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

Washington Reagan · ECMWF IFS HRES · lead day 2

KDCA · ifs_hres · lead 2

Target day = initialization date + 2 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
tmax00Zbilinear30d22 1 QC4.10 [3.09, 5.05]2.77-2.96 [-3.91, -1.85]4.74 [3.55, 5.63]9% [0%, 22%]27%27%-0.14+0.232026-08-03 → 2026-08-30
tmax00Zbilinear90d22 1 QC4.10 [2.94, 5.13]2.77-2.96 [-3.99, -1.69]4.74 [3.34, 5.66]9% [0%, 22%]27%27%-0.14+0.232026-08-03 → 2026-08-30
tmax00Zbilinear365d22 1 QC4.10 [2.82, 5.18]2.77-2.96 [-4.21, -1.76]4.74 [3.26, 5.75]9% [0%, 22%]27%27%-0.14+0.232026-08-03 → 2026-08-30
tmax00Zbilinearall22 1 QC4.10 [2.96, 5.20]2.77-2.96 [-4.21, -1.67]4.74 [3.36, 5.69]9% [0%, 22%]27%27%-0.14+0.232026-08-03 → 2026-08-30
tmax00Znearest30d22 1 QC3.90 [2.92, 4.76]2.81-2.36 [-3.44, -1.28]4.43 [3.46, 5.20]14% [0%, 30%]18%32%-0.09+0.222026-08-03 → 2026-08-30
tmax00Znearest90d22 1 QC3.90 [2.74, 4.92]2.81-2.36 [-3.58, -1.03]4.43 [3.16, 5.37]14% [0%, 33%]18%32%-0.09+0.222026-08-03 → 2026-08-30
tmax00Znearest365d22 1 QC3.90 [2.62, 4.92]2.81-2.36 [-3.64, -1.20]4.43 [3.05, 5.36]14% [0%, 33%]18%32%-0.09+0.222026-08-03 → 2026-08-30
tmax00Znearestall22 1 QC3.90 [2.76, 5.09]2.81-2.36 [-3.83, -1.09]4.43 [3.22, 5.49]14% [0%, 33%]18%32%-0.09+0.222026-08-03 → 2026-08-30
tmax12Zbilinear30d22 1 QC3.52 [2.49, 4.54]2.35-2.97 [-4.51, -0.87]4.13 [3.02, 4.94]18% [6%, 32%]27%36%-0.01+0.332026-08-03 → 2026-08-30
tmax12Zbilinear90d22 1 QC3.52 [2.43, 4.73]2.35-2.97 [-4.73, -0.61]4.13 [2.88, 5.05]18% [0%, 31%]27%36%-0.01+0.332026-08-03 → 2026-08-30
tmax12Zbilinear365d22 1 QC3.52 [2.35, 4.85]2.35-2.97 [-4.85, -0.54]4.13 [2.74, 5.16]18% [0%, 33%]27%36%-0.01+0.332026-08-03 → 2026-08-30
tmax12Zbilinearall22 1 QC3.52 [2.41, 4.86]2.35-2.97 [-4.86, -0.44]4.13 [2.84, 5.19]18% [0%, 31%]27%36%-0.01+0.332026-08-03 → 2026-08-30
tmax12Znearest30d22 1 QC3.18 [2.26, 4.12]2.39-2.47 [-4.00, -0.35]3.80 [2.90, 4.45]23% [7%, 38%]27%41%+0.09+0.322026-08-03 → 2026-08-30
tmax12Znearest90d22 1 QC3.18 [2.22, 4.27]2.39-2.47 [-4.23, 0.00]3.80 [2.83, 4.59]23% [0%, 38%]27%41%+0.09+0.322026-08-03 → 2026-08-30
tmax12Znearest365d22 1 QC3.18 [2.13, 4.38]2.39-2.47 [-4.38, 0.02]3.80 [2.70, 4.66]23% [0%, 38%]27%41%+0.09+0.322026-08-03 → 2026-08-30
tmax12Znearestall22 1 QC3.18 [2.22, 4.46]2.39-2.47 [-4.44, 0.17]3.80 [2.85, 4.68]23% [0%, 38%]27%41%+0.09+0.322026-08-03 → 2026-08-30
tmin00Zbilinear30d22 1 QC2.14 [1.56, 2.62]2.11-0.18 [-1.58, 1.05]2.71 [2.11, 3.10]32% [10%, 54%]59%68%+0.44+0.452026-08-03 → 2026-08-30
tmin00Zbilinear90d22 1 QC2.14 [1.50, 2.65]2.11-0.18 [-1.62, 1.14]2.71 [1.96, 3.11]32% [0%, 54%]59%68%+0.44+0.452026-08-03 → 2026-08-30
tmin00Zbilinear365d22 1 QC2.14 [1.49, 2.65]2.11-0.18 [-1.62, 1.23]2.71 [1.98, 3.11]32% [0%, 58%]59%68%+0.44+0.452026-08-03 → 2026-08-30
tmin00Zbilinearall22 1 QC2.14 [1.50, 2.64]2.11-0.18 [-1.66, 1.30]2.71 [1.92, 3.09]32% [0%, 56%]59%68%+0.44+0.452026-08-03 → 2026-08-30
tmin00Znearest30d22 1 QC2.23 [1.69, 2.69]2.22-0.04 [-1.54, 1.26]2.77 [2.16, 3.19]32% [10%, 54%]59%68%+0.42+0.422026-08-03 → 2026-08-30
tmin00Znearest90d22 1 QC2.23 [1.63, 2.72]2.22-0.04 [-1.72, 1.34]2.77 [1.99, 3.20]32% [0%, 54%]59%68%+0.42+0.422026-08-03 → 2026-08-30
tmin00Znearest365d22 1 QC2.23 [1.60, 2.71]2.22-0.04 [-1.70, 1.46]2.77 [2.04, 3.19]32% [0%, 58%]59%68%+0.42+0.422026-08-03 → 2026-08-30
tmin00Znearestall22 1 QC2.23 [1.63, 2.70]2.22-0.04 [-1.83, 1.52]2.77 [1.99, 3.17]32% [0%, 56%]59%68%+0.42+0.422026-08-03 → 2026-08-30
tmin12Zbilinear30d22 1 QC2.27 [1.38, 3.19]2.30+0.39 [-0.95, 1.81]3.04 [1.96, 3.82]41% [18%, 61%]59%64%+0.42+0.412026-08-03 → 2026-08-30
tmin12Zbilinear90d22 1 QC2.27 [1.24, 3.23]2.30+0.39 [-1.00, 2.11]3.04 [1.69, 3.89]41% [14%, 62%]59%64%+0.42+0.412026-08-03 → 2026-08-30
tmin12Zbilinear365d22 1 QC2.27 [1.24, 3.35]2.30+0.39 [-1.08, 2.07]3.04 [1.66, 3.93]41% [12%, 64%]59%64%+0.42+0.412026-08-03 → 2026-08-30
tmin12Zbilinearall22 1 QC2.27 [1.18, 3.34]2.30+0.39 [-1.17, 2.08]3.04 [1.54, 3.97]41% [13%, 67%]59%64%+0.42+0.412026-08-03 → 2026-08-30
tmin12Znearest30d22 1 QC2.19 [1.44, 2.93]2.22+0.60 [-0.69, 1.96]2.96 [2.02, 3.58]41% [29%, 56%]59%73%+0.44+0.432026-08-03 → 2026-08-30
tmin12Znearest90d22 1 QC2.19 [1.29, 2.98]2.22+0.60 [-0.76, 2.15]2.96 [1.75, 3.65]41% [25%, 60%]59%73%+0.44+0.432026-08-03 → 2026-08-30
tmin12Znearest365d22 1 QC2.19 [1.26, 2.98]2.22+0.60 [-0.78, 2.22]2.96 [1.67, 3.64]41% [25%, 60%]59%73%+0.44+0.432026-08-03 → 2026-08-30
tmin12Znearestall22 1 QC2.19 [1.28, 3.03]2.22+0.60 [-0.83, 2.12]2.96 [1.64, 3.65]41% [25%, 62%]59%73%+0.44+0.432026-08-03 → 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 2, 00Z bilinear tmax+20+100-10-202026-08-03: -5.58 °F2026-08-08: -3.39 °F2026-08-09: -0.76 °F2026-08-11: +3.98 °F2026-08-13: -3.8 °F2026-08-14: -8.15 °F2026-08-15: -1.95 °F2026-08-16: +6.81 °F2026-08-17: -6.61 °F2026-08-18: -4.56 °F2026-08-19: -3.85 °F2026-08-20: -10.14 °F2026-08-21: -1.95 °F2026-08-22: +1.31 °F2026-08-23: -5.49 °F2026-08-24: -4.39 °F2026-08-25: -4.66 °F2026-08-26: +0.45 °F2026-08-27: -3.45 °F2026-08-28: -4.84 °F2026-08-29: -1.06 °F2026-08-30: -3.06 °F2026-08-032026-08-30°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 (28 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-3.06
2026-08-29-1.06
2026-08-28-4.84
2026-08-27-3.45
2026-08-26+0.45
2026-08-25-4.66
2026-08-24-4.39
2026-08-23-5.49
2026-08-22+1.31
2026-08-21-1.95
2026-08-20-10.14
2026-08-19-3.85
2026-08-18-4.56
2026-08-17-6.61
2026-08-16+6.81
2026-08-15-1.95
2026-08-14-8.15
2026-08-13-3.80
2026-08-12—
2026-08-11+3.98
2026-08-10—
2026-08-09-0.76
2026-08-08-3.39
2026-08-07—
2026-08-06—
2026-08-05—
2026-08-04—
2026-08-03-5.58

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KDCA, lead day 2-20 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: 1 day-6 to -4 °F: 6 days-4 to -2 °F: 5 days-2 to 0 °F: 4 days0 to 2 °F: 2 days2 to 4 °F: 1 day4 to 6 °F: 0 days6 to 8 °F: 1 day8 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| 3.91 · P90 |e| 6.79 °F-200+20 °Fn = 22 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
-8.00-6.001
-6.00-4.006
-4.00-2.005
-2.00+0.004
+0.00+2.002
+2.00+4.001
+4.00+6.000
+6.00+8.001
+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
2026-08224.10 -2.96

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-03 → 2026-08-30 22
ECMWF IFS HRES2026-08-03 → 2026-08-30 22
ECMWF IFS HRES2026-08-03 → 2026-08-30 22
ECMWF IFS HRES2026-08-03 → 2026-08-30 22

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 22 +1.41 [0.44, 2.72] yes
Aurora (IFS init) 1 -4.70 [-4.70, -4.70] yes
FourCastNet v2 (IFS init) 1 +0.17 [0.17, 0.17] yes
NCEP GFS 22 +1.03 [-0.45, 1.90] no
GraphCast (IFS init) 20 -0.53 [-2.12, 1.04] no
Pangu-Weather (IFS init) 1 -0.64 [-0.64, -0.64] yes
Persistence (baseline) 22 +0.51 [-0.78, 2.27] no

Cite this page

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

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

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