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

Phoenix Sky Harbor · ECMWF IFS HRES · lead day 1

KPHX · ifs_hres · 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, ifs-gpid161, 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
tmax00Zbilinear30d22 1 QC2.38 [1.62, 3.09]1.66-2.08 [-2.96, -1.08]2.99 [1.95, 3.76]27% [17%, 42%]45%68%+0.25+0.472026-08-02 → 2026-08-30
tmax00Zbilinear90d22 1 QC2.38 [1.39, 3.36]1.66-2.08 [-3.23, -0.88]2.99 [1.75, 3.98]27% [13%, 50%]45%68%+0.25+0.472026-08-02 → 2026-08-30
tmax00Zbilinear365d22 1 QC2.38 [1.30, 3.45]1.66-2.08 [-3.31, -0.79]2.99 [1.62, 4.04]27% [12%, 50%]45%68%+0.25+0.472026-08-02 → 2026-08-30
tmax00Zbilinearall22 1 QC2.38 [1.38, 3.35]1.66-2.08 [-3.24, -0.89]2.99 [1.74, 4.00]27% [14%, 50%]45%68%+0.25+0.472026-08-02 → 2026-08-30
tmax00Znearest30d22 1 QC2.39 [1.64, 3.09]1.63-2.08 [-2.96, -1.09]2.99 [1.96, 3.75]27% [17%, 42%]45%68%+0.25+0.482026-08-02 → 2026-08-30
tmax00Znearest90d22 1 QC2.39 [1.44, 3.39]1.63-2.08 [-3.24, -0.90]2.99 [1.77, 3.97]27% [13%, 50%]45%68%+0.25+0.482026-08-02 → 2026-08-30
tmax00Znearest365d22 1 QC2.39 [1.34, 3.45]1.63-2.08 [-3.36, -0.81]2.99 [1.66, 4.07]27% [12%, 50%]45%68%+0.25+0.482026-08-02 → 2026-08-30
tmax00Znearestall22 1 QC2.39 [1.41, 3.37]1.63-2.08 [-3.22, -0.86]2.99 [1.74, 3.95]27% [14%, 50%]45%68%+0.25+0.482026-08-02 → 2026-08-30
tmax12Zbilinear30d24 1 QC2.99 [1.90, 4.20]2.22-2.82 [-4.15, -1.54]4.02 [2.40, 5.40]29% [12%, 53%]42%62%+0.03+0.282026-08-02 → 2026-08-30
tmax12Zbilinear90d24 1 QC2.99 [1.59, 4.77]2.22-2.82 [-4.65, -1.31]4.02 [2.24, 5.94]29% [12%, 63%]42%62%+0.03+0.282026-08-02 → 2026-08-30
tmax12Zbilinear365d24 1 QC2.99 [1.55, 4.89]2.22-2.82 [-4.88, -1.22]4.02 [2.08, 6.10]29% [11%, 59%]42%62%+0.03+0.282026-08-02 → 2026-08-30
tmax12Zbilinearall24 1 QC2.99 [1.54, 4.96]2.22-2.82 [-4.96, -1.25]4.02 [2.09, 6.20]29% [11%, 62%]42%62%+0.03+0.282026-08-02 → 2026-08-30
tmax12Znearest30d24 1 QC2.92 [1.96, 3.98]2.14-2.68 [-3.87, -1.50]3.89 [2.45, 5.24]29% [12%, 53%]46%58%+0.05+0.302026-08-02 → 2026-08-30
tmax12Znearest90d24 1 QC2.92 [1.68, 4.52]2.14-2.68 [-4.48, -1.26]3.89 [2.28, 5.72]29% [12%, 63%]46%58%+0.05+0.302026-08-02 → 2026-08-30
tmax12Znearest365d24 1 QC2.92 [1.61, 4.57]2.14-2.68 [-4.51, -1.17]3.89 [2.12, 5.91]29% [11%, 59%]46%58%+0.05+0.302026-08-02 → 2026-08-30
tmax12Znearestall24 1 QC2.92 [1.58, 4.65]2.14-2.68 [-4.61, -1.17]3.89 [2.13, 5.97]29% [11%, 62%]46%58%+0.05+0.302026-08-02 → 2026-08-30
tmin00Zbilinear30d22 1 QC3.17 [1.88, 4.47]3.32+0.98 [-0.80, 3.05]4.49 [2.31, 5.97]32% [23%, 44%]55%59%-0.04-0.092026-08-02 → 2026-08-30
tmin00Zbilinear90d22 1 QC3.17 [1.67, 4.43]3.32+0.98 [-0.91, 3.25]4.49 [1.91, 6.03]32% [18%, 50%]55%59%-0.04-0.092026-08-02 → 2026-08-30
tmin00Zbilinear365d22 1 QC3.17 [1.70, 4.41]3.32+0.98 [-1.00, 3.25]4.49 [1.96, 6.00]32% [18%, 50%]55%59%-0.04-0.092026-08-02 → 2026-08-30
tmin00Zbilinearall22 1 QC3.17 [1.45, 4.37]3.32+0.98 [-1.16, 3.50]4.49 [1.64, 5.93]32% [19%, 50%]55%59%-0.04-0.092026-08-02 → 2026-08-30
tmin00Znearest30d22 1 QC3.34 [1.72, 4.88]3.40+1.87 [0.07, 4.00]4.86 [2.29, 6.45]27% [14%, 45%]59%64%-0.10-0.112026-08-02 → 2026-08-30
tmin00Znearest90d22 1 QC3.34 [1.36, 4.96]3.40+1.87 [-0.03, 4.18]4.86 [1.65, 6.58]27% [13%, 50%]59%64%-0.10-0.112026-08-02 → 2026-08-30
tmin00Znearest365d22 1 QC3.34 [1.35, 4.84]3.40+1.87 [-0.07, 4.21]4.86 [1.63, 6.50]27% [14%, 50%]59%64%-0.10-0.112026-08-02 → 2026-08-30
tmin00Znearestall22 1 QC3.34 [1.19, 4.91]3.40+1.87 [-0.21, 4.49]4.86 [1.47, 6.48]27% [14%, 50%]59%64%-0.10-0.112026-08-02 → 2026-08-30
tmin12Zbilinear30d24 1 QC3.42 [2.37, 4.38]3.42+0.50 [-1.35, 2.33]4.47 [2.99, 5.64]21% [9%, 35%]42%54%-0.01-0.012026-08-02 → 2026-08-30
tmin12Zbilinear90d24 1 QC3.42 [2.17, 4.36]3.42+0.50 [-1.60, 2.46]4.47 [2.75, 5.73]21% [7%, 40%]42%54%-0.01-0.012026-08-02 → 2026-08-30
tmin12Zbilinear365d24 1 QC3.42 [2.14, 4.36]3.42+0.50 [-1.69, 2.58]4.47 [2.64, 5.64]21% [6%, 41%]42%54%-0.01-0.012026-08-02 → 2026-08-30
tmin12Zbilinearall24 1 QC3.42 [1.99, 4.33]3.42+0.50 [-1.92, 2.51]4.47 [2.50, 5.57]21% [7%, 44%]42%54%-0.01-0.012026-08-02 → 2026-08-30
tmin12Znearest30d24 1 QC3.50 [2.18, 4.57]3.46+1.29 [-0.63, 3.19]4.67 [2.88, 5.84]21% [6%, 41%]38%62%-0.04-0.032026-08-02 → 2026-08-30
tmin12Znearest90d24 1 QC3.50 [1.91, 4.64]3.46+1.29 [-0.74, 3.30]4.67 [2.56, 5.97]21% [5%, 45%]38%62%-0.04-0.032026-08-02 → 2026-08-30
tmin12Znearest365d24 1 QC3.50 [1.93, 4.62]3.46+1.29 [-0.84, 3.45]4.67 [2.57, 5.91]21% [4%, 44%]38%62%-0.04-0.032026-08-02 → 2026-08-30
tmin12Znearestall24 1 QC3.50 [1.81, 4.63]3.46+1.29 [-1.08, 3.45]4.67 [2.42, 5.85]21% [4%, 50%]38%62%-0.04-0.032026-08-02 → 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 IFS HRES at KPHX, lead day 1, 00Z bilinear tmax+10+50-5-102026-08-02: +0.22 °F2026-08-10: -3.08 °F2026-08-11: -1.58 °F2026-08-12: +0.14 °F2026-08-13: -7.2 °F2026-08-14: -3.74 °F2026-08-15: -2.51 °F2026-08-16: -2.13 °F2026-08-17: -1.69 °F2026-08-18: -2.14 °F2026-08-19: -0.46 °F2026-08-20: +2.17 °F2026-08-21: -0.4 °F2026-08-22: -1.25 °F2026-08-23: -0.67 °F2026-08-24: -3.4 °F2026-08-25: -3.49 °F2026-08-26: -1.91 °F2026-08-27: +0.83 °F2026-08-28: -2.62 °F2026-08-29: -5.85 °F2026-08-30: -4.98 °F2026-08-022026-08-30°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 (29 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-4.98
2026-08-29-5.85
2026-08-28-2.62
2026-08-27+0.83
2026-08-26-1.91
2026-08-25-3.49
2026-08-24-3.40
2026-08-23-0.67
2026-08-22-1.25
2026-08-21-0.40
2026-08-20+2.17
2026-08-19-0.46
2026-08-18-2.14
2026-08-17-1.69
2026-08-16-2.13
2026-08-15-2.51
2026-08-14-3.74
2026-08-13-7.20
2026-08-12+0.14
2026-08-11-1.58
2026-08-10-3.08
2026-08-09—
2026-08-08—
2026-08-07—
2026-08-06—
2026-08-05—
2026-08-04—
2026-08-03—
2026-08-02+0.22

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KPHX, lead day 1-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 1 day-7 to -6 °F: 0 days-6 to -5 °F: 1 day-5 to -4 °F: 1 day-4 to -3 °F: 4 days-3 to -2 °F: 4 days-2 to -1 °F: 4 days-1 to 0 °F: 3 days0 to 1 °F: 3 days1 to 2 °F: 0 days2 to 3 °F: 1 day3 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| 2.13 · P90 |e| 4.86 °F-100+10 °Fn = 22 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
-8.00-7.001
-7.00-6.000
-6.00-5.001
-5.00-4.001
-4.00-3.004
-3.00-2.004
-2.00-1.004
-1.00+0.003
+0.00+1.003
+1.00+2.000
+2.00+3.001
+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
2026-08222.38 -2.08

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-02 → 2026-08-30 22
ECMWF IFS HRES2026-08-02 → 2026-08-30 22
ECMWF IFS HRES2026-08-02 → 2026-08-30 24
ECMWF IFS HRES2026-08-02 → 2026-08-30 24

Compared with other models

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

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 22 -0.90 [-1.85, -0.04] yes
Aurora (GFS init) 1 -9.60 [-9.60, -9.60] yes
Aurora (IFS init) 2 -2.94 [-3.22, -2.66] yes
FourCastNet v2 (GFS init) 1 -7.66 [-7.66, -7.66] yes
FourCastNet v2 (IFS init) 2 -4.92 [-5.72, -4.12] yes
NCEP GFS 22 -0.79 [-2.07, 0.34] no
GraphCast (GFS init) 1 -8.92 [-8.92, -8.92] yes
GraphCast (IFS init) 20 -1.28 [-2.02, -0.68] yes
Pangu-Weather (GFS init) 1 -2.44 [-2.44, -2.44] yes
Pangu-Weather (IFS init) 2 -2.03 [-3.19, -0.87] yes
Persistence (baseline) 22 -0.80 [-2.05, 0.52] no

Cite this page

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

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