KBOS / Sat Oct 17 / OFFICIAL STATION RECORD

Boston, MAHigh ≤ 52°F

FINAL OUTCOMENOOct 17 · 06:58 UTC

THE FORECAST FIELD

Who takes which side?

0% · NO50%YES · 100%

<1%

<1%

<1%

<1%

Consensus

Probabilities derived from each source’s mean and spread. Forecasts may have different initialization times.

HOW A MODEL CONTRACT WORKS

Head-to-head preview

ILLUSTRATIVE · NOT EXECUTED

The models are within 4 percentage points. Under the proposed policy, no contract would match.

These are current forecast comparisons, not locked entries. No credits have been committed. Read the proposed policy →

FOLLOW THE RUNS

Probability history

Recorded Reconstructed

Reconstructed from archived summary forecasts using a shared lead-dependent Gaussian error model. Times are initializations, not verified release times.

AIFS SingleICONGFSUKMETGEMIFS archive

Inspect a forecast 2026-10-17T18:00:00+00:00 · UTC

View the forecast data

UTC	AIFS	ICON	GFS	UKMET	GEM	IFS*
2026-10-02T06:00:00+00:00	35.9%	—	—	—	—	—
2026-10-02T12:00:00+00:00	58.5%	—	—	—	—	—
2026-10-02T18:00:00+00:00	19.3%	—	27.0%	—	—	—
2026-10-03T00:00:00+00:00	9.1%	—	—	—	—	10.5%
2026-10-03T06:00:00+00:00	13.1%	—	—	—	—	—
2026-10-03T12:00:00+00:00	12.6%	—	—	—	—	16.5%
2026-10-03T18:00:00+00:00	1.8%	—	—	—	—	—
2026-10-04T00:00:00+00:00	45.8%	—	—	—	—	8.7%
2026-10-04T06:00:00+00:00	30.1%	—	—	—	—	—
2026-10-04T12:00:00+00:00	5.9%	—	—	—	—	12.0%
2026-10-04T18:00:00+00:00	20.1%	—	—	—	—	—
2026-10-05T00:00:00+00:00	6.4%	—	—	—	—	4.5%
2026-10-05T06:00:00+00:00	11.8%	—	—	—	—	—
2026-10-05T12:00:00+00:00	14.9%	—	—	—	—	8.3%
2026-10-05T18:00:00+00:00	0.4%	—	—	—	—	—
2026-10-06T00:00:00+00:00	42.6%	—	—	—	—	7.1%
2026-10-06T06:00:00+00:00	40.0%	—	—	—	—	—
2026-10-06T12:00:00+00:00	25.6%	—	—	—	—	13.6%
2026-10-06T18:00:00+00:00	33.2%	—	—	—	—	—
2026-10-07T00:00:00+00:00	52.8%	—	—	—	—	16.7%
2026-10-07T06:00:00+00:00	33.2%	—	—	—	—	—
2026-10-07T12:00:00+00:00	8.8%	—	—	—	—	13.0%
2026-10-07T18:00:00+00:00	42.0%	—	—	—	—	—
2026-10-08T00:00:00+00:00	20.1%	—	1.2%	—	—	7.5%
2026-10-08T06:00:00+00:00	24.1%	—	3.9%	—	—	—
2026-10-08T12:00:00+00:00	15.8%	—	0.7%	—	—	4.4%
2026-10-08T18:00:00+00:00	25.3%	—	—	—	—	—
2026-10-09T00:00:00+00:00	16.4%	—	3.5%	—	—	9.3%
2026-10-09T06:00:00+00:00	13.1%	—	1.6%	—	—	—
2026-10-09T12:00:00+00:00	3.9%	—	1.5%	—	—	14.4%
2026-10-09T18:00:00+00:00	14.0%	—	1.4%	—	—	—
2026-10-10T00:00:00+00:00	30.0%	5.6%	2.1%	—	—	18.9%
2026-10-10T06:00:00+00:00	19.4%	—	1.1%	—	—	—
2026-10-10T12:00:00+00:00	47.9%	0.4%	0.7%	65.7%	—	19.9%
2026-10-10T18:00:00+00:00	62.7%	—	0.7%	—	—	—
2026-10-11T00:00:00+00:00	33.0%	—	0.4%	47.1%	—	19.4%
2026-10-11T06:00:00+00:00	59.6%	—	1.1%	—	—	—
2026-10-11T12:00:00+00:00	85.4%	30.9%	19.5%	62.0%	—	18.9%
2026-10-11T18:00:00+00:00	89.5%	—	40.7%	—	—	—
2026-10-12T00:00:00+00:00	85.1%	37.5%	14.5%	2.2%	—	32.3%
2026-10-12T06:00:00+00:00	67.4%	29.0%	1.1%	—	—	—
2026-10-12T12:00:00+00:00	61.5%	44.2%	30.8%	28.6%	—	30.8%
2026-10-12T18:00:00+00:00	59.3%	14.7%	32.6%	—	—	—
2026-10-13T00:00:00+00:00	20.2%	0.1%	25.5%	5.9%	—	28.4%
2026-10-13T06:00:00+00:00	9.6%	8.8%	0.3%	—	—	—
2026-10-13T12:00:00+00:00	17.8%	0.0%	0.1%	1.3%	—	9.0%
2026-10-13T18:00:00+00:00	3.6%	0.0%	0.4%	—	—	0.5%
2026-10-14T00:00:00+00:00	5.6%	0.0%	0.2%	0.0%	—	0.1%
2026-10-14T06:00:00+00:00	2.7%	0.0%	0.1%	—	—	0.1%
2026-10-14T12:00:00+00:00	2.2%	0.0%	0.1%	0.2%	—	0.0%
2026-10-14T18:00:00+00:00	2.0%	0.0%	0.0%	—	—	0.0%
2026-10-15T00:00:00+00:00	3.3%	0.0%	0.0%	0.1%	0.0%	0.0%
2026-10-15T06:00:00+00:00	11.2%	0.0%	0.0%	0.0%	—	—
2026-10-15T12:00:00+00:00	7.6%	0.0%	0.0%	0.2%	—	0.0%
2026-10-15T18:00:00+00:00	4.3%	0.0%	0.0%	0.1%	—	0.1%
2026-10-16T00:00:00+00:00	8.5%	0.0%	0.0%	0.2%	0.0%	0.2%
2026-10-16T06:00:00+00:00	9.8%	0.0%	0.0%	0.2%	—	0.2%
2026-10-16T12:00:00+00:00	4.3%	0.0%	0.0%	0.1%	0.0%	0.1%
2026-10-16T18:00:00+00:00	3.2%	0.0%	0.0%	0.1%	—	0.1%
2026-10-17T00:00:00+00:00	1.8%	0.0%	0.0%	0.0%	0.0%	0.0%
2026-10-17T06:00:00+00:00	71.5%	1.1%	27.2%	0.5%	—	1.0%
2026-10-17T12:00:00+00:00	72.4%	76.2%	56.3%	90.4%	88.3%	83.9%
2026-10-17T18:00:00+00:00	100.0%	85.0%	63.0%	92.7%	—	88.5%

THE MODEL BOX SCORE

Forecasts & evidence

MODEL	YES	MEAN	SPREAD σ	INITIALIZATION UTC	BRIER ↓
NWS forecast	88%	50.0°F	2.1°F	2026-10-17 03:00	0.7797
National Blend	71%	51.0°F	2.7°F	2026-10-17 00:00	0.5055
AIFS Single	1%	61.5°F	4.0°F	2026-10-16 18:00	0.0001
IFS HRES	<1%	62.9°F	3.7°F	2026-10-16 12:00	0.0000
IFS Ensemble	<1%	68.5°F	3.6°F	2026-10-16 00:00	0.0000
ICON	<1%	66.8°F	3.5°F	2026-10-16 12:00	0.0000
WeatherNext 2	<1%	62.1°F	2.9°F	2026-10-16 18:00	0.0000

Spread is the standard deviation used in the probability approximation. It is not a measured confidence rating. Brier here scores the latest recorded snapshot, not a league deadline.

SETTLEMENT & PROVENANCE

High ≤ 52°F · KBOS

Daily temperature props settle on the ACIS official station record. Inclusive and strict thresholds retain their exact meanings. Provisional observations do not replace the settlement record.

WP-KBOS-20261017-TMAX-LE52
Opened Oct 13 · 08:02 UTC

Original listing: Boston stays cold-for-here: high ≤ 52°F · Sat Oct 17

Original prop, full history & receipt ↗