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

Atlanta Hartsfield · ECMWF IFS HRES · lead day 7

KATL · ifs_hres · 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, 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
tmax00Zbilinear30d18 1 QC3.48 [2.29, 4.54]3.48-0.29 [-2.52, 1.08]4.35 [2.91, 5.48]11% [0%, 25%]39%50%+0.04+0.032026-08-08 → 2026-08-30
tmax00Zbilinear90d18 1 QC3.48 [1.13, 4.60]3.48-0.29 [-2.90, 1.14]4.35 [1.13, 5.52]11% [0%, 26%]39%50%+0.04+0.032026-08-08 → 2026-08-30
tmax00Zbilinear365d18 1 QC3.48 [1.11, 4.62]3.48-0.29 [-2.97, 1.14]4.35 [1.11, 5.55]11% [0%, 29%]39%50%+0.04+0.032026-08-08 → 2026-08-30
tmax00Zbilinearall18 1 QC3.48 [1.11, 4.58]3.48-0.29 [-2.82, 1.07]4.35 [1.11, 5.60]11% [0%, 27%]39%50%+0.04+0.032026-08-08 → 2026-08-30
tmax00Znearest30d18 1 QC3.71 [2.51, 4.89]3.72-0.12 [-2.55, 1.47]4.63 [3.02, 5.86]22% [0%, 43%]39%50%-0.03-0.042026-08-08 → 2026-08-30
tmax00Znearest90d18 1 QC3.71 [1.69, 4.96]3.72-0.12 [-2.94, 1.69]4.63 [1.69, 5.90]22% [0%, 50%]39%50%-0.03-0.042026-08-08 → 2026-08-30
tmax00Znearest365d18 1 QC3.71 [1.69, 4.99]3.72-0.12 [-3.05, 1.69]4.63 [1.69, 5.96]22% [0%, 50%]39%50%-0.03-0.042026-08-08 → 2026-08-30
tmax00Znearestall18 1 QC3.71 [1.69, 4.92]3.72-0.12 [-2.80, 1.69]4.63 [1.69, 6.01]22% [0%, 50%]39%50%-0.03-0.042026-08-08 → 2026-08-30
tmax12Zbilinear30d17 1 QC3.66 [2.71, 4.55]3.82-1.59 [-3.63, 0.17]4.89 [3.49, 5.87]18% [0%, 40%]41%53%+0.01-0.052026-08-08 → 2026-08-30
tmax12Zbilinear90d17 1 QC3.66 [2.58, 4.59]3.82-1.59 [-3.83, 0.13]4.89 [3.38, 5.88]18% [0%, 50%]41%53%+0.01-0.052026-08-08 → 2026-08-30
tmax12Zbilinear365d17 1 QC3.66 [2.47, 4.66]3.82-1.59 [-3.83, 0.31]4.89 [3.43, 5.95]18% [0%, 50%]41%53%+0.01-0.052026-08-08 → 2026-08-30
tmax12Zbilinearall17 1 QC3.66 [2.39, 4.60]3.82-1.59 [-3.83, 0.11]4.89 [3.31, 5.87]18% [0%, 50%]41%53%+0.01-0.052026-08-08 → 2026-08-30
tmax12Znearest30d17 1 QC3.85 [2.89, 4.56]4.01-1.31 [-3.46, 0.62]4.93 [3.59, 5.80]18% [0%, 40%]29%53%-0.04-0.102026-08-08 → 2026-08-30
tmax12Znearest90d17 1 QC3.85 [2.63, 4.60]4.01-1.31 [-3.72, 0.60]4.93 [3.35, 5.81]18% [0%, 50%]29%53%-0.04-0.102026-08-08 → 2026-08-30
tmax12Znearest365d17 1 QC3.85 [2.57, 4.65]4.01-1.31 [-3.61, 0.80]4.93 [3.34, 5.90]18% [0%, 50%]29%53%-0.04-0.102026-08-08 → 2026-08-30
tmax12Znearestall17 1 QC3.85 [2.62, 4.62]4.01-1.31 [-3.61, 0.57]4.93 [3.32, 5.89]18% [0%, 50%]29%53%-0.04-0.102026-08-08 → 2026-08-30
tmin00Zbilinear30d18 1 QC2.74 [1.74, 3.71]2.48+1.18 [-0.57, 2.62]3.40 [1.89, 4.50]17% [0%, 32%]50%61%-0.15-0.042026-08-08 → 2026-08-30
tmin00Zbilinear90d18 1 QC2.74 [1.58, 3.59]2.48+1.18 [-0.93, 2.66]3.40 [1.74, 4.40]17% [0%, 33%]50%61%-0.15-0.042026-08-08 → 2026-08-30
tmin00Zbilinear365d18 1 QC2.74 [1.62, 3.69]2.48+1.18 [-0.95, 2.73]3.40 [1.69, 4.49]17% [0%, 35%]50%61%-0.15-0.042026-08-08 → 2026-08-30
tmin00Zbilinearall18 1 QC2.74 [1.55, 3.69]2.48+1.18 [-0.97, 2.63]3.40 [1.66, 4.48]17% [0%, 33%]50%61%-0.15-0.042026-08-08 → 2026-08-30
tmin00Znearest30d18 1 QC2.87 [1.80, 3.80]2.51+1.32 [-0.45, 2.72]3.48 [1.89, 4.53]11% [0%, 22%]44%61%-0.20-0.052026-08-08 → 2026-08-30
tmin00Znearest90d18 1 QC2.87 [1.59, 3.65]2.51+1.32 [-0.80, 2.77]3.48 [1.66, 4.46]11% [0%, 23%]44%61%-0.20-0.052026-08-08 → 2026-08-30
tmin00Znearest365d18 1 QC2.87 [1.60, 3.80]2.51+1.32 [-0.82, 2.81]3.48 [1.68, 4.58]11% [0%, 24%]44%61%-0.20-0.052026-08-08 → 2026-08-30
tmin00Znearestall18 1 QC2.87 [1.48, 3.78]2.51+1.32 [-0.86, 2.71]3.48 [1.59, 4.52]11% [0%, 24%]44%61%-0.20-0.052026-08-08 → 2026-08-30
tmin12Zbilinear30d17 1 QC1.82 [0.83, 2.63]1.64+1.18 [-0.40, 2.35]2.40 [1.14, 3.19]35% [7%, 67%]65%82%+0.26+0.332026-08-08 → 2026-08-30
tmin12Zbilinear90d17 1 QC1.82 [0.72, 2.60]1.64+1.18 [-0.62, 2.42]2.40 [1.01, 3.15]35% [7%, 75%]65%82%+0.26+0.332026-08-08 → 2026-08-30
tmin12Zbilinear365d17 1 QC1.82 [0.46, 2.71]1.64+1.18 [-0.56, 2.56]2.40 [0.63, 3.24]35% [0%, 76%]65%82%+0.26+0.332026-08-08 → 2026-08-30
tmin12Zbilinearall17 1 QC1.82 [0.58, 2.64]1.64+1.18 [-0.59, 2.50]2.40 [0.74, 3.17]35% [0%, 78%]65%82%+0.26+0.332026-08-08 → 2026-08-30
tmin12Znearest30d17 1 QC1.81 [0.84, 2.68]1.58+1.28 [-0.23, 2.39]2.37 [1.02, 3.19]35% [7%, 67%]71%82%+0.27+0.352026-08-08 → 2026-08-30
tmin12Znearest90d17 1 QC1.81 [0.68, 2.64]1.58+1.28 [-0.39, 2.44]2.37 [0.88, 3.16]35% [7%, 75%]71%82%+0.27+0.352026-08-08 → 2026-08-30
tmin12Znearest365d17 1 QC1.81 [0.66, 2.76]1.58+1.28 [-0.36, 2.60]2.37 [0.78, 3.24]35% [0%, 76%]71%82%+0.27+0.352026-08-08 → 2026-08-30
tmin12Znearestall17 1 QC1.81 [0.70, 2.69]1.58+1.28 [-0.37, 2.55]2.37 [0.82, 3.19]35% [0%, 78%]71%82%+0.27+0.352026-08-08 → 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 IFS HRES at KATL, lead day 7, 00Z bilinear tmax+20+100-10-202026-08-08: +1.05 °F2026-08-14: -7.85 °F2026-08-15: -1.62 °F2026-08-16: +2.38 °F2026-08-17: +1.6 °F2026-08-18: +5.48 °F2026-08-19: +3.75 °F2026-08-20: -0.04 °F2026-08-21: -0.71 °F2026-08-22: -2.62 °F2026-08-23: -3.46 °F2026-08-24: +4.1 °F2026-08-25: +5.01 °F2026-08-26: +5.39 °F2026-08-27: -5.13 °F2026-08-28: -10.22 °F2026-08-29: -1.15 °F2026-08-30: -1.11 °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
2026-08-30-1.11
2026-08-29-1.15
2026-08-28-10.22
2026-08-27-5.13
2026-08-26+5.39
2026-08-25+5.01
2026-08-24+4.10
2026-08-23-3.46
2026-08-22-2.62
2026-08-21-0.71
2026-08-20-0.04
2026-08-19+3.75
2026-08-18+5.48
2026-08-17+1.60
2026-08-16+2.38
2026-08-15-1.62
2026-08-14-7.85
2026-08-13—
2026-08-12—
2026-08-11—
2026-08-10—
2026-08-09—
2026-08-08+1.05

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KATL, lead day 7-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 0 days-12 to -10 °F: 1 day-10 to -8 °F: 0 days-8 to -6 °F: 1 day-6 to -4 °F: 1 day-4 to -2 °F: 2 days-2 to 0 °F: 5 days0 to 2 °F: 2 days2 to 4 °F: 2 days4 to 6 °F: 4 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| 3.04 · P90 |e| 6.19 °F-200+20 °Fn = 18 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
-18.00-16.000
-16.00-14.000
-14.00-12.000
-12.00-10.001
-10.00-8.000
-8.00-6.001
-6.00-4.001
-4.00-2.002
-2.00+0.005
+0.00+2.002
+2.00+4.002
+4.00+6.004
+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
2026-08183.48 -0.29

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-08 → 2026-08-30 18
ECMWF IFS HRES2026-08-08 → 2026-08-30 18
ECMWF IFS HRES2026-08-08 → 2026-08-30 17
ECMWF IFS HRES2026-08-08 → 2026-08-30 17

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 18 -0.86 [-3.47, -0.08] yes
NCEP GFS 18 +0.34 [-2.24, 2.61] no
GraphCast (IFS init) 18 -1.53 [-6.36, -0.21] yes
Persistence (baseline) 18 -0.13 [-3.39, 0.63] no

Cite this page

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

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