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

Boston Logan · ECMWF IFS HRES · lead day 9

KBOS · ifs_hres · lead 9

Target day = initialization date + 9 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
tmax00Zbilinear30d15 1 QC4.33 [3.16, 5.31]4.25+1.41 [-1.99, 3.07]5.63 [3.58, 6.87]7% [0%, 21%]27%53%+0.53+0.522026-08-10 → 2026-08-30
tmax00Zbilinear90d15 1 QC4.33 [2.71, 5.39]4.25+1.41 [-2.64, 3.06]5.63 [2.80, 6.93]7% [0%, 23%]27%53%+0.53+0.522026-08-10 → 2026-08-30
tmax00Zbilinear365d15 1 QC4.33 [2.93, 5.37]4.25+1.41 [-2.64, 3.23]5.63 [3.07, 6.98]7% [0%, 25%]27%53%+0.53+0.522026-08-10 → 2026-08-30
tmax00Zbilinearall15 1 QC4.33 [2.97, 5.37]4.25+1.41 [-2.64, 3.34]5.63 [3.13, 6.80]7% [0%, 25%]27%53%+0.53+0.522026-08-10 → 2026-08-30
tmax00Znearest30d15 1 QC4.21 [3.01, 5.20]4.23+1.96 [-1.28, 3.58]5.58 [3.58, 6.79]13% [0%, 31%]40%53%+0.54+0.522026-08-10 → 2026-08-30
tmax00Znearest90d15 1 QC4.21 [2.76, 5.26]4.23+1.96 [-2.76, 3.55]5.58 [2.93, 6.78]13% [0%, 31%]40%53%+0.54+0.522026-08-10 → 2026-08-30
tmax00Znearest365d15 1 QC4.21 [2.96, 5.18]4.23+1.96 [-2.76, 3.65]5.58 [3.34, 6.82]13% [0%, 33%]40%53%+0.54+0.522026-08-10 → 2026-08-30
tmax00Znearestall15 1 QC4.21 [2.97, 5.27]4.23+1.96 [-2.76, 3.79]5.58 [3.34, 6.70]13% [0%, 33%]40%53%+0.54+0.522026-08-10 → 2026-08-30
tmax12Zbilinear30d14 1 QC4.27 [2.89, 6.92]3.19-3.34 [-5.32, -2.34]5.67 [3.33, 8.89]21% [0%, 32%]29%36%+0.52+0.642026-08-10 → 2026-08-30
tmax12Zbilinear90d14 1 QC4.27 [2.83, 7.54]3.19-3.34 [-5.34, -2.40]5.67 [2.83, 9.27]21% [0%, 31%]29%36%+0.52+0.642026-08-10 → 2026-08-30
tmax12Zbilinear365d14 1 QC4.27 [2.83, 7.60]3.19-3.34 [-5.32, -2.38]5.67 [2.83, 9.38]21% [0%, 33%]29%36%+0.52+0.642026-08-10 → 2026-08-30
tmax12Zbilinearall14 1 QC4.27 [2.81, 7.96]3.19-3.34 [-5.54, -2.31]5.67 [2.83, 9.92]21% [0%, 33%]29%36%+0.52+0.642026-08-10 → 2026-08-30
tmax12Znearest30d14 1 QC4.24 [2.51, 6.80]3.74-2.91 [-4.90, -1.50]5.72 [3.27, 8.91]21% [0%, 67%]36%50%+0.52+0.582026-08-10 → 2026-08-30
tmax12Znearest90d14 1 QC4.24 [0.93, 7.38]3.74-2.91 [-5.09, -0.93]5.72 [0.93, 9.34]21% [0%, 100%]36%50%+0.52+0.582026-08-10 → 2026-08-30
tmax12Znearest365d14 1 QC4.24 [0.93, 7.62]3.74-2.91 [-5.09, -0.93]5.72 [0.93, 9.47]21% [0%, 100%]36%50%+0.52+0.582026-08-10 → 2026-08-30
tmax12Znearestall14 1 QC4.24 [0.93, 7.93]3.74-2.91 [-5.15, -0.93]5.72 [0.93, 9.95]21% [0%, 100%]36%50%+0.52+0.582026-08-10 → 2026-08-30
tmin00Zbilinear30d15 1 QC3.00 [1.56, 4.98]3.03+1.76 [0.48, 3.46]4.25 [2.16, 6.60]33% [8%, 60%]47%60%+0.28+0.172026-08-10 → 2026-08-30
tmin00Zbilinear90d15 1 QC3.00 [0.47, 5.09]3.03+1.76 [-0.02, 3.40]4.25 [0.55, 6.57]33% [0%, 83%]47%60%+0.28+0.172026-08-10 → 2026-08-30
tmin00Zbilinear365d15 1 QC3.00 [0.69, 5.35]3.03+1.76 [0.02, 3.62]4.25 [0.80, 6.86]33% [0%, 75%]47%60%+0.28+0.172026-08-10 → 2026-08-30
tmin00Zbilinearall15 1 QC3.00 [0.69, 5.42]3.03+1.76 [0.19, 3.70]4.25 [0.80, 6.97]33% [0%, 75%]47%60%+0.28+0.172026-08-10 → 2026-08-30
tmin00Znearest30d15 1 QC2.90 [1.46, 4.96]2.94+1.74 [0.53, 3.28]4.25 [2.06, 6.59]40% [17%, 60%]47%67%+0.31+0.192026-08-10 → 2026-08-30
tmin00Znearest90d15 1 QC2.90 [0.53, 5.05]2.94+1.74 [-0.03, 3.32]4.25 [0.60, 6.54]40% [14%, 83%]47%67%+0.31+0.192026-08-10 → 2026-08-30
tmin00Znearest365d15 1 QC2.90 [0.74, 5.46]2.94+1.74 [-0.01, 3.50]4.25 [0.83, 6.83]40% [9%, 75%]47%67%+0.31+0.192026-08-10 → 2026-08-30
tmin00Znearestall15 1 QC2.90 [0.74, 5.47]2.94+1.74 [0.16, 3.50]4.25 [0.83, 6.94]40% [0%, 75%]47%67%+0.31+0.192026-08-10 → 2026-08-30
tmin12Zbilinear30d14 1 QC2.76 [1.53, 3.65]2.76+0.61 [-0.87, 1.55]3.29 [2.39, 3.97]29% [11%, 62%]36%43%+0.34+0.282026-08-10 → 2026-08-30
tmin12Zbilinear90d14 1 QC2.76 [0.77, 3.76]2.76+0.61 [-0.82, 1.65]3.29 [1.36, 4.11]29% [7%, 87%]36%43%+0.34+0.282026-08-10 → 2026-08-30
tmin12Zbilinear365d14 1 QC2.76 [1.15, 3.79]2.76+0.61 [-0.95, 1.65]3.29 [2.07, 4.07]29% [0%, 77%]36%43%+0.34+0.282026-08-10 → 2026-08-30
tmin12Zbilinearall14 1 QC2.76 [1.16, 3.96]2.76+0.61 [-0.86, 1.67]3.29 [2.06, 4.21]29% [0%, 75%]36%43%+0.34+0.282026-08-10 → 2026-08-30
tmin12Znearest30d14 1 QC2.86 [1.86, 3.51]2.81+0.72 [-0.75, 1.76]3.31 [2.62, 3.79]29% [11%, 62%]36%43%+0.32+0.272026-08-10 → 2026-08-30
tmin12Znearest90d14 1 QC2.86 [1.17, 3.56]2.81+0.72 [-0.68, 1.90]3.31 [1.65, 3.90]29% [7%, 87%]36%43%+0.32+0.272026-08-10 → 2026-08-30
tmin12Znearest365d14 1 QC2.86 [1.56, 3.64]2.81+0.72 [-0.97, 1.87]3.31 [2.40, 3.81]29% [0%, 77%]36%43%+0.32+0.272026-08-10 → 2026-08-30
tmin12Znearestall14 1 QC2.86 [1.56, 3.72]2.81+0.72 [-0.93, 1.89]3.31 [2.35, 3.94]29% [0%, 75%]36%43%+0.32+0.272026-08-10 → 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 KBOS, lead day 9, 00Z bilinear tmax+20+100-10-202026-08-10: -2.64 °F2026-08-16: +8.74 °F2026-08-17: +0.11 °F2026-08-18: +1.17 °F2026-08-19: -5.8 °F2026-08-20: -1.58 °F2026-08-21: +14.94 °F2026-08-22: +5.06 °F2026-08-23: +4.64 °F2026-08-24: +2.53 °F2026-08-25: -2.31 °F2026-08-26: +1.62 °F2026-08-27: -2.82 °F2026-08-29: +4.21 °F2026-08-30: -6.71 °F2026-08-102026-08-30°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 (21 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-6.71
2026-08-29+4.21
2026-08-28—
2026-08-27-2.82
2026-08-26+1.62
2026-08-25-2.31
2026-08-24+2.53
2026-08-23+4.64
2026-08-22+5.06
2026-08-21+14.94
2026-08-20-1.58
2026-08-19-5.80
2026-08-18+1.17
2026-08-17+0.11
2026-08-16+8.74
2026-08-15—
2026-08-14—
2026-08-13—
2026-08-12—
2026-08-11—
2026-08-10-2.64

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KBOS, lead day 9-20 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: 0 days-10 to -8 °F: 0 days-8 to -6 °F: 1 day-6 to -4 °F: 1 day-4 to -2 °F: 3 days-2 to 0 °F: 1 day0 to 2 °F: 3 days2 to 4 °F: 1 day4 to 6 °F: 3 days6 to 8 °F: 0 days8 to 10 °F: 1 day10 to 12 °F: 0 days12 to 14 °F: 0 days14 to 16 °F: 1 day16 to 18 °F: 0 days18 to 20 °F: 0 daysdashed: P50 |e| 2.82 · P90 |e| 7.93 °F-200+20 °Fn = 15 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
-12.00-10.000
-10.00-8.000
-8.00-6.001
-6.00-4.001
-4.00-2.003
-2.00+0.001
+0.00+2.003
+2.00+4.001
+4.00+6.003
+6.00+8.000
+8.00+10.001
+10.00+12.000
+12.00+14.000
+14.00+16.001
+16.00+18.000
+18.00+20.000

Month by month

00Z bilinear daily maximum, newest first.

Monthn MAE °FBias °F
2026-08154.33 +1.41

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-10 → 2026-08-30 15
ECMWF IFS HRES2026-08-10 → 2026-08-30 15
ECMWF IFS HRES2026-08-10 → 2026-08-30 14
ECMWF IFS HRES2026-08-10 → 2026-08-30 14

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 15 -1.48 [-2.28, 1.13] no
NCEP GFS 15 -2.65 [-6.10, -0.60] yes
GraphCast (IFS init) 15 -1.08 [-2.59, 0.90] no
Persistence (baseline) 15 -4.81 [-7.48, 1.48] no

Cite this page

ShortCastCheck, KBOS ifs_hres lead 9, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KBOS/model/ifs_hres/lead/9/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KBOS (Boston Logan), model ifs_hres, lead day 9. Methodology version 0.2, schema version 0.1, data through 2026-08-30. Accessed 2026-08-31. https://castcheck.zifanzhang.com/station/KBOS/model/ifs_hres/lead/9/

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