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

Dallas-Fort Worth · NCEP GFS · lead day 4

KDFW · gfs · lead 4

Target day = initialization date + 4 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, 1 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
tmax00Zbilinear30d26 1 QC1.88 [1.38, 2.38]1.59+1.07 [0.44, 1.59]2.53 [1.58, 3.47]23% [7%, 41%]65%88%+0.29+0.382026-08-05 → 2026-08-30
tmax00Zbilinear90d26 1 QC1.88 [1.31, 2.38]1.59+1.07 [0.34, 1.64]2.53 [1.52, 3.45]23% [6%, 45%]65%88%+0.29+0.382026-08-05 → 2026-08-30
tmax00Zbilinear365d26 1 QC1.88 [1.27, 2.41]1.59+1.07 [0.29, 1.70]2.53 [1.46, 3.56]23% [5%, 45%]65%88%+0.29+0.382026-08-05 → 2026-08-30
tmax00Zbilinearall26 1 QC1.88 [1.27, 2.48]1.59+1.07 [0.27, 1.66]2.53 [1.41, 3.56]23% [0%, 43%]65%88%+0.29+0.382026-08-05 → 2026-08-30
tmax00Znearest30d26 1 QC1.79 [1.23, 2.36]1.68+1.15 [0.46, 1.71]2.63 [1.50, 3.71]38% [22%, 56%]65%85%+0.33+0.352026-08-05 → 2026-08-30
tmax00Znearest90d26 1 QC1.79 [1.16, 2.37]1.68+1.15 [0.36, 1.78]2.63 [1.42, 3.72]38% [21%, 58%]65%85%+0.33+0.352026-08-05 → 2026-08-30
tmax00Znearest365d26 1 QC1.79 [1.08, 2.42]1.68+1.15 [0.29, 1.83]2.63 [1.34, 3.84]38% [21%, 59%]65%85%+0.33+0.352026-08-05 → 2026-08-30
tmax00Znearestall26 1 QC1.79 [1.04, 2.47]1.68+1.15 [0.19, 1.78]2.63 [1.28, 3.85]38% [21%, 59%]65%85%+0.33+0.352026-08-05 → 2026-08-30
tmax12Zbilinear30d26 1 QC2.12 [1.34, 2.96]1.68+1.17 [0.17, 1.88]2.88 [1.61, 3.85]27% [14%, 44%]62%81%+0.20+0.352026-08-05 → 2026-08-30
tmax12Zbilinear90d26 1 QC2.12 [1.19, 2.96]1.68+1.17 [0.03, 1.93]2.88 [1.46, 3.90]27% [14%, 50%]62%81%+0.20+0.352026-08-05 → 2026-08-30
tmax12Zbilinear365d26 1 QC2.12 [1.18, 3.02]1.68+1.17 [-0.28, 1.99]2.88 [1.44, 4.01]27% [14%, 50%]62%81%+0.20+0.352026-08-05 → 2026-08-30
tmax12Zbilinearall26 1 QC2.12 [1.04, 3.14]1.68+1.17 [0.07, 1.97]2.88 [1.33, 4.08]27% [14%, 50%]62%81%+0.20+0.352026-08-05 → 2026-08-30
tmax12Znearest30d26 1 QC2.08 [1.35, 2.82]1.72+1.14 [0.10, 1.85]2.81 [1.64, 3.72]27% [17%, 40%]65%81%+0.22+0.342026-08-05 → 2026-08-30
tmax12Znearest90d26 1 QC2.08 [1.24, 2.80]1.72+1.14 [-0.04, 1.90]2.81 [1.49, 3.79]27% [15%, 43%]65%81%+0.22+0.342026-08-05 → 2026-08-30
tmax12Znearest365d26 1 QC2.08 [1.20, 2.88]1.72+1.14 [-0.35, 1.97]2.81 [1.48, 3.88]27% [14%, 43%]65%81%+0.22+0.342026-08-05 → 2026-08-30
tmax12Znearestall26 1 QC2.08 [1.12, 3.06]1.72+1.14 [-0.01, 1.95]2.81 [1.32, 3.97]27% [14%, 45%]65%81%+0.22+0.342026-08-05 → 2026-08-30
tmin00Zbilinear30d26 1 QC3.12 [2.66, 3.73]1.38+3.12 [2.66, 3.73]3.50 [3.09, 4.03]8% [0%, 17%]31%50%-0.08+0.522026-08-05 → 2026-08-30
tmin00Zbilinear90d26 1 QC3.12 [2.68, 3.84]1.38+3.12 [2.68, 3.84]3.50 [3.08, 4.07]8% [0%, 18%]31%50%-0.08+0.522026-08-05 → 2026-08-30
tmin00Zbilinear365d26 1 QC3.12 [2.68, 3.89]1.38+3.12 [2.68, 3.89]3.50 [3.08, 4.09]8% [0%, 19%]31%50%-0.08+0.522026-08-05 → 2026-08-30
tmin00Zbilinearall26 1 QC3.12 [2.62, 3.84]1.38+3.12 [2.62, 3.84]3.50 [2.99, 4.09]8% [0%, 18%]31%50%-0.08+0.522026-08-05 → 2026-08-30
tmin00Znearest30d26 1 QC3.90 [3.45, 4.48]1.36+3.90 [3.45, 4.48]4.22 [3.78, 4.73]0% [0%, 0%]12%27%-0.35+0.522026-08-05 → 2026-08-30
tmin00Znearest90d26 1 QC3.90 [3.44, 4.56]1.36+3.90 [3.44, 4.56]4.22 [3.78, 4.76]0% [0%, 0%]12%27%-0.35+0.522026-08-05 → 2026-08-30
tmin00Znearest365d26 1 QC3.90 [3.44, 4.62]1.36+3.90 [3.44, 4.62]4.22 [3.78, 4.83]0% [0%, 0%]12%27%-0.35+0.522026-08-05 → 2026-08-30
tmin00Znearestall26 1 QC3.90 [3.38, 4.60]1.36+3.90 [3.38, 4.60]4.22 [3.68, 4.78]0% [0%, 0%]12%27%-0.35+0.522026-08-05 → 2026-08-30
tmin12Zbilinear30d26 1 QC3.21 [2.80, 3.73]1.17+3.20 [2.79, 3.73]3.53 [3.10, 3.97]4% [0%, 11%]27%42%-0.11+0.592026-08-05 → 2026-08-30
tmin12Zbilinear90d26 1 QC3.21 [2.79, 3.78]1.17+3.20 [2.78, 3.78]3.53 [3.08, 4.01]4% [0%, 11%]27%42%-0.11+0.592026-08-05 → 2026-08-30
tmin12Zbilinear365d26 1 QC3.21 [2.80, 3.80]1.17+3.20 [2.80, 3.80]3.53 [3.09, 4.04]4% [0%, 12%]27%42%-0.11+0.592026-08-05 → 2026-08-30
tmin12Zbilinearall26 1 QC3.21 [2.69, 3.78]1.17+3.20 [2.69, 3.78]3.53 [2.93, 4.00]4% [0%, 12%]27%42%-0.11+0.592026-08-05 → 2026-08-30
tmin12Znearest30d26 1 QC3.76 [3.40, 4.21]1.03+3.76 [3.40, 4.21]4.00 [3.56, 4.42]4% [0%, 11%]8%31%-0.30+0.642026-08-05 → 2026-08-30
tmin12Znearest90d26 1 QC3.76 [3.41, 4.24]1.03+3.76 [3.41, 4.24]4.00 [3.58, 4.48]4% [0%, 11%]8%31%-0.30+0.642026-08-05 → 2026-08-30
tmin12Znearest365d26 1 QC3.76 [3.39, 4.27]1.03+3.76 [3.39, 4.27]4.00 [3.53, 4.52]4% [0%, 12%]8%31%-0.30+0.642026-08-05 → 2026-08-30
tmin12Znearestall26 1 QC3.76 [3.32, 4.26]1.03+3.76 [3.32, 4.26]4.00 [3.49, 4.46]4% [0%, 12%]8%31%-0.30+0.642026-08-05 → 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 KDFW, lead day 4, 00Z bilinear tmax+10+50-5-102026-08-05: +1.01 °F2026-08-06: +1.99 °F2026-08-07: -2.55 °F2026-08-08: +0.57 °F2026-08-09: -1.41 °F2026-08-10: +3.42 °F2026-08-11: +2.35 °F2026-08-12: +2.1 °F2026-08-13: +1.37 °F2026-08-14: +1.64 °F2026-08-15: +2.1 °F2026-08-16: +1 °F2026-08-17: -1.37 °F2026-08-18: +1.11 °F2026-08-19: +1.98 °F2026-08-20: +0.5 °F2026-08-21: +8.95 °F2026-08-22: +0.31 °F2026-08-23: -1.1 °F2026-08-24: -2.76 °F2026-08-25: +4.09 °F2026-08-26: +2.4 °F2026-08-27: -0.41 °F2026-08-28: +0.34 °F2026-08-29: -0.94 °F2026-08-30: +1.05 °F2026-08-052026-08-30°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 (26 days, newest first) · download CSV
Climatological dayError °F
2026-08-30+1.05
2026-08-29-0.94
2026-08-28+0.34
2026-08-27-0.41
2026-08-26+2.40
2026-08-25+4.09
2026-08-24-2.76
2026-08-23-1.10
2026-08-22+0.31
2026-08-21+8.95
2026-08-20+0.50
2026-08-19+1.98
2026-08-18+1.11
2026-08-17-1.37
2026-08-16+1.00
2026-08-15+2.10
2026-08-14+1.64
2026-08-13+1.37
2026-08-12+2.10
2026-08-11+2.35
2026-08-10+3.42
2026-08-09-1.41
2026-08-08+0.57
2026-08-07-2.55
2026-08-06+1.99
2026-08-05+1.01

Error distribution

Distribution of the signed daily error in °F for NCEP GFS at KDFW, lead day 4-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 0 days-6 to -5 °F: 0 days-5 to -4 °F: 0 days-4 to -3 °F: 0 days-3 to -2 °F: 2 days-2 to -1 °F: 3 days-1 to 0 °F: 2 days0 to 1 °F: 4 days1 to 2 °F: 8 days2 to 3 °F: 4 days3 to 4 °F: 1 day4 to 5 °F: 1 day5 to 6 °F: 0 days6 to 7 °F: 0 days7 to 8 °F: 0 days8 to 9 °F: 1 day9 to 10 °F: 0 daysdashed: P50 |e| 1.39 · P90 |e| 3.09 °F-100+10 °Fn = 26 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
-10.00-9.000
-9.00-8.000
-8.00-7.000
-7.00-6.000
-6.00-5.000
-5.00-4.000
-4.00-3.000
-3.00-2.002
-2.00-1.003
-1.00+0.002
+0.00+1.004
+1.00+2.008
+2.00+3.004
+3.00+4.001
+4.00+5.001
+5.00+6.000
+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
2026-08261.88 +1.07

Availability

ModelScored period DaysCoverage
NCEP GFS2026-08-05 → 2026-08-30 26
NCEP GFS2026-08-05 → 2026-08-30 26
NCEP GFS2026-08-05 → 2026-08-30 26
NCEP GFS2026-08-05 → 2026-08-30 26

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 26 -1.33 [-2.63, -0.42] yes
GraphCast (IFS init) 25 -5.22 [-6.97, -3.80] yes
ECMWF IFS HRES 20 -0.42 [-1.24, 0.47] no
Persistence (baseline) 26 -0.78 [-2.17, 0.32] no

Cite this page

ShortCastCheck, KDFW gfs lead 4, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KDFW/model/gfs/lead/4/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KDFW (Dallas-Fort Worth), model gfs, lead day 4. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KDFW/model/gfs/lead/4/

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