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

Washington Reagan · ECMWF IFS HRES · lead day 5

KDCA · ifs_hres · 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, 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 QC3.63 [2.19, 4.47]3.15-2.75 [-4.04, -0.61]4.65 [2.70, 5.50]17% [0%, 42%]44%61%+0.29+0.402026-08-06 → 2026-08-30
tmax00Zbilinear90d18 1 QC3.63 [1.72, 4.53]3.15-2.75 [-4.15, -0.33]4.65 [2.02, 5.52]17% [0%, 46%]44%61%+0.29+0.402026-08-06 → 2026-08-30
tmax00Zbilinear365d18 1 QC3.63 [1.61, 4.61]3.15-2.75 [-4.31, -0.19]4.65 [1.81, 5.59]17% [0%, 50%]44%61%+0.29+0.402026-08-06 → 2026-08-30
tmax00Zbilinearall18 1 QC3.63 [1.72, 4.52]3.15-2.75 [-4.27, -0.23]4.65 [1.96, 5.51]17% [0%, 47%]44%61%+0.29+0.402026-08-06 → 2026-08-30
tmax00Znearest30d18 1 QC3.56 [2.34, 4.23]3.17-2.28 [-3.73, 0.04]4.37 [2.57, 5.08]6% [0%, 13%]39%67%+0.30+0.392026-08-06 → 2026-08-30
tmax00Znearest90d18 1 QC3.56 [2.06, 4.28]3.17-2.28 [-3.79, 0.26]4.37 [2.17, 5.07]6% [0%, 14%]39%67%+0.30+0.392026-08-06 → 2026-08-30
tmax00Znearest365d18 1 QC3.56 [1.98, 4.32]3.17-2.28 [-4.00, 0.49]4.37 [2.05, 5.13]6% [0%, 14%]39%67%+0.30+0.392026-08-06 → 2026-08-30
tmax00Znearestall18 1 QC3.56 [1.98, 4.27]3.17-2.28 [-3.93, 0.41]4.37 [2.11, 5.05]6% [0%, 14%]39%67%+0.30+0.392026-08-06 → 2026-08-30
tmax12Zbilinear30d20 1 QC3.57 [2.95, 4.04]2.64-2.34 [-3.52, -0.67]4.11 [3.28, 4.62]10% [0%, 24%]10%40%+0.26+0.462026-08-06 → 2026-08-30
tmax12Zbilinear90d20 1 QC3.57 [2.88, 4.00]2.64-2.34 [-3.68, -0.44]4.11 [3.18, 4.59]10% [0%, 25%]10%40%+0.26+0.462026-08-06 → 2026-08-30
tmax12Zbilinear365d20 1 QC3.57 [2.86, 4.02]2.64-2.34 [-3.72, -0.11]4.11 [3.20, 4.61]10% [0%, 27%]10%40%+0.26+0.462026-08-06 → 2026-08-30
tmax12Zbilinearall20 1 QC3.57 [2.89, 4.01]2.64-2.34 [-3.69, -0.32]4.11 [3.21, 4.63]10% [0%, 25%]10%40%+0.26+0.462026-08-06 → 2026-08-30
tmax12Znearest30d20 1 QC3.30 [2.69, 3.79]2.85-1.66 [-2.91, -0.21]3.77 [2.94, 4.30]10% [0%, 24%]20%65%+0.32+0.412026-08-06 → 2026-08-30
tmax12Znearest90d20 1 QC3.30 [2.63, 3.77]2.85-1.66 [-3.11, 0.06]3.77 [2.72, 4.27]10% [0%, 25%]20%65%+0.32+0.412026-08-06 → 2026-08-30
tmax12Znearest365d20 1 QC3.30 [2.67, 3.80]2.85-1.66 [-3.22, 0.16]3.77 [2.72, 4.30]10% [0%, 27%]20%65%+0.32+0.412026-08-06 → 2026-08-30
tmax12Znearestall20 1 QC3.30 [2.61, 3.79]2.85-1.66 [-3.19, 0.10]3.77 [2.72, 4.33]10% [0%, 25%]20%65%+0.32+0.412026-08-06 → 2026-08-30
tmin00Zbilinear30d18 1 QC2.51 [1.37, 3.34]2.55-0.20 [-2.36, 1.69]3.20 [1.96, 4.17]33% [22%, 60%]50%56%+0.45+0.452026-08-06 → 2026-08-30
tmin00Zbilinear90d18 1 QC2.51 [0.81, 3.30]2.55-0.20 [-2.56, 1.77]3.20 [1.32, 4.23]33% [21%, 73%]50%56%+0.45+0.452026-08-06 → 2026-08-30
tmin00Zbilinear365d18 1 QC2.51 [0.70, 3.37]2.55-0.20 [-2.61, 1.98]3.20 [0.92, 4.25]33% [21%, 80%]50%56%+0.45+0.452026-08-06 → 2026-08-30
tmin00Zbilinearall18 1 QC2.51 [0.56, 3.34]2.55-0.20 [-2.64, 1.90]3.20 [0.81, 4.31]33% [22%, 84%]50%56%+0.45+0.452026-08-06 → 2026-08-30
tmin00Znearest30d18 1 QC2.59 [1.49, 3.49]2.61-0.20 [-2.43, 1.78]3.22 [1.94, 4.18]33% [23%, 58%]44%61%+0.43+0.442026-08-06 → 2026-08-30
tmin00Znearest90d18 1 QC2.59 [0.90, 3.49]2.61-0.20 [-2.58, 1.90]3.22 [1.11, 4.19]33% [22%, 72%]44%61%+0.43+0.442026-08-06 → 2026-08-30
tmin00Znearest365d18 1 QC2.59 [0.54, 3.56]2.61-0.20 [-2.68, 2.06]3.22 [0.72, 4.29]33% [22%, 85%]44%61%+0.43+0.442026-08-06 → 2026-08-30
tmin00Znearestall18 1 QC2.59 [0.51, 3.53]2.61-0.20 [-2.69, 2.03]3.22 [0.70, 4.32]33% [22%, 84%]44%61%+0.43+0.442026-08-06 → 2026-08-30
tmin12Zbilinear30d20 1 QC3.25 [1.95, 4.23]3.23-0.28 [-2.09, 1.71]3.84 [2.26, 4.77]10% [0%, 22%]40%45%+0.24+0.262026-08-06 → 2026-08-30
tmin12Zbilinear90d20 1 QC3.25 [1.64, 4.19]3.23-0.28 [-2.16, 1.90]3.84 [1.98, 4.75]10% [0%, 25%]40%45%+0.24+0.262026-08-06 → 2026-08-30
tmin12Zbilinear365d20 1 QC3.25 [1.51, 4.29]3.23-0.28 [-2.13, 2.07]3.84 [1.73, 4.82]10% [0%, 25%]40%45%+0.24+0.262026-08-06 → 2026-08-30
tmin12Zbilinearall20 1 QC3.25 [1.26, 4.25]3.23-0.28 [-2.18, 2.15]3.84 [1.26, 4.72]10% [0%, 25%]40%45%+0.24+0.262026-08-06 → 2026-08-30
tmin12Znearest30d20 1 QC3.24 [2.01, 4.10]3.22-0.19 [-1.97, 1.80]3.78 [2.26, 4.64]10% [0%, 22%]30%50%+0.25+0.262026-08-06 → 2026-08-30
tmin12Znearest90d20 1 QC3.24 [1.54, 4.10]3.22-0.19 [-2.01, 2.02]3.78 [1.88, 4.65]10% [0%, 25%]30%50%+0.25+0.262026-08-06 → 2026-08-30
tmin12Znearest365d20 1 QC3.24 [1.40, 4.20]3.22-0.19 [-1.98, 2.18]3.78 [1.57, 4.73]10% [0%, 25%]30%50%+0.25+0.262026-08-06 → 2026-08-30
tmin12Znearestall20 1 QC3.24 [1.08, 4.10]3.22-0.19 [-2.03, 2.27]3.78 [1.10, 4.63]10% [0%, 25%]30%50%+0.25+0.262026-08-06 → 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 ECMWF IFS HRES at KDCA, lead day 5, 00Z bilinear tmax+20+100-10-202026-08-06: -3.36 °F2026-08-12: +0.85 °F2026-08-13: +0.71 °F2026-08-14: +1.97 °F2026-08-16: +2.02 °F2026-08-17: -10.88 °F2026-08-19: +1.76 °F2026-08-20: -6.96 °F2026-08-21: -2.86 °F2026-08-22: -1.12 °F2026-08-23: -6.34 °F2026-08-24: -1.78 °F2026-08-25: -8.43 °F2026-08-26: -5.76 °F2026-08-27: -5.7 °F2026-08-28: -2.44 °F2026-08-29: +0.6 °F2026-08-30: -1.71 °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
2026-08-30-1.71
2026-08-29+0.60
2026-08-28-2.44
2026-08-27-5.70
2026-08-26-5.76
2026-08-25-8.43
2026-08-24-1.78
2026-08-23-6.34
2026-08-22-1.12
2026-08-21-2.86
2026-08-20-6.96
2026-08-19+1.76
2026-08-18—
2026-08-17-10.88
2026-08-16+2.02
2026-08-15—
2026-08-14+1.97
2026-08-13+0.71
2026-08-12+0.85
2026-08-11—
2026-08-10—
2026-08-09—
2026-08-08—
2026-08-07—
2026-08-06-3.36

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KDCA, lead day 5-20 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: 1 day-8 to -6 °F: 2 days-6 to -4 °F: 2 days-4 to -2 °F: 3 days-2 to 0 °F: 3 days0 to 2 °F: 5 days2 to 4 °F: 1 day4 to 6 °F: 0 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| 2.23 · P90 |e| 7.4 °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
-10.00-8.001
-8.00-6.002
-6.00-4.002
-4.00-2.003
-2.00+0.003
+0.00+2.005
+2.00+4.001
+4.00+6.000
+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
2026-08183.63 -2.75

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-06 → 2026-08-30 18
ECMWF IFS HRES2026-08-06 → 2026-08-30 18
ECMWF IFS HRES2026-08-06 → 2026-08-30 20
ECMWF IFS HRES2026-08-06 → 2026-08-30 20

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 -0.14 [-1.52, 1.42] no
NCEP GFS 18 -1.05 [-2.43, 0.15] no
GraphCast (IFS init) 18 -1.04 [-2.41, 0.55] no
Persistence (baseline) 18 -1.49 [-3.02, 0.43] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KDCA (Washington Reagan), model ifs_hres, 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/KDCA/model/ifs_hres/lead/5/

Accessed2026-08-31 (data through 2026-08-30; page built 2026-08-31T03:52:06+00:00)

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