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

Phoenix Sky Harbor · ECMWF AIFS Single · lead day 5

KPHX · 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 QC4.14 [3.19, 5.29]2.70-3.54 [-5.09, -2.14]4.93 [3.73, 6.08]4% [0%, 12%]20%48%+0.24+0.502026-08-06 → 2026-08-30
tmax00Zbilinear90d25 1 QC4.14 [3.15, 5.43]2.70-3.54 [-5.41, -2.08]4.93 [3.59, 6.23]4% [0%, 12%]20%48%+0.24+0.502026-08-06 → 2026-08-30
tmax00Zbilinear365d25 1 QC4.14 [3.03, 5.63]2.70-3.54 [-5.62, -1.94]4.93 [3.33, 6.41]4% [0%, 14%]20%48%+0.24+0.502026-08-06 → 2026-08-30
tmax00Zbilinearall25 1 QC4.14 [3.07, 5.61]2.70-3.54 [-5.52, -2.04]4.93 [3.53, 6.34]4% [0%, 13%]20%48%+0.24+0.502026-08-06 → 2026-08-30
tmax00Znearest30d25 1 QC4.11 [3.18, 5.25]2.68-3.51 [-5.05, -2.13]4.90 [3.70, 6.04]4% [0%, 12%]24%48%+0.24+0.512026-08-06 → 2026-08-30
tmax00Znearest90d25 1 QC4.11 [3.12, 5.39]2.68-3.51 [-5.37, -2.08]4.90 [3.55, 6.22]4% [0%, 12%]24%48%+0.24+0.512026-08-06 → 2026-08-30
tmax00Znearest365d25 1 QC4.11 [3.01, 5.60]2.68-3.51 [-5.58, -1.94]4.90 [3.30, 6.37]4% [0%, 14%]24%48%+0.24+0.512026-08-06 → 2026-08-30
tmax00Znearestall25 1 QC4.11 [3.05, 5.57]2.68-3.51 [-5.48, -2.05]4.90 [3.49, 6.32]4% [0%, 13%]24%48%+0.24+0.512026-08-06 → 2026-08-30
tmax12Zbilinear30d24 1 QC4.64 [3.48, 6.36]2.81-4.38 [-6.33, -2.98]5.70 [4.37, 7.41]8% [0%, 22%]25%42%+0.16+0.492026-08-06 → 2026-08-30
tmax12Zbilinear90d24 1 QC4.64 [3.40, 6.79]2.81-4.38 [-6.79, -2.95]5.70 [4.21, 7.81]8% [0%, 22%]25%42%+0.16+0.492026-08-06 → 2026-08-30
tmax12Zbilinear365d24 1 QC4.64 [3.28, 6.70]2.81-4.38 [-6.70, -2.76]5.70 [4.10, 7.73]8% [0%, 25%]25%42%+0.16+0.492026-08-06 → 2026-08-30
tmax12Zbilinearall24 1 QC4.64 [3.41, 6.98]2.81-4.38 [-6.89, -2.92]5.70 [4.22, 8.01]8% [0%, 22%]25%42%+0.16+0.492026-08-06 → 2026-08-30
tmax12Znearest30d24 1 QC4.60 [3.44, 6.32]2.78-4.35 [-6.29, -2.96]5.65 [4.32, 7.37]8% [0%, 22%]25%42%+0.17+0.502026-08-06 → 2026-08-30
tmax12Znearest90d24 1 QC4.60 [3.36, 6.72]2.78-4.35 [-6.72, -2.94]5.65 [4.17, 7.78]8% [0%, 22%]25%42%+0.17+0.502026-08-06 → 2026-08-30
tmax12Znearest365d24 1 QC4.60 [3.24, 6.65]2.78-4.35 [-6.65, -2.76]5.65 [4.05, 7.69]8% [0%, 25%]25%42%+0.17+0.502026-08-06 → 2026-08-30
tmax12Znearestall24 1 QC4.60 [3.36, 6.94]2.78-4.35 [-6.85, -2.90]5.65 [4.17, 7.97]8% [0%, 22%]25%42%+0.17+0.502026-08-06 → 2026-08-30
tmin00Zbilinear30d25 1 QC4.01 [2.84, 5.26]3.35-2.02 [-4.12, -0.36]4.87 [3.67, 6.03]12% [4%, 20%]28%48%+0.28+0.402026-08-06 → 2026-08-30
tmin00Zbilinear90d25 1 QC4.01 [2.70, 5.32]3.35-2.02 [-4.41, -0.17]4.87 [3.45, 6.03]12% [0%, 21%]28%48%+0.28+0.402026-08-06 → 2026-08-30
tmin00Zbilinear365d25 1 QC4.01 [2.63, 5.38]3.35-2.02 [-4.50, -0.04]4.87 [3.35, 6.09]12% [0%, 21%]28%48%+0.28+0.402026-08-06 → 2026-08-30
tmin00Zbilinearall25 1 QC4.01 [2.67, 5.26]3.35-2.02 [-4.36, -0.16]4.87 [3.45, 5.91]12% [0%, 21%]28%48%+0.28+0.402026-08-06 → 2026-08-30
tmin00Znearest30d25 1 QC4.06 [2.88, 5.30]3.39-2.07 [-4.19, -0.41]4.92 [3.69, 6.05]12% [4%, 20%]32%48%+0.27+0.392026-08-06 → 2026-08-30
tmin00Znearest90d25 1 QC4.06 [2.75, 5.37]3.39-2.07 [-4.48, -0.22]4.92 [3.49, 6.06]12% [0%, 21%]32%48%+0.27+0.392026-08-06 → 2026-08-30
tmin00Znearest365d25 1 QC4.06 [2.65, 5.44]3.39-2.07 [-4.59, -0.13]4.92 [3.39, 6.13]12% [0%, 21%]32%48%+0.27+0.392026-08-06 → 2026-08-30
tmin00Znearestall25 1 QC4.06 [2.73, 5.33]3.39-2.07 [-4.42, -0.17]4.92 [3.49, 5.94]12% [0%, 21%]32%48%+0.27+0.392026-08-06 → 2026-08-30
tmin12Zbilinear30d24 1 QC4.23 [3.20, 5.43]3.44-2.19 [-4.16, -0.35]5.01 [3.92, 6.15]8% [0%, 17%]29%42%+0.24+0.392026-08-06 → 2026-08-30
tmin12Zbilinear90d24 1 QC4.23 [3.07, 5.55]3.44-2.19 [-4.40, -0.27]5.01 [3.63, 6.18]8% [0%, 17%]29%42%+0.24+0.392026-08-06 → 2026-08-30
tmin12Zbilinear365d24 1 QC4.23 [3.01, 5.59]3.44-2.19 [-4.48, -0.12]5.01 [3.60, 6.26]8% [0%, 17%]29%42%+0.24+0.392026-08-06 → 2026-08-30
tmin12Zbilinearall24 1 QC4.23 [3.05, 5.44]3.44-2.19 [-4.46, -0.15]5.01 [3.64, 6.09]8% [0%, 17%]29%42%+0.24+0.392026-08-06 → 2026-08-30
tmin12Znearest30d24 1 QC4.26 [3.22, 5.45]3.45-2.23 [-4.19, -0.38]5.04 [3.94, 6.17]8% [0%, 17%]29%42%+0.24+0.382026-08-06 → 2026-08-30
tmin12Znearest90d24 1 QC4.26 [3.09, 5.56]3.45-2.23 [-4.41, -0.32]5.04 [3.64, 6.20]8% [0%, 17%]29%42%+0.24+0.382026-08-06 → 2026-08-30
tmin12Znearest365d24 1 QC4.26 [3.02, 5.61]3.45-2.23 [-4.54, -0.16]5.04 [3.59, 6.28]8% [0%, 17%]29%42%+0.24+0.382026-08-06 → 2026-08-30
tmin12Znearestall24 1 QC4.26 [3.06, 5.47]3.45-2.23 [-4.48, -0.18]5.04 [3.62, 6.12]8% [0%, 17%]29%42%+0.24+0.382026-08-06 → 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 KPHX, lead day 5, 00Z bilinear tmax+20+100-10-202026-08-06: -3.66 °F2026-08-07: -4.12 °F2026-08-08: -4.17 °F2026-08-09: -1.26 °F2026-08-10: -2.58 °F2026-08-11: -2.12 °F2026-08-12: -10.09 °F2026-08-13: -1.46 °F2026-08-14: +2.62 °F2026-08-15: -2.36 °F2026-08-16: -3.06 °F2026-08-17: -2.71 °F2026-08-18: -2.76 °F2026-08-19: +1.8 °F2026-08-20: +3.07 °F2026-08-21: -4.11 °F2026-08-22: -7.03 °F2026-08-23: -8.91 °F2026-08-24: -1.83 °F2026-08-25: -6.62 °F2026-08-26: -6.85 °F2026-08-27: -0.52 °F2026-08-28: -2.62 °F2026-08-29: -9.4 °F2026-08-30: -7.73 °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
2026-08-30-7.73
2026-08-29-9.40
2026-08-28-2.62
2026-08-27-0.52
2026-08-26-6.85
2026-08-25-6.62
2026-08-24-1.83
2026-08-23-8.91
2026-08-22-7.03
2026-08-21-4.11
2026-08-20+3.07
2026-08-19+1.80
2026-08-18-2.76
2026-08-17-2.71
2026-08-16-3.06
2026-08-15-2.36
2026-08-14+2.62
2026-08-13-1.46
2026-08-12-10.09
2026-08-11-2.12
2026-08-10-2.58
2026-08-09-1.26
2026-08-08-4.17
2026-08-07-4.12
2026-08-06-3.66

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KPHX, lead day 5-20 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: 2 days-8 to -6 °F: 4 days-6 to -4 °F: 3 days-4 to -2 °F: 8 days-2 to 0 °F: 4 days0 to 2 °F: 1 day2 to 4 °F: 2 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| 3.06 · P90 |e| 8.44 °F-200+20 °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
-20.00-18.000
-18.00-16.000
-16.00-14.000
-14.00-12.000
-12.00-10.001
-10.00-8.002
-8.00-6.004
-6.00-4.003
-4.00-2.008
-2.00+0.004
+0.00+2.001
+2.00+4.002
+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
2026-08254.14 -3.54

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 +0.12 [-1.25, 2.08] no
GraphCast (IFS init) 25 -0.92 [-2.04, 0.32] no
ECMWF IFS HRES 18 +1.14 [0.07, 2.06] yes
Persistence (baseline) 25 -1.30 [-3.83, 1.35] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KPHX (Phoenix Sky Harbor), 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/KPHX/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