = initialization date + 5 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
tmax00Zbilinear30d25 1 QC3.48 [2.19, 4.67]2.00-3.38 [-4.66, -1.94]4.24 [2.81, 5.42]20% [0%, 43%]36%44%-0.14+0.302026-08-06 → 2026-08-30
tmax00Zbilinear90d25 1 QC3.48 [2.10, 4.73]2.00-3.38 [-4.73, -1.85]4.24 [2.66, 5.46]20% [0%, 43%]36%44%-0.14+0.302026-08-06 → 2026-08-30
tmax00Zbilinear365d25 1 QC3.48 [1.90, 4.89]2.00-3.38 [-4.89, -1.66]4.24 [2.54, 5.58]20% [0%, 44%]36%44%-0.14+0.302026-08-06 → 2026-08-30
tmax00Zbilinearall25 1 QC3.48 [1.89, 5.04]2.00-3.38 [-5.04, -1.65]4.24 [2.47, 5.67]20% [0%, 43%]36%44%-0.14+0.302026-08-06 → 2026-08-30
tmax00Znearest30d25 1 QC4.66 [3.16, 6.05]2.03-4.66 [-6.05, -3.16]5.33 [3.77, 6.62]4% [0%, 12%]16%32%-0.53+0.292026-08-06 → 2026-08-30
tmax00Znearest90d25 1 QC4.66 [3.06, 6.05]2.03-4.66 [-6.05, -3.06]5.33 [3.57, 6.64]4% [0%, 11%]16%32%-0.53+0.292026-08-06 → 2026-08-30
tmax00Znearest365d25 1 QC4.66 [2.90, 6.23]2.03-4.66 [-6.23, -2.90]5.33 [3.45, 6.77]4% [0%, 12%]16%32%-0.53+0.292026-08-06 → 2026-08-30
tmax00Znearestall25 1 QC4.66 [2.85, 6.38]2.03-4.66 [-6.38, -2.85]5.33 [3.34, 6.87]4% [0%, 12%]16%32%-0.53+0.292026-08-06 → 2026-08-30
tmax12Zbilinear30d24 1 QC3.84 [2.67, 4.89]1.83-3.83 [-4.89, -2.65]4.44 [3.27, 5.35]12% [0%, 31%]29%38%-0.26+0.362026-08-06 → 2026-08-30
tmax12Zbilinear90d24 1 QC3.84 [2.58, 4.95]1.83-3.83 [-4.95, -2.56]4.44 [3.14, 5.38]12% [0%, 32%]29%38%-0.26+0.362026-08-06 → 2026-08-30
tmax12Zbilinear365d24 1 QC3.84 [2.50, 5.03]1.83-3.83 [-5.03, -2.48]4.44 [3.07, 5.48]12% [0%, 33%]29%38%-0.26+0.362026-08-06 → 2026-08-30
tmax12Zbilinearall24 1 QC3.84 [2.48, 5.15]1.83-3.83 [-5.15, -2.46]4.44 [3.03, 5.57]12% [0%, 30%]29%38%-0.26+0.362026-08-06 → 2026-08-30
tmax12Znearest30d24 1 QC5.14 [3.88, 6.30]1.88-5.14 [-6.30, -3.88]5.63 [4.26, 6.68]0% [0%, 0%]4%21%-0.69+0.352026-08-06 → 2026-08-30
tmax12Znearest90d24 1 QC5.14 [3.77, 6.36]1.88-5.14 [-6.36, -3.77]5.63 [4.14, 6.73]0% [0%, 0%]4%21%-0.69+0.352026-08-06 → 2026-08-30
tmax12Znearest365d24 1 QC5.14 [3.69, 6.44]1.88-5.14 [-6.44, -3.69]5.63 [4.05, 6.83]0% [0%, 0%]4%21%-0.69+0.352026-08-06 → 2026-08-30
tmax12Znearestall24 1 QC5.14 [3.67, 6.57]1.88-5.14 [-6.57, -3.67]5.63 [4.01, 6.95]0% [0%, 0%]4%21%-0.69+0.352026-08-06 → 2026-08-30
tmin00Zbilinear30d25 1 QC0.82 [0.59, 1.18]0.63-0.66 [-1.05, -0.34]1.00 [0.76, 1.35]56% [28%, 77%]96%100%+0.46+0.542026-08-06 → 2026-08-30
tmin00Zbilinear90d25 1 QC0.82 [0.58, 1.31]0.63-0.66 [-1.14, -0.30]1.00 [0.74, 1.42]56% [22%, 79%]96%100%+0.46+0.542026-08-06 → 2026-08-30
tmin00Zbilinear365d25 1 QC0.82 [0.57, 1.31]0.63-0.66 [-1.14, -0.25]1.00 [0.73, 1.41]56% [23%, 81%]96%100%+0.46+0.542026-08-06 → 2026-08-30
tmin00Zbilinearall25 1 QC0.82 [0.58, 1.31]0.63-0.66 [-1.14, -0.28]1.00 [0.74, 1.43]56% [21%, 80%]96%100%+0.46+0.542026-08-06 → 2026-08-30
tmin00Znearest30d25 1 QC0.91 [0.65, 1.30]0.61-0.82 [-1.24, -0.54]1.09 [0.79, 1.48]52% [30%, 73%]92%100%+0.40+0.562026-08-06 → 2026-08-30
tmin00Znearest90d25 1 QC0.91 [0.65, 1.42]0.61-0.82 [-1.36, -0.54]1.09 [0.79, 1.60]52% [23%, 75%]92%100%+0.40+0.562026-08-06 → 2026-08-30
tmin00Znearest365d25 1 QC0.91 [0.63, 1.41]0.61-0.82 [-1.34, -0.51]1.09 [0.76, 1.59]52% [23%, 75%]92%100%+0.40+0.562026-08-06 → 2026-08-30
tmin00Znearestall25 1 QC0.91 [0.64, 1.45]0.61-0.82 [-1.39, -0.52]1.09 [0.78, 1.60]52% [24%, 75%]92%100%+0.40+0.562026-08-06 → 2026-08-30
tmin12Zbilinear30d24 1 QC1.25 [0.92, 1.77]0.75-1.13 [-1.73, -0.67]1.47 [1.08, 1.99]42% [22%, 58%]92%96%+0.14+0.452026-08-06 → 2026-08-30
tmin12Zbilinear90d24 1 QC1.25 [0.90, 1.91]0.75-1.13 [-1.91, -0.61]1.47 [1.05, 2.17]42% [18%, 60%]92%96%+0.14+0.452026-08-06 → 2026-08-30
tmin12Zbilinear365d24 1 QC1.25 [0.85, 1.91]0.75-1.13 [-1.91, -0.55]1.47 [0.99, 2.11]42% [20%, 62%]92%96%+0.14+0.452026-08-06 → 2026-08-30
tmin12Zbilinearall24 1 QC1.25 [0.85, 1.92]0.75-1.13 [-1.91, -0.58]1.47 [1.00, 2.14]42% [18%, 60%]92%96%+0.14+0.452026-08-06 → 2026-08-30
tmin12Znearest30d24 1 QC1.32 [1.01, 1.85]0.67-1.30 [-1.85, -0.97]1.55 [1.18, 2.13]38% [21%, 55%]83%96%+0.09+0.512026-08-06 → 2026-08-30
tmin12Znearest90d24 1 QC1.32 [0.98, 2.09]0.67-1.30 [-2.09, -0.94]1.55 [1.17, 2.32]38% [18%, 57%]83%96%+0.09+0.512026-08-06 → 2026-08-30
tmin12Znearest365d24 1 QC1.32 [0.97, 2.02]0.67-1.30 [-2.02, -0.92]1.55 [1.15, 2.21]38% [20%, 58%]83%96%+0.09+0.512026-08-06 → 2026-08-30
tmin12Znearestall24 1 QC1.32 [0.98, 2.11]0.67-1.30 [-2.10, -0.94]1.55 [1.16, 2.28]38% [18%, 57%]83%96%+0.09+0.512026-08-06 → 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 5, 00Z bilinear tmax+10+50-5-102026-08-06: -3.47 °F2026-08-07: -3.76 °F2026-08-08: -3.37 °F2026-08-09: -4.61 °F2026-08-10: -4.96 °F2026-08-11: -4.33 °F2026-08-12: -3.93 °F2026-08-13: -1.66 °F2026-08-14: -2.6 °F2026-08-15: -1.43 °F2026-08-16: -0.53 °F2026-08-17: +0.31 °F2026-08-18: +0.92 °F2026-08-19: -0.3 °F2026-08-20: -2.83 °F2026-08-21: -5.31 °F2026-08-22: -5.4 °F2026-08-23: -9.54 °F2026-08-24: -3.33 °F2026-08-25: -5.56 °F2026-08-26: -9.07 °F2026-08-27: -0.7 °F2026-08-28: -1.95 °F2026-08-29: -5.72 °F2026-08-30: -1.43 °F2026-08-062026-08-30°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 (25 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-1.43
2026-08-29-5.72
2026-08-28-1.95
2026-08-27-0.70
2026-08-26-9.07
2026-08-25-5.56
2026-08-24-3.33
2026-08-23-9.54
2026-08-22-5.40
2026-08-21-5.31
2026-08-20-2.83
2026-08-19-0.30
2026-08-18+0.92
2026-08-17+0.31
2026-08-16-0.53
2026-08-15-1.43
2026-08-14-2.60
2026-08-13-1.66
2026-08-12-3.93
2026-08-11-4.33
2026-08-10-4.96
2026-08-09-4.61
2026-08-08-3.37
2026-08-07-3.76
2026-08-06-3.47

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KSAN, lead day 5-10 to -9 °F: 2 days-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 0 days-6 to -5 °F: 4 days-5 to -4 °F: 3 days-4 to -3 °F: 5 days-3 to -2 °F: 2 days-2 to -1 °F: 4 days-1 to 0 °F: 3 days0 to 1 °F: 2 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| 3.37 · P90 |e| 5.65 °F-100+10 °Fn = 25 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
-10.00-9.002
-9.00-8.000
-8.00-7.000
-7.00-6.000
-6.00-5.004
-5.00-4.003
-4.00-3.005
-3.00-2.002
-2.00-1.004
-1.00+0.003
+0.00+1.002
+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
2026-08253.48 -3.38

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-06 → 2026-08-30 25
ECMWF AIFS Single2026-08-06 → 2026-08-30 25
ECMWF AIFS Single2026-08-06 → 2026-08-30 24
ECMWF AIFS Single2026-08-06 → 2026-08-30 24

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 25 +0.16 [-0.73, 1.13] no
GraphCast (IFS init) 25 -2.12 [-2.90, -1.43] yes
ECMWF IFS HRES 18 -2.32 [-3.32, -1.39] yes
Persistence (baseline) 25 +0.44 [-0.76, 1.69] no

Cite this page

ShortCastCheck, KSAN aifs_single lead 5, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KSAN/model/aifs_single/lead/5/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KSAN (San Diego Lindbergh), model aifs_single, lead day 5. 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/5/

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