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

Washington Reagan · ECMWF AIFS Single · lead day 7

KDCA · aifs_single · 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, aifs-single-gpid5, 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
tmax00Zbilinear30d23 1 QC3.26 [2.12, 4.81]2.06-3.06 [-4.80, -1.67]3.97 [2.54, 5.39]17% [0%, 37%]39%57%+0.28+0.552026-08-08 → 2026-08-30
tmax00Zbilinear90d23 1 QC3.26 [2.03, 5.07]2.06-3.06 [-5.07, -1.49]3.97 [2.33, 5.51]17% [0%, 38%]39%57%+0.28+0.552026-08-08 → 2026-08-30
tmax00Zbilinear365d23 1 QC3.26 [2.01, 5.38]2.06-3.06 [-5.38, -1.52]3.97 [2.36, 5.72]17% [0%, 39%]39%57%+0.28+0.552026-08-08 → 2026-08-30
tmax00Zbilinearall23 1 QC3.26 [1.97, 5.25]2.06-3.06 [-5.25, -1.48]3.97 [2.31, 5.64]17% [0%, 38%]39%57%+0.28+0.552026-08-08 → 2026-08-30
tmax00Znearest30d23 1 QC3.02 [1.88, 4.59]2.07-2.80 [-4.54, -1.38]3.77 [2.33, 5.20]22% [0%, 38%]43%61%+0.33+0.542026-08-08 → 2026-08-30
tmax00Znearest90d23 1 QC3.02 [1.80, 4.85]2.07-2.80 [-4.85, -1.20]3.77 [2.12, 5.37]22% [0%, 39%]43%61%+0.33+0.542026-08-08 → 2026-08-30
tmax00Znearest365d23 1 QC3.02 [1.77, 5.15]2.07-2.80 [-5.15, -1.23]3.77 [2.14, 5.56]22% [0%, 41%]43%61%+0.33+0.542026-08-08 → 2026-08-30
tmax00Znearestall23 1 QC3.02 [1.76, 5.05]2.07-2.80 [-5.05, -1.19]3.77 [2.08, 5.45]22% [0%, 43%]43%61%+0.33+0.542026-08-08 → 2026-08-30
tmax12Zbilinear30d23 1 QC3.51 [2.22, 5.01]2.44-2.81 [-4.71, -1.41]4.16 [2.76, 5.44]17% [0%, 32%]35%39%+0.22+0.462026-08-08 → 2026-08-30
tmax12Zbilinear90d23 1 QC3.51 [1.93, 5.47]2.44-2.81 [-5.47, -1.13]4.16 [2.29, 5.80]17% [0%, 33%]35%39%+0.22+0.462026-08-08 → 2026-08-30
tmax12Zbilinear365d23 1 QC3.51 [1.81, 5.54]2.44-2.81 [-5.54, -1.11]4.16 [2.16, 5.88]17% [0%, 33%]35%39%+0.22+0.462026-08-08 → 2026-08-30
tmax12Zbilinearall23 1 QC3.51 [1.86, 5.71]2.44-2.81 [-5.71, -1.11]4.16 [2.25, 5.98]17% [0%, 36%]35%39%+0.22+0.462026-08-08 → 2026-08-30
tmax12Znearest30d23 1 QC3.32 [2.09, 4.83]2.46-2.51 [-4.48, -1.07]4.00 [2.61, 5.28]13% [0%, 25%]35%48%+0.27+0.462026-08-08 → 2026-08-30
tmax12Znearest90d23 1 QC3.32 [1.82, 5.32]2.46-2.51 [-5.32, -0.81]4.00 [2.16, 5.66]13% [0%, 26%]35%48%+0.27+0.462026-08-08 → 2026-08-30
tmax12Znearest365d23 1 QC3.32 [1.69, 5.36]2.46-2.51 [-5.36, -0.81]4.00 [2.04, 5.75]13% [0%, 27%]35%48%+0.27+0.462026-08-08 → 2026-08-30
tmax12Znearestall23 1 QC3.32 [1.72, 5.56]2.46-2.51 [-5.56, -0.80]4.00 [2.10, 5.87]13% [0%, 29%]35%48%+0.27+0.462026-08-08 → 2026-08-30
tmin00Zbilinear30d23 1 QC2.54 [2.05, 2.93]2.47+0.58 [-1.26, 2.11]3.03 [2.43, 3.44]22% [8%, 35%]48%61%+0.46+0.482026-08-08 → 2026-08-30
tmin00Zbilinear90d23 1 QC2.54 [2.03, 2.94]2.47+0.58 [-1.92, 2.31]3.03 [2.40, 3.46]22% [5%, 36%]48%61%+0.46+0.482026-08-08 → 2026-08-30
tmin00Zbilinear365d23 1 QC2.54 [1.94, 2.95]2.47+0.58 [-1.99, 2.45]3.03 [2.32, 3.49]22% [0%, 36%]48%61%+0.46+0.482026-08-08 → 2026-08-30
tmin00Zbilinearall23 1 QC2.54 [1.83, 2.97]2.47+0.58 [-2.08, 2.30]3.03 [2.07, 3.49]22% [0%, 36%]48%61%+0.46+0.482026-08-08 → 2026-08-30
tmin00Znearest30d23 1 QC2.57 [2.04, 3.03]2.46+0.88 [-0.94, 2.44]3.11 [2.35, 3.62]26% [9%, 40%]48%65%+0.46+0.482026-08-08 → 2026-08-30
tmin00Znearest90d23 1 QC2.57 [1.92, 3.07]2.46+0.88 [-1.60, 2.62]3.11 [2.24, 3.66]26% [6%, 41%]48%65%+0.46+0.482026-08-08 → 2026-08-30
tmin00Znearest365d23 1 QC2.57 [1.84, 3.10]2.46+0.88 [-1.68, 2.76]3.11 [2.17, 3.69]26% [0%, 43%]48%65%+0.46+0.482026-08-08 → 2026-08-30
tmin00Znearestall23 1 QC2.57 [1.83, 3.09]2.46+0.88 [-1.81, 2.61]3.11 [1.98, 3.71]26% [0%, 43%]48%65%+0.46+0.482026-08-08 → 2026-08-30
tmin12Zbilinear30d23 1 QC2.73 [2.21, 3.28]2.79+0.27 [-1.66, 1.98]3.37 [2.77, 3.83]22% [0%, 43%]39%57%+0.42+0.412026-08-08 → 2026-08-30
tmin12Zbilinear90d23 1 QC2.73 [2.19, 3.27]2.79+0.27 [-2.15, 2.23]3.37 [2.65, 3.84]22% [0%, 43%]39%57%+0.42+0.412026-08-08 → 2026-08-30
tmin12Zbilinear365d23 1 QC2.73 [2.16, 3.24]2.79+0.27 [-2.22, 2.45]3.37 [2.59, 3.82]22% [0%, 45%]39%57%+0.42+0.412026-08-08 → 2026-08-30
tmin12Zbilinearall23 1 QC2.73 [2.12, 3.29]2.79+0.27 [-2.33, 2.44]3.37 [2.63, 3.86]22% [0%, 43%]39%57%+0.42+0.412026-08-08 → 2026-08-30
tmin12Znearest30d23 1 QC2.72 [2.14, 3.30]2.78+0.60 [-1.34, 2.33]3.41 [2.65, 3.95]30% [12%, 48%]43%61%+0.43+0.412026-08-08 → 2026-08-30
tmin12Znearest90d23 1 QC2.72 [2.05, 3.34]2.78+0.60 [-1.80, 2.56]3.41 [2.48, 4.00]30% [8%, 47%]43%61%+0.43+0.412026-08-08 → 2026-08-30
tmin12Znearest365d23 1 QC2.72 [2.01, 3.30]2.78+0.60 [-1.88, 2.82]3.41 [2.39, 3.99]30% [8%, 50%]43%61%+0.43+0.412026-08-08 → 2026-08-30
tmin12Znearestall23 1 QC2.72 [2.03, 3.37]2.78+0.60 [-1.99, 2.82]3.41 [2.46, 4.02]30% [8%, 47%]43%61%+0.43+0.412026-08-08 → 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 AIFS Single at KDCA, lead day 7, 00Z bilinear tmax+10+50-5-102026-08-08: -1.95 °F2026-08-09: -2.91 °F2026-08-10: +1.29 °F2026-08-11: -1.15 °F2026-08-12: -2.69 °F2026-08-13: -1.01 °F2026-08-14: +0.96 °F2026-08-15: -5.39 °F2026-08-16: -0.55 °F2026-08-17: -4.39 °F2026-08-18: -0.82 °F2026-08-19: -3.79 °F2026-08-20: -0.88 °F2026-08-21: -2.34 °F2026-08-22: -1.67 °F2026-08-23: -3.38 °F2026-08-24: -6.86 °F2026-08-25: -5.34 °F2026-08-26: -2.39 °F2026-08-27: -9.47 °F2026-08-28: -5.83 °F2026-08-29: -4.76 °F2026-08-30: -5.13 °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
2026-08-30-5.13
2026-08-29-4.76
2026-08-28-5.83
2026-08-27-9.47
2026-08-26-2.39
2026-08-25-5.34
2026-08-24-6.86
2026-08-23-3.38
2026-08-22-1.67
2026-08-21-2.34
2026-08-20-0.88
2026-08-19-3.79
2026-08-18-0.82
2026-08-17-4.39
2026-08-16-0.55
2026-08-15-5.39
2026-08-14+0.96
2026-08-13-1.01
2026-08-12-2.69
2026-08-11-1.15
2026-08-10+1.29
2026-08-09-2.91
2026-08-08-1.95

Error distribution

Distribution of the signed daily error in °F for ECMWF AIFS Single at KDCA, lead day 7-10 to -9 °F: 1 day-9 to -8 °F: 0 days-8 to -7 °F: 0 days-7 to -6 °F: 1 day-6 to -5 °F: 4 days-5 to -4 °F: 2 days-4 to -3 °F: 2 days-3 to -2 °F: 4 days-2 to -1 °F: 4 days-1 to 0 °F: 3 days0 to 1 °F: 1 day1 to 2 °F: 1 day2 to 3 °F: 0 days3 to 4 °F: 0 days4 to 5 °F: 0 days5 to 6 °F: 0 days6 to 7 °F: 0 days7 to 8 °F: 0 days8 to 9 °F: 0 days9 to 10 °F: 0 daysdashed: P50 |e| 2.69 · P90 |e| 5.74 °F-100+10 °Fn = 23 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
-10.00-9.001
-9.00-8.000
-8.00-7.000
-7.00-6.001
-6.00-5.004
-5.00-4.002
-4.00-3.002
-3.00-2.004
-2.00-1.004
-1.00+0.003
+0.00+1.001
+1.00+2.001
+2.00+3.000
+3.00+4.000
+4.00+5.000
+5.00+6.000
+6.00+7.000
+7.00+8.000
+8.00+9.000
+9.00+10.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08233.26 -3.06

Availability

ModelScored period DaysCoverage
ECMWF AIFS Single2026-08-08 → 2026-08-30 23
ECMWF AIFS Single2026-08-08 → 2026-08-30 23
ECMWF AIFS Single2026-08-08 → 2026-08-30 23
ECMWF AIFS Single2026-08-08 → 2026-08-30 23

Compared with other models

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

Other modelCommon days MAE difference °FDistinguishable
NCEP GFS 23 -1.21 [-2.35, 0.87] no
GraphCast (IFS init) 23 -1.56 [-2.89, -0.47] yes
ECMWF IFS HRES 18 -0.20 [-2.90, 2.66] no
Persistence (baseline) 23 -1.26 [-2.34, 0.25] no

Cite this page

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

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KDCA (Washington Reagan), model aifs_single, 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/KDCA/model/aifs_single/lead/7/

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

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