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

Boston Logan · ECMWF IFS HRES · lead day 8

KBOS · ifs_hres · lead 8

Target day = initialization date + 8 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
tmax00Zbilinear30d16 1 QC6.53 [4.65, 9.43]6.56-1.45 [-5.68, 1.21]7.73 [5.71, 9.97]0% [0%, 0%]19%31%+0.15+0.152026-08-09 → 2026-08-30
tmax00Zbilinear90d16 1 QC6.53 [4.64, 9.62]6.56-1.45 [-6.95, 1.24]7.73 [5.56, 10.27]0% [0%, 0%]19%31%+0.15+0.152026-08-09 → 2026-08-30
tmax00Zbilinear365d16 1 QC6.53 [4.46, 9.63]6.56-1.45 [-8.47, 1.61]7.73 [5.34, 10.27]0% [0%, 0%]19%31%+0.15+0.152026-08-09 → 2026-08-30
tmax00Zbilinearall16 1 QC6.53 [4.43, 9.80]6.56-1.45 [-7.88, 1.51]7.73 [5.35, 10.27]0% [0%, 0%]19%31%+0.15+0.152026-08-09 → 2026-08-30
tmax00Znearest30d16 1 QC6.53 [4.48, 9.75]6.53-0.64 [-4.95, 2.30]7.78 [5.39, 10.43]6% [0%, 15%]6%19%+0.15+0.152026-08-09 → 2026-08-30
tmax00Znearest90d16 1 QC6.53 [4.38, 10.09]6.53-0.64 [-6.39, 2.47]7.78 [5.21, 10.68]6% [0%, 15%]6%19%+0.15+0.152026-08-09 → 2026-08-30
tmax00Znearest365d16 1 QC6.53 [4.23, 10.15]6.53-0.64 [-7.34, 2.89]7.78 [4.93, 10.76]6% [0%, 16%]6%19%+0.15+0.152026-08-09 → 2026-08-30
tmax00Znearestall16 1 QC6.53 [4.20, 10.10]6.53-0.64 [-7.34, 2.70]7.78 [5.00, 10.71]6% [0%, 15%]6%19%+0.15+0.152026-08-09 → 2026-08-30
tmax12Zbilinear30d16 1 QC3.75 [3.04, 5.05]3.67-1.68 [-3.27, -0.84]4.64 [3.71, 5.81]12% [0%, 24%]31%50%+0.51+0.522026-08-09 → 2026-08-30
tmax12Zbilinear90d16 1 QC3.75 [3.02, 5.62]3.67-1.68 [-4.05, -0.83]4.64 [3.70, 5.86]12% [0%, 25%]31%50%+0.51+0.522026-08-09 → 2026-08-30
tmax12Zbilinear365d16 1 QC3.75 [2.91, 5.71]3.67-1.68 [-5.38, -0.71]4.64 [3.62, 5.86]12% [0%, 25%]31%50%+0.51+0.522026-08-09 → 2026-08-30
tmax12Zbilinearall16 1 QC3.75 [2.95, 5.71]3.67-1.68 [-4.68, -0.72]4.64 [3.62, 5.91]12% [0%, 25%]31%50%+0.51+0.522026-08-09 → 2026-08-30
tmax12Znearest30d16 1 QC3.75 [2.93, 5.12]3.76-1.25 [-3.00, -0.39]4.58 [3.56, 5.90]19% [0%, 33%]31%38%+0.51+0.512026-08-09 → 2026-08-30
tmax12Znearest90d16 1 QC3.75 [2.96, 5.40]3.76-1.25 [-3.84, -0.40]4.58 [3.57, 6.00]19% [0%, 33%]31%38%+0.51+0.512026-08-09 → 2026-08-30
tmax12Znearest365d16 1 QC3.75 [2.83, 5.40]3.76-1.25 [-5.13, -0.27]4.58 [3.51, 5.99]19% [0%, 36%]31%38%+0.51+0.512026-08-09 → 2026-08-30
tmax12Znearestall16 1 QC3.75 [2.87, 5.40]3.76-1.25 [-4.40, -0.33]4.58 [3.50, 6.04]19% [0%, 33%]31%38%+0.51+0.512026-08-09 → 2026-08-30
tmin00Zbilinear30d16 1 QC1.71 [1.18, 2.41]1.63+0.71 [-0.38, 1.21]2.13 [1.58, 2.63]38% [0%, 60%]69%81%+0.61+0.532026-08-09 → 2026-08-30
tmin00Zbilinear90d16 1 QC1.71 [1.17, 2.53]1.63+0.71 [-1.03, 1.26]2.13 [1.53, 2.69]38% [0%, 62%]69%81%+0.61+0.532026-08-09 → 2026-08-30
tmin00Zbilinear365d16 1 QC1.71 [1.14, 2.57]1.63+0.71 [-1.53, 1.22]2.13 [1.53, 2.71]38% [0%, 63%]69%81%+0.61+0.532026-08-09 → 2026-08-30
tmin00Zbilinearall16 1 QC1.71 [1.15, 2.69]1.63+0.71 [-1.26, 1.27]2.13 [1.49, 2.85]38% [0%, 62%]69%81%+0.61+0.532026-08-09 → 2026-08-30
tmin00Znearest30d16 1 QC1.74 [1.29, 2.31]1.54+0.92 [-0.12, 1.43]2.18 [1.71, 2.58]44% [10%, 65%]62%81%+0.60+0.562026-08-09 → 2026-08-30
tmin00Znearest90d16 1 QC1.74 [1.26, 2.43]1.54+0.92 [-0.66, 1.45]2.18 [1.54, 2.63]44% [0%, 67%]62%81%+0.60+0.562026-08-09 → 2026-08-30
tmin00Znearest365d16 1 QC1.74 [1.25, 2.41]1.54+0.92 [-1.26, 1.50]2.18 [1.51, 2.62]44% [0%, 70%]62%81%+0.60+0.562026-08-09 → 2026-08-30
tmin00Znearestall16 1 QC1.74 [1.26, 2.51]1.54+0.92 [-0.93, 1.50]2.18 [1.51, 2.70]44% [0%, 67%]62%81%+0.60+0.562026-08-09 → 2026-08-30
tmin12Zbilinear30d16 1 QC1.74 [1.00, 2.22]1.66+0.98 [0.16, 1.82]2.17 [1.36, 2.61]31% [19%, 67%]56%75%+0.60+0.522026-08-09 → 2026-08-30
tmin12Zbilinear90d16 1 QC1.74 [0.31, 2.25]1.66+0.98 [0.12, 1.93]2.17 [0.37, 2.63]31% [19%, 100%]56%75%+0.60+0.522026-08-09 → 2026-08-30
tmin12Zbilinear365d16 1 QC1.74 [0.31, 2.30]1.66+0.98 [0.12, 1.95]2.17 [0.37, 2.65]31% [17%, 100%]56%75%+0.60+0.522026-08-09 → 2026-08-30
tmin12Zbilinearall16 1 QC1.74 [0.31, 2.28]1.66+0.98 [0.12, 1.90]2.17 [0.41, 2.64]31% [17%, 100%]56%75%+0.60+0.522026-08-09 → 2026-08-30
tmin12Znearest30d16 1 QC1.83 [1.22, 2.33]1.63+1.22 [0.41, 2.08]2.27 [1.63, 2.73]38% [24%, 67%]56%69%+0.58+0.542026-08-09 → 2026-08-30
tmin12Znearest90d16 1 QC1.83 [0.56, 2.36]1.63+1.22 [0.41, 2.21]2.27 [0.61, 2.75]38% [24%, 100%]56%69%+0.58+0.542026-08-09 → 2026-08-30
tmin12Znearest365d16 1 QC1.83 [0.43, 2.37]1.63+1.22 [0.36, 2.21]2.27 [0.43, 2.77]38% [22%, 100%]56%69%+0.58+0.542026-08-09 → 2026-08-30
tmin12Znearestall16 1 QC1.83 [0.57, 2.35]1.63+1.22 [0.33, 2.19]2.27 [0.62, 2.75]38% [24%, 100%]56%69%+0.58+0.542026-08-09 → 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 8, 00Z bilinear tmax+20+100-10-202026-08-09: -8.47 °F2026-08-15: +9.58 °F2026-08-16: -9.2 °F2026-08-17: +14.39 °F2026-08-18: +1.89 °F2026-08-19: -7.19 °F2026-08-20: -11 °F2026-08-21: +2.8 °F2026-08-22: +2.42 °F2026-08-23: +4.46 °F2026-08-24: -6.49 °F2026-08-25: -1.27 °F2026-08-26: +1.32 °F2026-08-27: -6.57 °F2026-08-29: +3.84 °F2026-08-30: -13.65 °F2026-08-092026-08-30°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 (22 days, newest first) · download CSV
Climatological dayError °F
2026-08-30-13.65
2026-08-29+3.84
2026-08-28—
2026-08-27-6.57
2026-08-26+1.32
2026-08-25-1.27
2026-08-24-6.49
2026-08-23+4.46
2026-08-22+2.42
2026-08-21+2.80
2026-08-20-11.00
2026-08-19-7.19
2026-08-18+1.89
2026-08-17+14.39
2026-08-16-9.20
2026-08-15+9.58
2026-08-14—
2026-08-13—
2026-08-12—
2026-08-11—
2026-08-10—
2026-08-09-8.47

Error distribution

Distribution of the signed daily error in °F for ECMWF IFS HRES at KBOS, lead day 8-20 to -18 °F: 0 days-18 to -16 °F: 0 days-16 to -14 °F: 0 days-14 to -12 °F: 1 day-12 to -10 °F: 1 day-10 to -8 °F: 2 days-8 to -6 °F: 3 days-6 to -4 °F: 0 days-4 to -2 °F: 0 days-2 to 0 °F: 1 day0 to 2 °F: 2 days2 to 4 °F: 3 days4 to 6 °F: 1 day6 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| 6.53 · P90 |e| 12.33 °F-200+20 °Fn = 16 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
-14.00-12.001
-12.00-10.001
-10.00-8.002
-8.00-6.003
-6.00-4.000
-4.00-2.000
-2.00+0.001
+0.00+2.002
+2.00+4.003
+4.00+6.001
+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
2026-08166.53 -1.45

Availability

ModelScored period DaysCoverage
ECMWF IFS HRES2026-08-09 → 2026-08-30 16
ECMWF IFS HRES2026-08-09 → 2026-08-30 16
ECMWF IFS HRES2026-08-09 → 2026-08-30 16
ECMWF IFS HRES2026-08-09 → 2026-08-30 16

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 16 +1.17 [-1.81, 5.91] no
NCEP GFS 16 -0.11 [-3.18, 5.05] no
GraphCast (IFS init) 16 +0.46 [-2.57, 7.02] no
Persistence (baseline) 16 -1.15 [-2.73, 1.79] no

Cite this page

ShortCastCheck, KBOS ifs_hres lead 8, methodology v0.2, accessed 2026-08-31, https://castcheck.zifanzhang.com/station/KBOS/model/ifs_hres/lead/8/

LongCastCheck (2026). Station-level verification of raw weather-model 2 m temperature forecasts: KBOS (Boston Logan), model ifs_hres, lead day 8. 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/8/

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