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

Phoenix Sky Harbor · ECMWF IFS HRES · lead day 0

KPHX · ifs_hres · lead 0

Target day = initialization date + 0 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, 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
tmax00Zbilinear30d25 1 QC2.09 [1.34, 3.11]1.49-2.01 [-3.04, -1.11]3.12 [1.65, 4.73]40% [24%, 64%]60%84%——2026-08-01 → 2026-08-30
tmax00Zbilinear90d25 1 QC2.09 [1.10, 3.59]1.49-2.01 [-3.59, -0.81]3.12 [1.40, 5.26]40% [22%, 75%]60%84%——2026-08-01 → 2026-08-30
tmax00Zbilinear365d25 1 QC2.09 [1.13, 3.71]1.49-2.01 [-3.62, -0.82]3.12 [1.43, 5.55]40% [20%, 70%]60%84%——2026-08-01 → 2026-08-30
tmax00Zbilinearall25 1 QC2.09 [1.06, 3.79]1.49-2.01 [-3.72, -0.81]3.12 [1.33, 5.64]40% [22%, 75%]60%84%——2026-08-01 → 2026-08-30
tmax00Znearest30d25 1 QC1.98 [1.24, 3.05]1.48-1.89 [-3.00, -1.00]3.04 [1.60, 4.72]40% [26%, 55%]64%84%——2026-08-01 → 2026-08-30
tmax00Znearest90d25 1 QC1.98 [0.97, 3.52]1.48-1.89 [-3.51, -0.73]3.04 [1.35, 5.24]40% [23%, 62%]64%84%——2026-08-01 → 2026-08-30
tmax00Znearest365d25 1 QC1.98 [1.04, 3.71]1.48-1.89 [-3.57, -0.75]3.04 [1.41, 5.55]40% [22%, 60%]64%84%——2026-08-01 → 2026-08-30
tmax00Znearestall25 1 QC1.98 [0.98, 3.79]1.48-1.89 [-3.69, -0.65]3.04 [1.32, 5.64]40% [22%, 61%]64%84%——2026-08-01 → 2026-08-30
tmin00Zbilinear30d25 1 QC3.15 [2.19, 4.06]3.23+0.29 [-1.45, 1.87]4.21 [2.86, 5.43]20% [9%, 33%]36%68%——2026-08-01 → 2026-08-30
tmin00Zbilinear90d25 1 QC3.15 [2.06, 4.11]3.23+0.29 [-1.70, 1.98]4.21 [2.62, 5.51]20% [7%, 35%]36%68%——2026-08-01 → 2026-08-30
tmin00Zbilinear365d25 1 QC3.15 [1.98, 4.11]3.23+0.29 [-1.67, 1.87]4.21 [2.53, 5.49]20% [7%, 33%]36%68%——2026-08-01 → 2026-08-30
tmin00Zbilinearall25 1 QC3.15 [2.04, 4.10]3.23+0.29 [-2.04, 2.02]4.21 [2.52, 5.47]20% [7%, 36%]36%68%——2026-08-01 → 2026-08-30
tmin00Znearest30d25 1 QC3.04 [2.02, 3.99]3.20+1.18 [-0.62, 2.84]4.37 [2.73, 5.76]24% [11%, 38%]48%72%——2026-08-01 → 2026-08-30
tmin00Znearest90d25 1 QC3.04 [1.85, 4.11]3.20+1.18 [-0.90, 2.92]4.37 [2.43, 5.86]24% [8%, 38%]48%72%——2026-08-01 → 2026-08-30
tmin00Znearest365d25 1 QC3.04 [1.77, 4.10]3.20+1.18 [-0.89, 2.83]4.37 [2.30, 5.79]24% [9%, 38%]48%72%——2026-08-01 → 2026-08-30
tmin00Znearestall25 1 QC3.04 [1.70, 4.11]3.20+1.18 [-1.23, 2.92]4.37 [2.05, 5.75]24% [7%, 38%]48%72%——2026-08-01 → 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 0, 00Z bilinear tmax+20+100-10-202026-08-01: -0.81 °F2026-08-06: +0.88 °F2026-08-08: +0.14 °F2026-08-09: -0.13 °F2026-08-10: -2.18 °F2026-08-11: -0.95 °F2026-08-12: -0.67 °F2026-08-13: -4.86 °F2026-08-14: -1.45 °F2026-08-15: -3.5 °F2026-08-16: -1.47 °F2026-08-17: -2.01 °F2026-08-18: -2.41 °F2026-08-19: -1 °F2026-08-20: -0.68 °F2026-08-21: -2.23 °F2026-08-22: -2.53 °F2026-08-23: -0.44 °F2026-08-24: -1.09 °F2026-08-25: -2.96 °F2026-08-26: -1.56 °F2026-08-27: -0.6 °F2026-08-28: -1.69 °F2026-08-29: -4.08 °F2026-08-30: -11.86 °F2026-08-012026-08-30°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 (30 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-11.86
2026-08-29-4.08
2026-08-28-1.69
2026-08-27-0.60
2026-08-26-1.56
2026-08-25-2.96
2026-08-24-1.09
2026-08-23-0.44
2026-08-22-2.53
2026-08-21-2.23
2026-08-20-0.68
2026-08-19-1.00
2026-08-18-2.41
2026-08-17-2.01
2026-08-16-1.47
2026-08-15-3.50
2026-08-14-1.45
2026-08-13-4.86
2026-08-12-0.67
2026-08-11-0.95
2026-08-10-2.18
2026-08-09-0.13
2026-08-08+0.14
2026-08-07—
2026-08-06+0.88
2026-08-05—
2026-08-04—
2026-08-03—
2026-08-02—
2026-08-01-0.81

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KPHX, lead day 0-20 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: 0 days-6 to -4 °F: 2 days-4 to -2 °F: 7 days-2 to 0 °F: 13 days0 to 2 °F: 2 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| 1.47 · P90 |e| 3.85 °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
-10.00-8.000
-8.00-6.000
-6.00-4.002
-4.00-2.007
-2.00+0.0013
+0.00+2.002
+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
2026-08252.09 -2.01

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-01 → 2026-08-30 25
ECMWF IFS HRES2026-08-01 → 2026-08-30 25

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 25 -1.14 [-1.72, -0.54] yes
Aurora (GFS init) 2 -5.47 [-10.10, -0.83] yes
Aurora (IFS init) 3 +0.16 [-1.88, 4.26] no
FourCastNet v2 (GFS init) 2 -2.60 [-6.70, 1.50] no
FourCastNet v2 (IFS init) 3 -2.07 [-3.88, 1.55] no
NCEP GFS 25 -1.04 [-1.83, -0.23] yes
GraphCast (GFS init) 2 -6.92 [-10.42, -3.41] yes
GraphCast (IFS init) 23 -0.90 [-1.44, -0.14] yes
Pangu-Weather (GFS init) 2 -0.78 [-4.61, 3.05] no
Pangu-Weather (IFS init) 3 -0.22 [-2.95, 5.23] no

Cite this page

ShortCastCheck, KPHX ifs_hres lead 0, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KPHX/model/ifs_hres/lead/0/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KPHX (Phoenix Sky Harbor), model ifs_hres, lead day 0. 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/0/

Accessed2026-08-31 (data through 2026-08-30; page built 2026-08-31T03:52:06+00:00)

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