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

Las Vegas Harry Reid · ECMWF AIFS Single · lead day 0

KLAS · aifs_single · 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, 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, 2 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
tmax00Zbilinear30d30 2 QC5.08 [4.12, 6.07]1.77-4.82 [-5.58, -4.00]5.61 [4.35, 6.87]0% [0%, 0%]3%13%——2026-08-01 → 2026-08-30
tmax00Zbilinear90d30 2 QC5.08 [4.03, 6.05]1.77-4.82 [-5.61, -3.93]5.61 [4.22, 6.81]0% [0%, 0%]3%13%——2026-08-01 → 2026-08-30
tmax00Zbilinear365d30 2 QC5.08 [3.98, 6.16]1.77-4.82 [-5.57, -3.92]5.61 [4.16, 7.04]0% [0%, 0%]3%13%——2026-08-01 → 2026-08-30
tmax00Zbilinearall30 2 QC5.08 [3.90, 6.11]1.77-4.82 [-5.69, -3.87]5.61 [4.10, 6.91]0% [0%, 0%]3%13%——2026-08-01 → 2026-08-30
tmax00Znearest30d30 2 QC6.10 [5.29, 6.88]1.78-5.89 [-6.56, -5.16]6.52 [5.48, 7.56]0% [0%, 0%]0%0%——2026-08-01 → 2026-08-30
tmax00Znearest90d30 2 QC6.10 [5.20, 6.86]1.78-5.89 [-6.61, -5.05]6.52 [5.32, 7.49]0% [0%, 0%]0%0%——2026-08-01 → 2026-08-30
tmax00Znearest365d30 2 QC6.10 [5.16, 6.92]1.78-5.89 [-6.62, -5.03]6.52 [5.33, 7.66]0% [0%, 0%]0%0%——2026-08-01 → 2026-08-30
tmax00Znearestall30 2 QC6.10 [5.14, 6.96]1.78-5.89 [-6.69, -5.07]6.52 [5.29, 7.59]0% [0%, 0%]0%0%——2026-08-01 → 2026-08-30
tmin00Zbilinear30d30 2 QC4.99 [3.47, 6.15]1.77-4.92 [-6.15, -3.26]5.44 [4.27, 6.29]10% [0%, 27%]17%17%——2026-08-01 → 2026-08-30
tmin00Zbilinear90d30 2 QC4.99 [3.56, 6.31]1.77-4.92 [-6.31, -3.36]5.44 [4.32, 6.44]10% [0%, 28%]17%17%——2026-08-01 → 2026-08-30
tmin00Zbilinear365d30 2 QC4.99 [3.24, 6.32]1.77-4.92 [-6.32, -3.03]5.44 [4.02, 6.44]10% [0%, 30%]17%17%——2026-08-01 → 2026-08-30
tmin00Zbilinearall30 2 QC4.99 [3.51, 6.34]1.77-4.92 [-6.34, -3.28]5.44 [4.21, 6.47]10% [0%, 29%]17%17%——2026-08-01 → 2026-08-30
tmin00Znearest30d30 2 QC5.85 [4.07, 7.25]1.86-5.85 [-7.25, -4.07]6.37 [4.95, 7.43]10% [0%, 27%]17%17%——2026-08-01 → 2026-08-30
tmin00Znearest90d30 2 QC5.85 [4.15, 7.49]1.86-5.85 [-7.49, -4.15]6.37 [5.05, 7.64]10% [0%, 28%]17%17%——2026-08-01 → 2026-08-30
tmin00Znearest365d30 2 QC5.85 [3.76, 7.47]1.86-5.85 [-7.47, -3.76]6.37 [4.69, 7.60]10% [0%, 30%]17%17%——2026-08-01 → 2026-08-30
tmin00Znearestall30 2 QC5.85 [4.04, 7.55]1.86-5.85 [-7.55, -4.04]6.37 [4.94, 7.70]10% [0%, 29%]17%17%——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 AIFS Single at KLAS, lead day 0, 00Z bilinear tmax+20+100-10-202026-08-01: -3.61 °F2026-08-02: -2.6 °F2026-08-03: -3.49 °F2026-08-04: -3.4 °F2026-08-05: -5.27 °F2026-08-06: -1.87 °F2026-08-07: -5.93 °F2026-08-08: -5.41 °F2026-08-09: -4.93 °F2026-08-10: -2.88 °F2026-08-11: -6.03 °F2026-08-12: -10.45 °F2026-08-13: -4.83 °F2026-08-14: -14.06 °F2026-08-15: +3.9 °F2026-08-16: -4.38 °F2026-08-17: -5.1 °F2026-08-18: -4.54 °F2026-08-19: -3.45 °F2026-08-20: -5.4 °F2026-08-21: -4.54 °F2026-08-22: -4.09 °F2026-08-23: -4.85 °F2026-08-24: -6.18 °F2026-08-25: -5.46 °F2026-08-26: -3.88 °F2026-08-27: -7.73 °F2026-08-28: -6.95 °F2026-08-29: -5.15 °F2026-08-30: -2.17 °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
2026-08-30-2.17
2026-08-29-5.15
2026-08-28-6.95
2026-08-27-7.73
2026-08-26-3.88
2026-08-25-5.46
2026-08-24-6.18
2026-08-23-4.85
2026-08-22-4.09
2026-08-21-4.54
2026-08-20-5.40
2026-08-19-3.45
2026-08-18-4.54
2026-08-17-5.10
2026-08-16-4.38
2026-08-15+3.90
2026-08-14-14.06
2026-08-13-4.83
2026-08-12-10.45
2026-08-11-6.03
2026-08-10-2.88
2026-08-09-4.93
2026-08-08-5.41
2026-08-07-5.93
2026-08-06-1.87
2026-08-05-5.27
2026-08-04-3.40
2026-08-03-3.49
2026-08-02-2.60
2026-08-01-3.61

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KLAS, lead day 0-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 1 day-14 to -12 °F: 0 days-12 to -10 °F: 1 day-10 to -8 °F: 0 days-8 to -6 °F: 4 days-6 to -4 °F: 14 days-4 to -2 °F: 8 days-2 to 0 °F: 1 day0 to 2 °F: 0 days2 to 4 °F: 1 day4 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| 4.84 · P90 |e| 7.03 °F-200+20 °Fn = 30 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
-14.00-12.000
-12.00-10.001
-10.00-8.000
-8.00-6.004
-6.00-4.0014
-4.00-2.008
-2.00+0.001
+0.00+2.000
+2.00+4.001
+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
2026-08305.08 -4.82

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-01 → 2026-08-30 30
ECMWF AIFS Single2026-08-01 → 2026-08-30 30

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
Aurora (GFS init) 2 -1.72 [-1.87, -1.57] yes
Aurora (IFS init) 3 +0.79 [-0.38, 2.13] no
FourCastNet v2 (GFS init) 2 -1.60 [-1.86, -1.34] yes
FourCastNet v2 (IFS init) 3 -1.17 [-1.84, -0.83] yes
NCEP GFS 30 +0.01 [-1.03, 1.26] no
GraphCast (GFS init) 2 -4.28 [-4.71, -3.86] yes
GraphCast (IFS init) 28 -0.14 [-0.69, 0.26] no
ECMWF IFS HRES 25 +1.38 [0.75, 2.09] yes
Pangu-Weather (GFS init) 2 -1.50 [-1.57, -1.42] yes
Pangu-Weather (IFS init) 3 -0.56 [-1.19, 0.71] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KLAS (Las Vegas Harry Reid), model aifs_single, 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/KLAS/model/aifs_single/lead/0/

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

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