Raw model output on the native 0.25° grid — no MOS, no bias correction, no post-processing. Scores understate operational forecast quality. Read the fairness statement →

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

Las Vegas Harry Reid · NCEP GFS · lead day 5

KLAS · gfs · lead 5

Target day = initialization date + 5 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, gfs-0p25, 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
tmax00Zbilinear30d25 2 QC4.72 [3.25, 5.74]3.65-3.16 [-5.53, -0.46]5.49 [4.32, 6.25]12% [0%, 29%]20%32%+0.33+0.472026-08-06 → 2026-08-30
tmax00Zbilinear90d25 2 QC4.72 [2.94, 5.81]3.65-3.16 [-5.64, -0.09]5.49 [4.01, 6.29]12% [0%, 31%]20%32%+0.33+0.472026-08-06 → 2026-08-30
tmax00Zbilinear365d25 2 QC4.72 [3.01, 5.93]3.65-3.16 [-5.91, -0.00]5.49 [3.98, 6.31]12% [0%, 33%]20%32%+0.33+0.472026-08-06 → 2026-08-30
tmax00Zbilinearall25 2 QC4.72 [2.83, 6.03]3.65-3.16 [-6.02, 0.07]5.49 [3.92, 6.45]12% [0%, 31%]20%32%+0.33+0.472026-08-06 → 2026-08-30
tmax00Znearest30d25 2 QC5.83 [4.07, 7.33]3.67-4.76 [-7.28, -1.96]6.59 [4.98, 7.80]4% [0%, 11%]12%20%+0.17+0.472026-08-06 → 2026-08-30
tmax00Znearest90d25 2 QC5.83 [3.79, 7.47]3.67-4.76 [-7.36, -1.50]6.59 [4.74, 7.89]4% [0%, 11%]12%20%+0.17+0.472026-08-06 → 2026-08-30
tmax00Znearest365d25 2 QC5.83 [3.87, 7.65]3.67-4.76 [-7.65, -1.35]6.59 [4.72, 7.97]4% [0%, 12%]12%20%+0.17+0.472026-08-06 → 2026-08-30
tmax00Znearestall25 2 QC5.83 [3.71, 7.76]3.67-4.76 [-7.74, -1.32]6.59 [4.51, 8.14]4% [0%, 12%]12%20%+0.17+0.472026-08-06 → 2026-08-30
tmax12Zbilinear30d25 2 QC4.51 [2.65, 5.88]3.76-2.53 [-5.62, 0.82]5.32 [3.42, 6.46]16% [0%, 35%]24%24%+0.36+0.452026-08-06 → 2026-08-30
tmax12Zbilinear90d25 2 QC4.51 [2.14, 5.98]3.76-2.53 [-5.66, 1.17]5.32 [2.70, 6.50]16% [0%, 40%]24%24%+0.36+0.452026-08-06 → 2026-08-30
tmax12Zbilinear365d25 2 QC4.51 [2.24, 6.06]3.76-2.53 [-5.99, 1.30]5.32 [2.75, 6.56]16% [0%, 40%]24%24%+0.36+0.452026-08-06 → 2026-08-30
tmax12Zbilinearall25 2 QC4.51 [2.07, 6.17]3.76-2.53 [-6.17, 1.22]5.32 [2.59, 6.64]16% [0%, 39%]24%24%+0.36+0.452026-08-06 → 2026-08-30
tmax12Znearest30d25 2 QC5.29 [3.19, 7.11]3.56-4.13 [-6.98, -0.94]6.01 [3.95, 7.41]4% [0%, 12%]24%28%+0.24+0.482026-08-06 → 2026-08-30
tmax12Znearest90d25 2 QC5.29 [2.47, 7.18]3.56-4.13 [-7.06, -0.62]6.01 [2.91, 7.48]4% [0%, 13%]24%28%+0.24+0.482026-08-06 → 2026-08-30
tmax12Znearest365d25 2 QC5.29 [2.44, 7.33]3.56-4.13 [-7.33, -0.56]6.01 [2.89, 7.60]4% [0%, 13%]24%28%+0.24+0.482026-08-06 → 2026-08-30
tmax12Znearestall25 2 QC5.29 [2.55, 7.36]3.56-4.13 [-7.34, -0.57]6.01 [3.09, 7.63]4% [0%, 14%]24%28%+0.24+0.482026-08-06 → 2026-08-30
tmin00Zbilinear30d25 2 QC3.37 [1.82, 5.29]3.38+0.44 [-2.51, 3.53]4.64 [2.39, 6.63]28% [5%, 50%]48%60%+0.49+0.492026-08-06 → 2026-08-30
tmin00Zbilinear90d25 2 QC3.37 [1.72, 5.39]3.38+0.44 [-3.25, 3.51]4.64 [2.32, 6.63]28% [0%, 50%]48%60%+0.49+0.492026-08-06 → 2026-08-30
tmin00Zbilinear365d25 2 QC3.37 [1.59, 5.53]3.38+0.44 [-3.26, 3.85]4.64 [2.10, 6.75]28% [0%, 54%]48%60%+0.49+0.492026-08-06 → 2026-08-30
tmin00Zbilinearall25 2 QC3.37 [1.60, 5.65]3.38+0.44 [-3.40, 3.83]4.64 [2.11, 6.80]28% [0%, 54%]48%60%+0.49+0.492026-08-06 → 2026-08-30
tmin00Znearest30d25 2 QC3.35 [1.97, 5.09]3.33-0.07 [-2.89, 3.00]4.57 [2.50, 6.41]28% [17%, 36%]48%56%+0.50+0.502026-08-06 → 2026-08-30
tmin00Znearest90d25 2 QC3.35 [1.91, 5.26]3.33-0.07 [-3.56, 2.98]4.57 [2.46, 6.43]28% [14%, 37%]48%56%+0.50+0.502026-08-06 → 2026-08-30
tmin00Znearest365d25 2 QC3.35 [1.75, 5.30]3.33-0.07 [-3.51, 3.34]4.57 [2.25, 6.54]28% [17%, 38%]48%56%+0.50+0.502026-08-06 → 2026-08-30
tmin00Znearestall25 2 QC3.35 [1.77, 5.44]3.33-0.07 [-3.66, 3.22]4.57 [2.27, 6.59]28% [14%, 36%]48%56%+0.50+0.502026-08-06 → 2026-08-30
tmin12Zbilinear30d25 2 QC3.61 [2.40, 5.17]3.66+0.25 [-2.70, 3.62]4.57 [2.88, 6.18]16% [6%, 24%]28%56%+0.46+0.452026-08-06 → 2026-08-30
tmin12Zbilinear90d25 2 QC3.61 [2.35, 5.12]3.66+0.25 [-3.09, 3.64]4.57 [2.85, 6.13]16% [0%, 24%]28%56%+0.46+0.452026-08-06 → 2026-08-30
tmin12Zbilinear365d25 2 QC3.61 [2.16, 5.26]3.66+0.25 [-3.06, 3.98]4.57 [2.56, 6.22]16% [0%, 25%]28%56%+0.46+0.452026-08-06 → 2026-08-30
tmin12Zbilinearall25 2 QC3.61 [2.37, 5.32]3.66+0.25 [-3.15, 3.86]4.57 [2.79, 6.30]16% [0%, 25%]28%56%+0.46+0.452026-08-06 → 2026-08-30
tmin12Znearest30d25 2 QC3.79 [2.81, 5.00]3.66-0.47 [-3.36, 2.95]4.60 [3.37, 5.81]16% [6%, 24%]32%40%+0.43+0.452026-08-06 → 2026-08-30
tmin12Znearest90d25 2 QC3.79 [2.81, 4.94]3.66-0.47 [-3.63, 2.90]4.60 [3.30, 5.78]16% [0%, 24%]32%40%+0.43+0.452026-08-06 → 2026-08-30
tmin12Znearest365d25 2 QC3.79 [2.60, 4.99]3.66-0.47 [-3.57, 3.28]4.60 [3.07, 5.82]16% [0%, 25%]32%40%+0.43+0.452026-08-06 → 2026-08-30
tmin12Znearestall25 2 QC3.79 [2.76, 5.06]3.66-0.47 [-3.67, 3.12]4.60 [3.25, 5.93]16% [0%, 25%]32%40%+0.43+0.452026-08-06 → 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 NCEP GFS at KLAS, lead day 5, 00Z bilinear tmax+10+50-5-102026-08-06: +0.38 °F2026-08-07: -1.09 °F2026-08-08: -9.71 °F2026-08-09: -0.87 °F2026-08-10: -5.32 °F2026-08-11: +2.84 °F2026-08-12: +2.01 °F2026-08-13: +8.74 °F2026-08-14: +0.13 °F2026-08-15: +5.32 °F2026-08-16: -6.16 °F2026-08-17: -7.01 °F2026-08-18: -5.65 °F2026-08-19: -6.4 °F2026-08-20: -2.35 °F2026-08-21: -4.77 °F2026-08-22: -6.88 °F2026-08-23: -8.45 °F2026-08-24: -9.66 °F2026-08-25: -5.73 °F2026-08-26: -4.9 °F2026-08-27: -5.55 °F2026-08-28: -3.52 °F2026-08-29: -3.36 °F2026-08-30: -1.09 °F2026-08-062026-08-30°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 (25 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-1.09
2026-08-29-3.36
2026-08-28-3.52
2026-08-27-5.55
2026-08-26-4.90
2026-08-25-5.73
2026-08-24-9.66
2026-08-23-8.45
2026-08-22-6.88
2026-08-21-4.77
2026-08-20-2.35
2026-08-19-6.40
2026-08-18-5.65
2026-08-17-7.01
2026-08-16-6.16
2026-08-15+5.32
2026-08-14+0.13
2026-08-13+8.74
2026-08-12+2.01
2026-08-11+2.84
2026-08-10-5.32
2026-08-09-0.87
2026-08-08-9.71
2026-08-07-1.09
2026-08-06+0.38

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KLAS, lead day 5-10 to -9 °F: 2 days-9 to -8 °F: 1 day-8 to -7 °F: 1 day-7 to -6 °F: 3 days-6 to -5 °F: 4 days-5 to -4 °F: 2 days-4 to -3 °F: 2 days-3 to -2 °F: 1 day-2 to -1 °F: 2 days-1 to 0 °F: 1 day0 to 1 °F: 2 days1 to 2 °F: 0 days2 to 3 °F: 2 days3 to 4 °F: 0 days4 to 5 °F: 0 days5 to 6 °F: 1 day6 to 7 °F: 0 days7 to 8 °F: 0 days8 to 9 °F: 1 day9 to 10 °F: 0 daysdashed: P50 |e| 5.32 · P90 |e| 8.63 °F-100+10 °Fn = 25 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
-10.00-9.002
-9.00-8.001
-8.00-7.001
-7.00-6.003
-6.00-5.004
-5.00-4.002
-4.00-3.002
-3.00-2.001
-2.00-1.002
-1.00+0.001
+0.00+1.002
+1.00+2.000
+2.00+3.002
+3.00+4.000
+4.00+5.000
+5.00+6.001
+6.00+7.000
+7.00+8.000
+8.00+9.001
+9.00+10.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08254.72 -3.16

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-06 → 2026-08-30 25
NCEP GFS2026-08-06 → 2026-08-30 25
NCEP GFS2026-08-06 → 2026-08-30 25
NCEP GFS2026-08-06 → 2026-08-30 25

Compared with other models

Paired bootstrap on the days both models cover (90d, 00Z, bilinear, daily maximum). Negative means NCEP GFS has the lower MAE. "Distinguishable" means the 95 % interval excludes zero.

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 25 -1.33 [-2.63, -0.35] yes
GraphCast (IFS init) 25 -2.40 [-3.66, -1.27] yes
ECMWF IFS HRES 18 +1.51 [-1.60, 2.49] no
Persistence (baseline) 25 -2.28 [-6.08, 1.80] no

Cite this page

ShortCastCheck, KLAS gfs lead 5, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KLAS/model/gfs/lead/5/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KLAS (Las Vegas Harry Reid), model gfs, lead day 5. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KLAS/model/gfs/lead/5/

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