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

Atlanta Hartsfield · ECMWF IFS HRES · lead day 6

KATL · ifs_hres · 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, ifs-gpid161, 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
tmax00Zbilinear30d19 1 QC3.12 [2.44, 3.83]3.13-0.12 [-1.98, 1.58]3.94 [3.15, 4.60]16% [0%, 36%]42%63%-0.12-0.132026-08-07 → 2026-08-30
tmax00Zbilinear90d19 1 QC3.12 [2.43, 4.12]3.13-0.12 [-2.23, 1.88]3.94 [3.18, 4.61]16% [0%, 38%]42%63%-0.12-0.132026-08-07 → 2026-08-30
tmax00Zbilinear365d19 1 QC3.12 [2.38, 4.12]3.13-0.12 [-2.56, 1.92]3.94 [3.14, 4.63]16% [0%, 38%]42%63%-0.12-0.132026-08-07 → 2026-08-30
tmax00Zbilinearall19 1 QC3.12 [2.30, 4.09]3.13-0.12 [-2.31, 1.80]3.94 [2.92, 4.58]16% [0%, 38%]42%63%-0.12-0.132026-08-07 → 2026-08-30
tmax00Znearest30d19 1 QC3.35 [2.72, 3.98]3.33+0.15 [-1.93, 1.94]4.07 [3.28, 4.77]11% [0%, 20%]42%47%-0.20-0.202026-08-07 → 2026-08-30
tmax00Znearest90d19 1 QC3.35 [2.71, 4.12]3.33+0.15 [-2.10, 2.34]4.07 [3.30, 4.80]11% [0%, 22%]42%47%-0.20-0.202026-08-07 → 2026-08-30
tmax00Znearest365d19 1 QC3.35 [2.65, 4.12]3.33+0.15 [-2.55, 2.30]4.07 [3.24, 4.83]11% [0%, 22%]42%47%-0.20-0.202026-08-07 → 2026-08-30
tmax00Znearestall19 1 QC3.35 [2.62, 4.12]3.33+0.15 [-2.25, 2.20]4.07 [3.09, 4.79]11% [0%, 22%]42%47%-0.20-0.202026-08-07 → 2026-08-30
tmax12Zbilinear30d19 1 QC3.18 [2.15, 4.13]3.33-0.68 [-3.04, 1.55]3.98 [2.65, 4.94]16% [6%, 38%]37%63%-0.14-0.202026-08-07 → 2026-08-30
tmax12Zbilinear90d19 1 QC3.18 [1.56, 4.27]3.33-0.68 [-3.26, 1.68]3.98 [1.96, 5.05]16% [5%, 50%]37%63%-0.14-0.202026-08-07 → 2026-08-30
tmax12Zbilinear365d19 1 QC3.18 [1.84, 4.42]3.33-0.68 [-3.44, 1.97]3.98 [2.19, 5.26]16% [0%, 50%]37%63%-0.14-0.202026-08-07 → 2026-08-30
tmax12Zbilinearall19 1 QC3.18 [1.66, 4.32]3.33-0.68 [-3.50, 1.45]3.98 [1.95, 5.14]16% [0%, 50%]37%63%-0.14-0.202026-08-07 → 2026-08-30
tmax12Znearest30d19 1 QC2.97 [2.17, 3.55]2.99-0.13 [-2.35, 1.86]3.50 [2.60, 4.10]16% [0%, 50%]37%58%-0.06-0.082026-08-07 → 2026-08-30
tmax12Znearest90d19 1 QC2.97 [1.43, 3.67]2.99-0.13 [-2.68, 2.00]3.50 [1.78, 4.20]16% [0%, 67%]37%58%-0.06-0.082026-08-07 → 2026-08-30
tmax12Znearest365d19 1 QC2.97 [1.66, 3.73]2.99-0.13 [-2.65, 2.24]3.50 [1.87, 4.29]16% [0%, 50%]37%58%-0.06-0.082026-08-07 → 2026-08-30
tmax12Znearestall19 1 QC2.97 [1.38, 3.68]2.99-0.13 [-2.79, 1.85]3.50 [1.68, 4.22]16% [0%, 60%]37%58%-0.06-0.082026-08-07 → 2026-08-30
tmin00Zbilinear30d19 1 QC2.31 [1.64, 3.06]1.98+1.32 [-0.34, 2.68]2.81 [1.87, 3.63]21% [8%, 38%]47%74%+0.12+0.252026-08-07 → 2026-08-30
tmin00Zbilinear90d19 1 QC2.31 [1.63, 3.10]1.98+1.32 [-0.67, 2.94]2.81 [1.82, 3.64]21% [0%, 40%]47%74%+0.12+0.252026-08-07 → 2026-08-30
tmin00Zbilinear365d19 1 QC2.31 [1.60, 3.11]1.98+1.32 [-0.69, 2.94]2.81 [1.81, 3.68]21% [0%, 42%]47%74%+0.12+0.252026-08-07 → 2026-08-30
tmin00Zbilinearall19 1 QC2.31 [1.58, 3.09]1.98+1.32 [-0.60, 2.94]2.81 [1.80, 3.65]21% [0%, 40%]47%74%+0.12+0.252026-08-07 → 2026-08-30
tmin00Znearest30d19 1 QC2.41 [1.62, 3.25]2.10+1.51 [-0.21, 2.98]2.97 [1.95, 3.82]26% [10%, 44%]42%68%+0.08+0.202026-08-07 → 2026-08-30
tmin00Znearest90d19 1 QC2.41 [1.53, 3.43]2.10+1.51 [-0.56, 3.43]2.97 [1.84, 3.81]26% [0%, 45%]42%68%+0.08+0.202026-08-07 → 2026-08-30
tmin00Znearest365d19 1 QC2.41 [1.51, 3.43]2.10+1.51 [-0.60, 3.43]2.97 [1.82, 3.86]26% [0%, 47%]42%68%+0.08+0.202026-08-07 → 2026-08-30
tmin00Znearestall19 1 QC2.41 [1.48, 3.43]2.10+1.51 [-0.52, 3.43]2.97 [1.77, 3.81]26% [0%, 50%]42%68%+0.08+0.202026-08-07 → 2026-08-30
tmin12Zbilinear30d19 1 QC2.29 [1.11, 3.09]2.07+1.44 [-0.23, 2.75]2.82 [1.49, 3.56]42% [23%, 73%]42%68%+0.13+0.222026-08-07 → 2026-08-30
tmin12Zbilinear90d19 1 QC2.29 [0.89, 3.18]2.07+1.44 [-0.51, 2.87]2.82 [1.17, 3.61]42% [20%, 83%]42%68%+0.13+0.222026-08-07 → 2026-08-30
tmin12Zbilinear365d19 1 QC2.29 [0.90, 3.19]2.07+1.44 [-0.53, 3.04]2.82 [1.20, 3.62]42% [19%, 83%]42%68%+0.13+0.222026-08-07 → 2026-08-30
tmin12Zbilinearall19 1 QC2.29 [0.85, 3.15]2.07+1.44 [-0.51, 2.83]2.82 [1.12, 3.58]42% [21%, 86%]42%68%+0.13+0.222026-08-07 → 2026-08-30
tmin12Znearest30d19 1 QC2.32 [1.18, 3.13]2.03+1.48 [-0.13, 2.77]2.81 [1.39, 3.54]32% [8%, 60%]42%79%+0.12+0.232026-08-07 → 2026-08-30
tmin12Znearest90d19 1 QC2.32 [1.03, 3.19]2.03+1.48 [-0.32, 2.90]2.81 [1.13, 3.58]32% [0%, 62%]42%79%+0.12+0.232026-08-07 → 2026-08-30
tmin12Znearest365d19 1 QC2.32 [1.03, 3.20]2.03+1.48 [-0.39, 3.04]2.81 [1.11, 3.61]32% [0%, 67%]42%79%+0.12+0.232026-08-07 → 2026-08-30
tmin12Znearestall19 1 QC2.32 [1.03, 3.16]2.03+1.48 [-0.39, 2.88]2.81 [1.08, 3.56]32% [0%, 64%]42%79%+0.12+0.232026-08-07 → 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 IFS HRES at KATL, lead day 6, 00Z bilinear tmax+10+50-5-102026-08-07: +4.12 °F2026-08-13: -6.56 °F2026-08-14: -2.21 °F2026-08-15: -1.51 °F2026-08-16: +1.05 °F2026-08-17: +4.15 °F2026-08-18: +8.9 °F2026-08-19: -0.37 °F2026-08-20: +0.25 °F2026-08-21: +0.53 °F2026-08-22: -5.84 °F2026-08-23: +2.78 °F2026-08-24: +2.82 °F2026-08-25: +1.03 °F2026-08-26: +2.92 °F2026-08-27: -5.02 °F2026-08-28: -6.46 °F2026-08-29: -1.15 °F2026-08-30: -1.66 °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
2026-08-30-1.66
2026-08-29-1.15
2026-08-28-6.46
2026-08-27-5.02
2026-08-26+2.92
2026-08-25+1.03
2026-08-24+2.82
2026-08-23+2.78
2026-08-22-5.84
2026-08-21+0.53
2026-08-20+0.25
2026-08-19-0.37
2026-08-18+8.90
2026-08-17+4.15
2026-08-16+1.05
2026-08-15-1.51
2026-08-14-2.21
2026-08-13-6.56
2026-08-12—
2026-08-11—
2026-08-10—
2026-08-09—
2026-08-08—
2026-08-07+4.12

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KATL, lead day 6-10 to -9 °F: 0 days-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 2 days-6 to -5 °F: 2 days-5 to -4 °F: 0 days-4 to -3 °F: 0 days-3 to -2 °F: 1 day-2 to -1 °F: 3 days-1 to 0 °F: 1 day0 to 1 °F: 2 days1 to 2 °F: 2 days2 to 3 °F: 3 days3 to 4 °F: 0 days4 to 5 °F: 2 days5 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| 2.78 · P90 |e| 6.48 °F-100+10 °Fn = 19 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
-7.00-6.002
-6.00-5.002
-5.00-4.000
-4.00-3.000
-3.00-2.001
-2.00-1.003
-1.00+0.001
+0.00+1.002
+1.00+2.002
+2.00+3.003
+3.00+4.000
+4.00+5.002
+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
2026-08193.12 -0.12

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-07 → 2026-08-30 19
ECMWF IFS HRES2026-08-07 → 2026-08-30 19
ECMWF IFS HRES2026-08-07 → 2026-08-30 19
ECMWF IFS HRES2026-08-07 → 2026-08-30 19

Compared with other models

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

Other modelCommon days MAE difference °FDistinguishable
ECMWF AIFS Single 19 -1.32 [-2.35, 0.51] no
NCEP GFS 19 -2.35 [-3.43, -1.21] yes
GraphCast (IFS init) 19 -1.90 [-4.07, -0.26] yes
Persistence (baseline) 19 +0.33 [-0.48, 1.61] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KATL (Atlanta Hartsfield), model ifs_hres, 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/KATL/model/ifs_hres/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