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

Phoenix Sky Harbor · ECMWF AIFS Single · lead day 7

KPHX · 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 QC5.51 [3.57, 7.47]3.93-5.14 [-7.14, -2.91]7.01 [4.65, 8.97]13% [0%, 24%]26%35%-0.03+0.272026-08-08 → 2026-08-30
tmax00Zbilinear90d23 1 QC5.51 [3.30, 7.48]3.93-5.14 [-7.21, -2.60]7.01 [4.30, 8.85]13% [0%, 25%]26%35%-0.03+0.272026-08-08 → 2026-08-30
tmax00Zbilinear365d23 1 QC5.51 [3.26, 7.77]3.93-5.14 [-7.46, -2.42]7.01 [4.18, 9.17]13% [0%, 29%]26%35%-0.03+0.272026-08-08 → 2026-08-30
tmax00Zbilinearall23 1 QC5.51 [3.48, 7.80]3.93-5.14 [-7.46, -2.76]7.01 [4.57, 9.37]13% [0%, 27%]26%35%-0.03+0.272026-08-08 → 2026-08-30
tmax00Znearest30d23 1 QC5.52 [3.60, 7.46]3.91-5.15 [-7.12, -2.93]7.01 [4.66, 8.95]13% [0%, 24%]26%35%-0.03+0.282026-08-08 → 2026-08-30
tmax00Znearest90d23 1 QC5.52 [3.34, 7.46]3.91-5.15 [-7.20, -2.65]7.01 [4.31, 8.83]13% [0%, 25%]26%35%-0.03+0.282026-08-08 → 2026-08-30
tmax00Znearest365d23 1 QC5.52 [3.30, 7.76]3.91-5.15 [-7.45, -2.46]7.01 [4.18, 9.14]13% [0%, 29%]26%35%-0.03+0.282026-08-08 → 2026-08-30
tmax00Znearestall23 1 QC5.52 [3.52, 7.78]3.91-5.15 [-7.45, -2.81]7.01 [4.56, 9.34]13% [0%, 27%]26%35%-0.03+0.282026-08-08 → 2026-08-30
tmax12Zbilinear30d23 1 QC5.23 [3.72, 6.87]3.05-4.90 [-6.69, -3.19]6.20 [4.50, 7.76]9% [0%, 21%]17%22%+0.02+0.432026-08-08 → 2026-08-30
tmax12Zbilinear90d23 1 QC5.23 [3.71, 7.00]3.05-4.90 [-6.90, -3.07]6.20 [4.52, 7.91]9% [0%, 22%]17%22%+0.02+0.432026-08-08 → 2026-08-30
tmax12Zbilinear365d23 1 QC5.23 [3.49, 7.11]3.05-4.90 [-7.04, -2.78]6.20 [4.22, 7.93]9% [0%, 22%]17%22%+0.02+0.432026-08-08 → 2026-08-30
tmax12Zbilinearall23 1 QC5.23 [3.66, 7.30]3.05-4.90 [-7.15, -3.14]6.20 [4.53, 8.06]9% [0%, 21%]17%22%+0.02+0.432026-08-08 → 2026-08-30
tmax12Znearest30d23 1 QC5.21 [3.71, 6.84]3.04-4.88 [-6.64, -3.21]6.18 [4.51, 7.72]9% [0%, 21%]17%22%+0.03+0.442026-08-08 → 2026-08-30
tmax12Znearest90d23 1 QC5.21 [3.71, 6.97]3.04-4.88 [-6.85, -3.09]6.18 [4.53, 7.88]9% [0%, 22%]17%22%+0.03+0.442026-08-08 → 2026-08-30
tmax12Znearest365d23 1 QC5.21 [3.50, 7.04]3.04-4.88 [-6.99, -2.81]6.18 [4.23, 7.90]9% [0%, 22%]17%22%+0.03+0.442026-08-08 → 2026-08-30
tmax12Znearestall23 1 QC5.21 [3.67, 7.27]3.04-4.88 [-7.10, -3.17]6.18 [4.55, 8.04]9% [0%, 21%]17%22%+0.03+0.442026-08-08 → 2026-08-30
tmin00Zbilinear30d23 1 QC4.36 [3.30, 5.29]3.69-2.58 [-4.78, -0.94]5.32 [4.34, 6.12]17% [7%, 27%]30%39%+0.25+0.372026-08-08 → 2026-08-30
tmin00Zbilinear90d23 1 QC4.36 [3.14, 5.43]3.69-2.58 [-5.21, -0.83]5.32 [4.18, 6.20]17% [6%, 29%]30%39%+0.25+0.372026-08-08 → 2026-08-30
tmin00Zbilinear365d23 1 QC4.36 [3.11, 5.43]3.69-2.58 [-5.21, -0.75]5.32 [4.06, 6.25]17% [3%, 29%]30%39%+0.25+0.372026-08-08 → 2026-08-30
tmin00Zbilinearall23 1 QC4.36 [3.21, 5.49]3.69-2.58 [-5.28, -0.76]5.32 [4.23, 6.31]17% [0%, 29%]30%39%+0.25+0.372026-08-08 → 2026-08-30
tmin00Znearest30d23 1 QC4.40 [3.32, 5.34]3.73-2.63 [-4.84, -1.00]5.37 [4.38, 6.17]22% [11%, 33%]30%39%+0.24+0.362026-08-08 → 2026-08-30
tmin00Znearest90d23 1 QC4.40 [3.15, 5.48]3.73-2.63 [-5.30, -0.87]5.37 [4.19, 6.28]22% [10%, 33%]30%39%+0.24+0.362026-08-08 → 2026-08-30
tmin00Znearest365d23 1 QC4.40 [3.13, 5.50]3.73-2.63 [-5.30, -0.83]5.37 [4.08, 6.33]22% [11%, 36%]30%39%+0.24+0.362026-08-08 → 2026-08-30
tmin00Znearestall23 1 QC4.40 [3.20, 5.54]3.73-2.63 [-5.36, -0.83]5.37 [4.24, 6.38]22% [10%, 35%]30%39%+0.24+0.362026-08-08 → 2026-08-30
tmin12Zbilinear30d23 1 QC4.49 [3.37, 5.73]3.72-2.66 [-4.76, -0.96]5.45 [4.42, 6.42]17% [8%, 27%]26%43%+0.23+0.362026-08-08 → 2026-08-30
tmin12Zbilinear90d23 1 QC4.49 [3.17, 5.81]3.72-2.66 [-5.20, -0.82]5.45 [4.37, 6.56]17% [8%, 30%]26%43%+0.23+0.362026-08-08 → 2026-08-30
tmin12Zbilinear365d23 1 QC4.49 [3.17, 5.88]3.72-2.66 [-5.22, -0.62]5.45 [4.31, 6.66]17% [7%, 29%]26%43%+0.23+0.362026-08-08 → 2026-08-30
tmin12Zbilinearall23 1 QC4.49 [3.18, 5.84]3.72-2.66 [-5.49, -0.65]5.45 [4.36, 6.53]17% [7%, 30%]26%43%+0.23+0.362026-08-08 → 2026-08-30
tmin12Znearest30d23 1 QC4.54 [3.38, 5.78]3.75-2.71 [-4.83, -0.99]5.49 [4.47, 6.48]13% [4%, 24%]26%43%+0.22+0.362026-08-08 → 2026-08-30
tmin12Znearest90d23 1 QC4.54 [3.18, 5.88]3.75-2.71 [-5.24, -0.87]5.49 [4.34, 6.61]13% [0%, 25%]26%43%+0.22+0.362026-08-08 → 2026-08-30
tmin12Znearest365d23 1 QC4.54 [3.15, 5.91]3.75-2.71 [-5.25, -0.68]5.49 [4.31, 6.67]13% [0%, 25%]26%43%+0.22+0.362026-08-08 → 2026-08-30
tmin12Znearestall23 1 QC4.54 [3.18, 5.90]3.75-2.71 [-5.49, -0.69]5.49 [4.34, 6.58]13% [0%, 25%]26%43%+0.22+0.362026-08-08 → 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 KPHX, lead day 7, 00Z bilinear tmax+20+100-10-202026-08-08: -7.74 °F2026-08-09: -5.09 °F2026-08-10: -4.64 °F2026-08-11: -1.11 °F2026-08-12: -9.44 °F2026-08-13: -12.41 °F2026-08-14: -2.28 °F2026-08-15: -3.32 °F2026-08-16: -1.13 °F2026-08-17: -1.17 °F2026-08-18: -3.71 °F2026-08-19: -0.63 °F2026-08-20: +4.13 °F2026-08-21: -0.52 °F2026-08-22: -9.13 °F2026-08-23: -13.41 °F2026-08-24: -15.25 °F2026-08-25: -10.35 °F2026-08-26: -7.67 °F2026-08-27: -2.27 °F2026-08-28: +0.07 °F2026-08-29: -5.6 °F2026-08-30: -5.58 °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
2026-08-30-5.58
2026-08-29-5.60
2026-08-28+0.07
2026-08-27-2.27
2026-08-26-7.67
2026-08-25-10.35
2026-08-24-15.25
2026-08-23-13.41
2026-08-22-9.13
2026-08-21-0.52
2026-08-20+4.13
2026-08-19-0.63
2026-08-18-3.71
2026-08-17-1.17
2026-08-16-1.13
2026-08-15-3.32
2026-08-14-2.28
2026-08-13-12.41
2026-08-12-9.44
2026-08-11-1.11
2026-08-10-4.64
2026-08-09-5.09
2026-08-08-7.74

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KPHX, lead day 7-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 1 day-14 to -12 °F: 2 days-12 to -10 °F: 1 day-10 to -8 °F: 2 days-8 to -6 °F: 2 days-6 to -4 °F: 4 days-4 to -2 °F: 4 days-2 to 0 °F: 5 days0 to 2 °F: 1 day2 to 4 °F: 0 days4 to 6 °F: 1 day6 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| 4.64 · P90 |e| 12 °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
-16.00-14.001
-14.00-12.002
-12.00-10.001
-10.00-8.002
-8.00-6.002
-6.00-4.004
-4.00-2.004
-2.00+0.005
+0.00+2.001
+2.00+4.000
+4.00+6.001
+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
2026-08235.51 -5.14

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 +1.20 [-1.26, 3.27] no
GraphCast (IFS init) 23 -1.44 [-3.34, 0.83] no
ECMWF IFS HRES 18 +1.80 [-1.65, 5.28] no
Persistence (baseline) 23 +0.16 [-2.73, 2.79] no

Cite this page

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

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