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

Las Vegas Harry Reid · ECMWF AIFS Single · lead day 6

KLAS · aifs_single · lead 6

Target day = initialization date + 6 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
tmax00Zbilinear30d24 2 QC7.07 [5.53, 8.46]3.86-6.53 [-8.29, -4.74]8.28 [6.42, 9.60]0% [0%, 0%]8%21%+0.10+0.502026-08-07 → 2026-08-30
tmax00Zbilinear90d24 2 QC7.07 [5.01, 8.48]3.86-6.53 [-8.23, -4.46]8.28 [5.71, 9.65]0% [0%, 0%]8%21%+0.10+0.502026-08-07 → 2026-08-30
tmax00Zbilinear365d24 2 QC7.07 [5.06, 8.61]3.86-6.53 [-8.53, -4.44]8.28 [5.69, 9.69]0% [0%, 0%]8%21%+0.10+0.502026-08-07 → 2026-08-30
tmax00Zbilinearall24 2 QC7.07 [4.96, 8.74]3.86-6.53 [-8.70, -4.33]8.28 [5.47, 9.85]0% [0%, 0%]8%21%+0.10+0.502026-08-07 → 2026-08-30
tmax00Znearest30d24 2 QC8.01 [6.53, 9.39]3.76-7.57 [-9.29, -5.81]9.06 [7.31, 10.40]0% [0%, 0%]0%12%-0.02+0.512026-08-07 → 2026-08-30
tmax00Znearest90d24 2 QC8.01 [6.08, 9.39]3.76-7.57 [-9.25, -5.55]9.06 [6.76, 10.43]0% [0%, 0%]0%12%-0.02+0.512026-08-07 → 2026-08-30
tmax00Znearest365d24 2 QC8.01 [6.18, 9.53]3.76-7.57 [-9.53, -5.55]9.06 [6.77, 10.45]0% [0%, 0%]0%12%-0.02+0.512026-08-07 → 2026-08-30
tmax00Znearestall24 2 QC8.01 [6.02, 9.71]3.76-7.57 [-9.71, -5.46]9.06 [6.45, 10.62]0% [0%, 0%]0%12%-0.02+0.512026-08-07 → 2026-08-30
tmax12Zbilinear30d24 2 QC5.73 [4.75, 6.84]2.50-5.23 [-6.74, -3.69]6.37 [5.07, 7.72]4% [0%, 12%]4%21%+0.27+0.672026-08-07 → 2026-08-30
tmax12Zbilinear90d24 2 QC5.73 [4.62, 6.96]2.50-5.23 [-6.90, -3.62]6.37 [4.90, 7.78]4% [0%, 12%]4%21%+0.27+0.672026-08-07 → 2026-08-30
tmax12Zbilinear365d24 2 QC5.73 [4.62, 7.08]2.50-5.23 [-7.08, -3.59]6.37 [4.95, 7.96]4% [0%, 14%]4%21%+0.27+0.672026-08-07 → 2026-08-30
tmax12Zbilinearall24 2 QC5.73 [4.62, 7.18]2.50-5.23 [-7.14, -3.64]6.37 [4.88, 8.20]4% [0%, 13%]4%21%+0.27+0.672026-08-07 → 2026-08-30
tmax12Znearest30d24 2 QC6.62 [5.63, 7.76]2.48-6.21 [-7.70, -4.68]7.17 [5.92, 8.51]0% [0%, 0%]4%4%+0.16+0.682026-08-07 → 2026-08-30
tmax12Znearest90d24 2 QC6.62 [5.54, 7.88]2.48-6.21 [-7.83, -4.60]7.17 [5.79, 8.58]0% [0%, 0%]4%4%+0.16+0.682026-08-07 → 2026-08-30
tmax12Znearest365d24 2 QC6.62 [5.50, 8.04]2.48-6.21 [-8.04, -4.56]7.17 [5.77, 8.79]0% [0%, 0%]4%4%+0.16+0.682026-08-07 → 2026-08-30
tmax12Znearestall24 2 QC6.62 [5.53, 8.08]2.48-6.21 [-8.07, -4.60]7.17 [5.77, 8.92]0% [0%, 0%]4%4%+0.16+0.682026-08-07 → 2026-08-30
tmin00Zbilinear30d24 2 QC5.31 [3.47, 6.80]2.28-5.10 [-6.80, -2.95]5.90 [4.33, 7.04]8% [0%, 22%]21%21%+0.28+0.692026-08-07 → 2026-08-30
tmin00Zbilinear90d24 2 QC5.31 [3.51, 6.91]2.28-5.10 [-6.91, -2.97]5.90 [4.33, 7.09]8% [0%, 22%]21%21%+0.28+0.692026-08-07 → 2026-08-30
tmin00Zbilinear365d24 2 QC5.31 [3.27, 7.02]2.28-5.10 [-7.02, -2.75]5.90 [4.08, 7.20]8% [0%, 24%]21%21%+0.28+0.692026-08-07 → 2026-08-30
tmin00Zbilinearall24 2 QC5.31 [3.34, 7.02]2.28-5.10 [-7.02, -2.79]5.90 [4.19, 7.20]8% [0%, 24%]21%21%+0.28+0.692026-08-07 → 2026-08-30
tmin00Znearest30d24 2 QC6.00 [3.94, 7.62]2.32-5.98 [-7.62, -3.86]6.68 [5.07, 7.82]12% [0%, 33%]17%21%+0.19+0.682026-08-07 → 2026-08-30
tmin00Znearest90d24 2 QC6.00 [3.95, 7.70]2.32-5.98 [-7.70, -3.89]6.68 [5.09, 7.85]12% [0%, 33%]17%21%+0.19+0.682026-08-07 → 2026-08-30
tmin00Znearest365d24 2 QC6.00 [3.74, 7.73]2.32-5.98 [-7.73, -3.67]6.68 [4.84, 7.99]12% [0%, 33%]17%21%+0.19+0.682026-08-07 → 2026-08-30
tmin00Znearestall24 2 QC6.00 [3.77, 7.73]2.32-5.98 [-7.73, -3.71]6.68 [4.88, 7.99]12% [0%, 35%]17%21%+0.19+0.682026-08-07 → 2026-08-30
tmin12Zbilinear30d24 2 QC5.45 [3.82, 6.82]2.55-5.05 [-6.82, -2.83]6.00 [4.61, 7.04]4% [0%, 11%]21%25%+0.27+0.652026-08-07 → 2026-08-30
tmin12Zbilinear90d24 2 QC5.45 [3.86, 6.92]2.55-5.05 [-6.92, -2.88]6.00 [4.63, 7.12]4% [0%, 12%]21%25%+0.27+0.652026-08-07 → 2026-08-30
tmin12Zbilinear365d24 2 QC5.45 [3.60, 6.94]2.55-5.05 [-6.94, -2.54]6.00 [4.40, 7.17]4% [0%, 12%]21%25%+0.27+0.652026-08-07 → 2026-08-30
tmin12Zbilinearall24 2 QC5.45 [3.66, 6.95]2.55-5.05 [-6.95, -2.70]6.00 [4.50, 7.18]4% [0%, 13%]21%25%+0.27+0.652026-08-07 → 2026-08-30
tmin12Znearest30d24 2 QC6.08 [4.19, 7.57]2.59-5.87 [-7.57, -3.65]6.72 [5.25, 7.78]8% [0%, 21%]17%21%+0.18+0.652026-08-07 → 2026-08-30
tmin12Znearest90d24 2 QC6.08 [4.24, 7.68]2.59-5.87 [-7.68, -3.70]6.72 [5.29, 7.87]8% [0%, 21%]17%21%+0.18+0.652026-08-07 → 2026-08-30
tmin12Znearest365d24 2 QC6.08 [3.99, 7.71]2.59-5.87 [-7.71, -3.42]6.72 [5.06, 7.88]8% [0%, 22%]17%21%+0.18+0.652026-08-07 → 2026-08-30
tmin12Znearestall24 2 QC6.08 [4.07, 7.70]2.59-5.87 [-7.70, -3.52]6.72 [5.15, 7.89]8% [0%, 22%]17%21%+0.18+0.652026-08-07 → 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 6, 00Z bilinear tmax+20+100-10-202026-08-07: -7.39 °F2026-08-08: -5.56 °F2026-08-09: -4.73 °F2026-08-10: -4.28 °F2026-08-11: -6.12 °F2026-08-12: -14.06 °F2026-08-13: -2.04 °F2026-08-14: -15.69 °F2026-08-15: +6.41 °F2026-08-16: -1.51 °F2026-08-17: -6.11 °F2026-08-18: -8.11 °F2026-08-19: -5.1 °F2026-08-20: -2.4 °F2026-08-21: -8.52 °F2026-08-22: -11.16 °F2026-08-23: -8.52 °F2026-08-24: -11.88 °F2026-08-25: -6.81 °F2026-08-26: -17.37 °F2026-08-27: -8.67 °F2026-08-28: -1.46 °F2026-08-29: -3.62 °F2026-08-30: -2.13 °F2026-08-072026-08-30°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 (24 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-2.13
2026-08-29-3.62
2026-08-28-1.46
2026-08-27-8.67
2026-08-26-17.37
2026-08-25-6.81
2026-08-24-11.88
2026-08-23-8.52
2026-08-22-11.16
2026-08-21-8.52
2026-08-20-2.40
2026-08-19-5.10
2026-08-18-8.11
2026-08-17-6.11
2026-08-16-1.51
2026-08-15+6.41
2026-08-14-15.69
2026-08-13-2.04
2026-08-12-14.06
2026-08-11-6.12
2026-08-10-4.28
2026-08-09-4.73
2026-08-08-5.56
2026-08-07-7.39

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KLAS, lead day 6-20 to -18 °F: 0 days-18 to -16 °F: 1 day-16 to -14 °F: 2 days-14 to -12 °F: 0 days-12 to -10 °F: 2 days-10 to -8 °F: 4 days-8 to -6 °F: 4 days-6 to -4 °F: 4 days-4 to -2 °F: 4 days-2 to 0 °F: 2 days0 to 2 °F: 0 days2 to 4 °F: 0 days4 to 6 °F: 0 days6 to 8 °F: 1 day8 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| 6.27 · P90 |e| 13.4 °F-200+20 °Fn = 24 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
-18.00-16.001
-16.00-14.002
-14.00-12.000
-12.00-10.002
-10.00-8.004
-8.00-6.004
-6.00-4.004
-4.00-2.004
-2.00+0.002
+0.00+2.000
+2.00+4.000
+4.00+6.000
+6.00+8.001
+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
2026-08247.07 -6.53

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-07 → 2026-08-30 24
ECMWF AIFS Single2026-08-07 → 2026-08-30 24
ECMWF AIFS Single2026-08-07 → 2026-08-30 24
ECMWF AIFS Single2026-08-07 → 2026-08-30 24

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 24 +1.84 [0.11, 3.29] yes
GraphCast (IFS init) 24 -1.33 [-3.54, 0.30] no
ECMWF IFS HRES 19 +3.18 [1.46, 5.39] yes
Persistence (baseline) 24 -0.81 [-4.77, 4.01] no

Cite this page

ShortCastCheck, KLAS aifs_single lead 6, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KLAS/model/aifs_single/lead/6/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KLAS (Las Vegas Harry Reid), model aifs_single, lead day 6. 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/6/

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