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

Las Vegas Harry Reid · ECMWF AIFS Single · lead day 7

KLAS · 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, 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
tmax00Zbilinear30d23 2 QC7.03 [4.89, 9.01]4.32-6.78 [-9.00, -4.41]8.51 [6.09, 10.35]4% [0%, 17%]17%30%+0.17+0.482026-08-08 → 2026-08-30
tmax00Zbilinear90d23 2 QC7.03 [4.37, 9.19]4.32-6.78 [-9.16, -4.05]8.51 [5.46, 10.51]4% [0%, 20%]17%30%+0.17+0.482026-08-08 → 2026-08-30
tmax00Zbilinear365d23 2 QC7.03 [4.30, 9.26]4.32-6.78 [-9.26, -3.96]8.51 [5.26, 10.60]4% [0%, 20%]17%30%+0.17+0.482026-08-08 → 2026-08-30
tmax00Zbilinearall23 2 QC7.03 [4.49, 9.26]4.32-6.78 [-9.26, -4.10]8.51 [5.58, 10.64]4% [0%, 25%]17%30%+0.17+0.482026-08-08 → 2026-08-30
tmax00Znearest30d23 2 QC8.00 [5.86, 9.98]4.18-7.83 [-9.97, -5.57]9.30 [6.94, 11.17]0% [0%, 0%]4%22%+0.05+0.502026-08-08 → 2026-08-30
tmax00Znearest90d23 2 QC8.00 [5.42, 10.16]4.18-7.83 [-10.16, -5.21]9.30 [6.36, 11.33]0% [0%, 0%]4%22%+0.05+0.502026-08-08 → 2026-08-30
tmax00Znearest365d23 2 QC8.00 [5.42, 10.30]4.18-7.83 [-10.30, -5.11]9.30 [6.15, 11.38]0% [0%, 0%]4%22%+0.05+0.502026-08-08 → 2026-08-30
tmax00Znearestall23 2 QC8.00 [5.57, 10.28]4.18-7.83 [-10.28, -5.27]9.30 [6.44, 11.47]0% [0%, 0%]4%22%+0.05+0.502026-08-08 → 2026-08-30
tmax12Zbilinear30d23 2 QC6.52 [4.90, 8.09]3.86-5.77 [-7.87, -3.71]7.58 [5.67, 9.07]4% [0%, 15%]17%26%+0.23+0.542026-08-08 → 2026-08-30
tmax12Zbilinear90d23 2 QC6.52 [4.30, 8.22]3.86-5.77 [-8.09, -3.41]7.58 [5.21, 9.18]4% [0%, 18%]17%26%+0.23+0.542026-08-08 → 2026-08-30
tmax12Zbilinear365d23 2 QC6.52 [4.55, 8.32]3.86-5.77 [-8.27, -3.41]7.58 [5.21, 9.36]4% [0%, 18%]17%26%+0.23+0.542026-08-08 → 2026-08-30
tmax12Zbilinearall23 2 QC6.52 [4.32, 8.31]3.86-5.77 [-8.25, -3.42]7.58 [5.01, 9.40]4% [0%, 20%]17%26%+0.23+0.542026-08-08 → 2026-08-30
tmax12Znearest30d23 2 QC7.44 [5.84, 9.05]3.88-6.82 [-8.88, -4.79]8.38 [6.51, 9.88]4% [0%, 15%]4%22%+0.12+0.532026-08-08 → 2026-08-30
tmax12Znearest90d23 2 QC7.44 [5.32, 9.19]3.88-6.82 [-9.11, -4.48]8.38 [6.13, 10.05]4% [0%, 18%]4%22%+0.12+0.532026-08-08 → 2026-08-30
tmax12Znearest365d23 2 QC7.44 [5.52, 9.29]3.88-6.82 [-9.29, -4.42]8.38 [6.14, 10.24]4% [0%, 18%]4%22%+0.12+0.532026-08-08 → 2026-08-30
tmax12Znearestall23 2 QC7.44 [5.27, 9.32]3.88-6.82 [-9.28, -4.46]8.38 [5.91, 10.21]4% [0%, 20%]4%22%+0.12+0.532026-08-08 → 2026-08-30
tmin00Zbilinear30d23 2 QC6.17 [4.03, 8.03]2.70-6.13 [-8.03, -3.95]7.08 [4.71, 8.77]9% [0%, 22%]9%22%+0.20+0.652026-08-08 → 2026-08-30
tmin00Zbilinear90d23 2 QC6.17 [3.98, 8.30]2.70-6.13 [-8.30, -3.90]7.08 [4.61, 8.98]9% [0%, 22%]9%22%+0.20+0.652026-08-08 → 2026-08-30
tmin00Zbilinear365d23 2 QC6.17 [3.79, 8.26]2.70-6.13 [-8.26, -3.70]7.08 [4.38, 9.01]9% [0%, 22%]9%22%+0.20+0.652026-08-08 → 2026-08-30
tmin00Zbilinearall23 2 QC6.17 [3.81, 8.41]2.70-6.13 [-8.41, -3.72]7.08 [4.41, 9.03]9% [0%, 24%]9%22%+0.20+0.652026-08-08 → 2026-08-30
tmin00Znearest30d23 2 QC7.02 [4.85, 8.90]2.69-7.02 [-8.90, -4.85]7.88 [5.54, 9.53]4% [0%, 12%]9%9%+0.09+0.652026-08-08 → 2026-08-30
tmin00Znearest90d23 2 QC7.02 [4.80, 9.12]2.69-7.02 [-9.12, -4.80]7.88 [5.43, 9.73]4% [0%, 12%]9%9%+0.09+0.652026-08-08 → 2026-08-30
tmin00Znearest365d23 2 QC7.02 [4.58, 9.08]2.69-7.02 [-9.08, -4.58]7.88 [5.16, 9.80]4% [0%, 13%]9%9%+0.09+0.652026-08-08 → 2026-08-30
tmin00Znearestall23 2 QC7.02 [4.60, 9.22]2.69-7.02 [-9.22, -4.60]7.88 [5.22, 9.81]4% [0%, 14%]9%9%+0.09+0.652026-08-08 → 2026-08-30
tmin12Zbilinear30d23 2 QC5.46 [3.80, 6.83]2.62-5.05 [-6.83, -2.81]6.06 [4.56, 7.16]4% [0%, 12%]17%17%+0.29+0.662026-08-08 → 2026-08-30
tmin12Zbilinear90d23 2 QC5.46 [3.72, 6.96]2.62-5.05 [-6.96, -2.82]6.06 [4.38, 7.27]4% [0%, 13%]17%17%+0.29+0.662026-08-08 → 2026-08-30
tmin12Zbilinear365d23 2 QC5.46 [3.54, 7.01]2.62-5.05 [-7.01, -2.60]6.06 [4.27, 7.32]4% [0%, 13%]17%17%+0.29+0.662026-08-08 → 2026-08-30
tmin12Zbilinearall23 2 QC5.46 [3.57, 7.03]2.62-5.05 [-7.03, -2.58]6.06 [4.23, 7.36]4% [0%, 14%]17%17%+0.29+0.662026-08-08 → 2026-08-30
tmin12Znearest30d23 2 QC6.10 [4.21, 7.60]2.64-5.90 [-7.60, -3.71]6.79 [5.25, 7.87]13% [0%, 32%]17%17%+0.21+0.662026-08-08 → 2026-08-30
tmin12Znearest90d23 2 QC6.10 [4.19, 7.68]2.64-5.90 [-7.68, -3.72]6.79 [5.15, 7.99]13% [0%, 31%]17%17%+0.21+0.662026-08-08 → 2026-08-30
tmin12Znearest365d23 2 QC6.10 [3.94, 7.70]2.64-5.90 [-7.70, -3.50]6.79 [4.93, 8.01]13% [0%, 33%]17%17%+0.21+0.662026-08-08 → 2026-08-30
tmin12Znearestall23 2 QC6.10 [3.98, 7.70]2.64-5.90 [-7.70, -3.47]6.79 [4.95, 8.03]13% [0%, 33%]17%17%+0.21+0.662026-08-08 → 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 KLAS, lead day 7, 00Z bilinear tmax+20+100-10-202026-08-08: -13.2 °F2026-08-09: -2.22 °F2026-08-10: -7.27 °F2026-08-11: -2.82 °F2026-08-12: -13.95 °F2026-08-13: -10.25 °F2026-08-14: -8.61 °F2026-08-15: +2.96 °F2026-08-16: -1.33 °F2026-08-17: -4.27 °F2026-08-18: -5.82 °F2026-08-19: -6.24 °F2026-08-20: -4 °F2026-08-21: -1.42 °F2026-08-22: -6.73 °F2026-08-23: -13.24 °F2026-08-24: -18.2 °F2026-08-25: -9.43 °F2026-08-26: -11.3 °F2026-08-27: -11.95 °F2026-08-28: -4.33 °F2026-08-29: -1.45 °F2026-08-30: -0.8 °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
2026-08-30-0.80
2026-08-29-1.45
2026-08-28-4.33
2026-08-27-11.95
2026-08-26-11.30
2026-08-25-9.43
2026-08-24-18.20
2026-08-23-13.24
2026-08-22-6.73
2026-08-21-1.42
2026-08-20-4.00
2026-08-19-6.24
2026-08-18-5.82
2026-08-17-4.27
2026-08-16-1.33
2026-08-15+2.96
2026-08-14-8.61
2026-08-13-10.25
2026-08-12-13.95
2026-08-11-2.82
2026-08-10-7.27
2026-08-09-2.22
2026-08-08-13.20

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KLAS, lead day 7-20 to -18 °F: 1 day-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 3 days-12 to -10 °F: 3 days-10 to -8 °F: 2 days-8 to -6 °F: 3 days-6 to -4 °F: 4 days-4 to -2 °F: 2 days-2 to 0 °F: 4 days0 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| 6.24 · P90 |e| 13.23 °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
-20.00-18.001
-18.00-16.000
-16.00-14.000
-14.00-12.003
-12.00-10.003
-10.00-8.002
-8.00-6.003
-6.00-4.004
-4.00-2.002
-2.00+0.004
+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
2026-08237.03 -6.78

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 +0.28 [-2.12, 2.98] no
GraphCast (IFS init) 23 -1.88 [-4.27, -0.02] yes
ECMWF IFS HRES 18 +2.28 [-0.93, 5.79] no
Persistence (baseline) 23 -1.40 [-6.28, 4.70] no

Cite this page

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

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