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

Las Vegas Harry Reid · ECMWF AIFS Single · lead day 8

KLAS · aifs_single · lead 8

Target day = initialization date + 8 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
tmax00Zbilinear30d22 2 QC8.25 [5.40, 11.25]5.32-8.08 [-11.08, -5.01]10.42 [6.54, 13.57]5% [0%, 12%]9%18%+0.08+0.402026-08-09 → 2026-08-30
tmax00Zbilinear90d22 2 QC8.25 [4.74, 11.52]5.32-8.08 [-11.36, -4.31]10.42 [5.64, 13.78]5% [0%, 13%]9%18%+0.08+0.402026-08-09 → 2026-08-30
tmax00Zbilinear365d22 2 QC8.25 [4.85, 11.91]5.32-8.08 [-11.68, -4.40]10.42 [5.64, 14.40]5% [0%, 14%]9%18%+0.08+0.402026-08-09 → 2026-08-30
tmax00Zbilinearall22 2 QC8.25 [4.83, 11.74]5.32-8.08 [-11.51, -4.15]10.42 [5.68, 14.05]5% [0%, 14%]9%18%+0.08+0.402026-08-09 → 2026-08-30
tmax00Znearest30d22 2 QC9.19 [6.29, 12.20]5.25-9.15 [-12.16, -6.17]11.22 [7.40, 14.43]5% [0%, 19%]9%9%-0.03+0.402026-08-09 → 2026-08-30
tmax00Znearest90d22 2 QC9.19 [5.63, 12.47]5.25-9.15 [-12.45, -5.49]11.22 [6.67, 14.67]5% [0%, 22%]9%9%-0.03+0.402026-08-09 → 2026-08-30
tmax00Znearest365d22 2 QC9.19 [5.72, 12.83]5.25-9.15 [-12.82, -5.57]11.22 [6.63, 15.25]5% [0%, 22%]9%9%-0.03+0.402026-08-09 → 2026-08-30
tmax00Znearestall22 2 QC9.19 [5.53, 12.69]5.25-9.15 [-12.63, -5.34]11.22 [6.71, 14.94]5% [0%, 26%]9%9%-0.03+0.402026-08-09 → 2026-08-30
tmax12Zbilinear30d22 2 QC6.98 [4.63, 9.56]4.74-6.46 [-9.14, -3.41]8.98 [5.66, 11.86]5% [0%, 12%]18%23%+0.22+0.462026-08-09 → 2026-08-30
tmax12Zbilinear90d22 2 QC6.98 [3.79, 9.71]4.74-6.46 [-9.34, -2.81]8.98 [4.49, 12.02]5% [0%, 12%]18%23%+0.22+0.462026-08-09 → 2026-08-30
tmax12Zbilinear365d22 2 QC6.98 [3.94, 10.10]4.74-6.46 [-9.69, -2.75]8.98 [4.45, 12.40]5% [0%, 14%]18%23%+0.22+0.462026-08-09 → 2026-08-30
tmax12Zbilinearall22 2 QC6.98 [3.58, 10.07]4.74-6.46 [-9.76, -2.71]8.98 [3.87, 12.35]5% [0%, 14%]18%23%+0.22+0.462026-08-09 → 2026-08-30
tmax12Znearest30d22 2 QC7.84 [5.35, 10.43]4.65-7.53 [-10.11, -4.58]9.69 [6.41, 12.51]5% [0%, 12%]5%23%+0.12+0.472026-08-09 → 2026-08-30
tmax12Znearest90d22 2 QC7.84 [4.73, 10.66]4.65-7.53 [-10.34, -3.98]9.69 [5.39, 12.69]5% [0%, 13%]5%23%+0.12+0.472026-08-09 → 2026-08-30
tmax12Znearest365d22 2 QC7.84 [4.73, 10.97]4.65-7.53 [-10.67, -3.84]9.69 [5.27, 13.07]5% [0%, 14%]5%23%+0.12+0.472026-08-09 → 2026-08-30
tmax12Znearestall22 2 QC7.84 [4.65, 10.97]4.65-7.53 [-10.75, -3.79]9.69 [4.65, 13.01]5% [0%, 14%]5%23%+0.12+0.472026-08-09 → 2026-08-30
tmin00Zbilinear30d22 2 QC6.71 [4.37, 9.05]3.14-6.37 [-9.05, -3.54]7.49 [4.91, 9.49]0% [0%, 0%]5%14%+0.18+0.622026-08-09 → 2026-08-30
tmin00Zbilinear90d22 2 QC6.71 [4.22, 9.34]3.14-6.37 [-9.34, -3.31]7.49 [4.74, 9.75]0% [0%, 0%]5%14%+0.18+0.622026-08-09 → 2026-08-30
tmin00Zbilinear365d22 2 QC6.71 [4.02, 9.42]3.14-6.37 [-9.42, -3.20]7.49 [4.57, 9.82]0% [0%, 0%]5%14%+0.18+0.622026-08-09 → 2026-08-30
tmin00Zbilinearall22 2 QC6.71 [3.99, 9.28]3.14-6.37 [-9.28, -3.21]7.49 [4.54, 9.65]0% [0%, 0%]5%14%+0.18+0.622026-08-09 → 2026-08-30
tmin00Znearest30d22 2 QC7.50 [4.92, 9.92]3.17-7.30 [-9.92, -4.43]8.30 [5.64, 10.31]5% [0%, 13%]5%14%+0.08+0.612026-08-09 → 2026-08-30
tmin00Znearest90d22 2 QC7.50 [4.77, 10.23]3.17-7.30 [-10.23, -4.23]8.30 [5.46, 10.57]5% [0%, 14%]5%14%+0.08+0.612026-08-09 → 2026-08-30
tmin00Znearest365d22 2 QC7.50 [4.53, 10.29]3.17-7.30 [-10.29, -4.08]8.30 [5.27, 10.62]5% [0%, 14%]5%14%+0.08+0.612026-08-09 → 2026-08-30
tmin00Znearestall22 2 QC7.50 [4.55, 10.16]3.17-7.30 [-10.16, -4.10]8.30 [5.25, 10.48]5% [0%, 14%]5%14%+0.08+0.612026-08-09 → 2026-08-30
tmin12Zbilinear30d22 2 QC5.43 [3.41, 7.19]2.93-5.18 [-7.19, -2.80]6.41 [4.22, 7.96]14% [0%, 35%]18%27%+0.34+0.642026-08-09 → 2026-08-30
tmin12Zbilinear90d22 2 QC5.43 [3.21, 7.32]2.93-5.18 [-7.32, -2.63]6.41 [3.85, 8.09]14% [0%, 36%]18%27%+0.34+0.642026-08-09 → 2026-08-30
tmin12Zbilinear365d22 2 QC5.43 [3.10, 7.46]2.93-5.18 [-7.46, -2.45]6.41 [3.79, 8.18]14% [0%, 36%]18%27%+0.34+0.642026-08-09 → 2026-08-30
tmin12Zbilinearall22 2 QC5.43 [3.12, 7.46]2.93-5.18 [-7.46, -2.49]6.41 [3.81, 8.23]14% [0%, 38%]18%27%+0.34+0.642026-08-09 → 2026-08-30
tmin12Znearest30d22 2 QC6.18 [3.95, 8.07]2.93-6.09 [-8.07, -3.73]7.18 [4.97, 8.73]14% [0%, 35%]18%18%+0.24+0.642026-08-09 → 2026-08-30
tmin12Znearest90d22 2 QC6.18 [3.79, 8.15]2.93-6.09 [-8.15, -3.55]7.18 [4.62, 8.77]14% [0%, 35%]18%18%+0.24+0.642026-08-09 → 2026-08-30
tmin12Znearest365d22 2 QC6.18 [3.66, 8.24]2.93-6.09 [-8.24, -3.40]7.18 [4.55, 8.86]14% [0%, 36%]18%18%+0.24+0.642026-08-09 → 2026-08-30
tmin12Znearestall22 2 QC6.18 [3.70, 8.28]2.93-6.09 [-8.28, -3.45]7.18 [4.60, 8.96]14% [0%, 38%]18%18%+0.24+0.642026-08-09 → 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 8, 00Z bilinear tmax+25+12.50-12.5-252026-08-09: -9.26 °F2026-08-10: -2.16 °F2026-08-11: -6.97 °F2026-08-12: -9.87 °F2026-08-13: -8.02 °F2026-08-14: -16.98 °F2026-08-15: -0.06 °F2026-08-16: -3.52 °F2026-08-17: -11.62 °F2026-08-18: -4.08 °F2026-08-19: -5.05 °F2026-08-20: -3.78 °F2026-08-21: -2.08 °F2026-08-22: -3.84 °F2026-08-23: -10.79 °F2026-08-24: -18.32 °F2026-08-25: -19.64 °F2026-08-26: -24.09 °F2026-08-27: -10.76 °F2026-08-28: -4.9 °F2026-08-29: -3.92 °F2026-08-30: +1.86 °F2026-08-092026-08-30°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 (22 days, newest first) · download CSV
Climatological dayError °F
2026-08-30+1.86
2026-08-29-3.92
2026-08-28-4.90
2026-08-27-10.76
2026-08-26-24.09
2026-08-25-19.64
2026-08-24-18.32
2026-08-23-10.79
2026-08-22-3.84
2026-08-21-2.08
2026-08-20-3.78
2026-08-19-5.05
2026-08-18-4.08
2026-08-17-11.62
2026-08-16-3.52
2026-08-15-0.06
2026-08-14-16.98
2026-08-13-8.02
2026-08-12-9.87
2026-08-11-6.97
2026-08-10-2.16
2026-08-09-9.26

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KLAS, lead day 8-25 to -22.5 °F: 1 day-22.5 to -20 °F: 0 days-20 to -17.5 °F: 2 days-17.5 to -15 °F: 1 day-15 to -12.5 °F: 0 days-12.5 to -10 °F: 3 days-10 to -7.5 °F: 3 days-7.5 to -5 °F: 2 days-5 to -2.5 °F: 6 days-2.5 to 0 °F: 3 days0 to 2.5 °F: 1 day2.5 to 5 °F: 0 days5 to 7.5 °F: 0 days7.5 to 10 °F: 0 days10 to 12.5 °F: 0 days12.5 to 15 °F: 0 days15 to 17.5 °F: 0 days17.5 to 20 °F: 0 days20 to 22.5 °F: 0 days22.5 to 25 °F: 0 daysdashed: P50 |e| 6.01 · P90 |e| 18.18 °F-250+25 °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
-25.00-22.501
-22.50-20.000
-20.00-17.502
-17.50-15.001
-15.00-12.500
-12.50-10.003
-10.00-7.503
-7.50-5.002
-5.00-2.506
-2.50+0.003
+0.00+2.501
+2.50+5.000
+5.00+7.500
+7.50+10.000
+10.00+12.500
+12.50+15.000
+15.00+17.500
+17.50+20.000
+20.00+22.500
+22.50+25.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08228.25 -8.08

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22
ECMWF AIFS Single2026-08-09 → 2026-08-30 22

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 22 +2.26 [-1.43, 5.42] no
GraphCast (IFS init) 22 -2.21 [-6.46, 0.66] no
ECMWF IFS HRES 17 +1.79 [-4.14, 8.01] no
Persistence (baseline) 22 -0.70 [-5.24, 5.91] no

Cite this page

ShortCastCheck, KLAS aifs_single lead 8, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KLAS/model/aifs_single/lead/8/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KLAS (Las Vegas Harry Reid), model aifs_single, lead day 8. 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/8/

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