KPHL / Sun Oct 18 / OFFICIAL STATION RECORD

Philadelphia, PAHigh ≤ 55°F

FINAL OUTCOMENOOct 18 · 04:13 UTC

THE FORECAST FIELD

Who takes which side?

0% · NO50%YES · 100%

25%

17%

<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

ICONYES 12.8¢Risks 12.75u

WN2NO 87.2¢Risks 87.25u

100 contracts at the midpoint of these model probabilities. Each contract pays 1u to the winning side.

ICON +87.25u · WN2 −87.25u

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 2026-10-18T18:00:00+00:00 · UTC

View the forecast data

UTC	AIFS	ICON	GFS	UKMET	GEM	IFS*
2026-10-03T06:00:00+00:00	92.9%	—	—	—	—	—
2026-10-03T12:00:00+00:00	78.8%	—	—	—	—	47.3%
2026-10-03T18:00:00+00:00	14.0%	—	—	—	—	—
2026-10-04T00:00:00+00:00	44.7%	—	—	—	—	7.7%
2026-10-04T06:00:00+00:00	3.8%	—	—	—	—	—
2026-10-04T12:00:00+00:00	2.1%	—	—	—	—	7.1%
2026-10-04T18:00:00+00:00	0.6%	—	—	—	—	—
2026-10-05T00:00:00+00:00	12.8%	—	—	—	—	5.3%
2026-10-05T06:00:00+00:00	9.8%	—	—	—	—	—
2026-10-05T12:00:00+00:00	41.5%	—	—	—	—	11.8%
2026-10-05T18:00:00+00:00	70.3%	—	—	—	—	—
2026-10-06T00:00:00+00:00	66.5%	—	—	—	—	9.3%
2026-10-06T06:00:00+00:00	66.0%	—	—	—	—	—
2026-10-06T12:00:00+00:00	22.4%	—	—	—	—	18.9%
2026-10-06T18:00:00+00:00	40.0%	—	—	—	—	—
2026-10-07T00:00:00+00:00	30.1%	—	—	—	—	21.2%
2026-10-07T06:00:00+00:00	22.0%	—	—	—	—	—
2026-10-07T12:00:00+00:00	2.8%	—	—	—	—	21.1%
2026-10-07T18:00:00+00:00	19.6%	—	—	—	—	—
2026-10-08T00:00:00+00:00	23.7%	—	—	—	—	20.8%
2026-10-08T06:00:00+00:00	36.8%	—	—	—	—	—
2026-10-08T12:00:00+00:00	12.4%	—	—	—	—	18.5%
2026-10-08T18:00:00+00:00	66.3%	—	—	—	—	—
2026-10-09T00:00:00+00:00	0.9%	—	—	—	—	20.5%
2026-10-09T06:00:00+00:00	47.6%	—	—	—	—	—
2026-10-09T12:00:00+00:00	72.4%	—	53.0%	—	—	19.7%
2026-10-09T18:00:00+00:00	82.3%	—	—	—	—	—
2026-10-10T00:00:00+00:00	72.0%	—	15.7%	—	—	31.8%
2026-10-10T06:00:00+00:00	84.0%	—	70.7%	—	—	—
2026-10-10T12:00:00+00:00	52.6%	—	46.8%	—	—	30.6%
2026-10-10T18:00:00+00:00	52.0%	—	83.3%	—	—	—
2026-10-11T00:00:00+00:00	77.7%	—	87.9%	—	—	45.3%
2026-10-11T06:00:00+00:00	58.2%	—	86.2%	—	—	—
2026-10-11T12:00:00+00:00	16.2%	17.1%	72.0%	60.4%	—	36.2%
2026-10-11T18:00:00+00:00	5.7%	—	55.0%	—	—	—
2026-10-12T00:00:00+00:00	12.4%	10.3%	56.6%	24.3%	—	29.7%
2026-10-12T06:00:00+00:00	27.4%	—	39.6%	—	—	—
2026-10-12T12:00:00+00:00	16.0%	33.7%	47.7%	16.9%	—	38.0%
2026-10-12T18:00:00+00:00	10.5%	—	57.0%	—	—	—
2026-10-13T00:00:00+00:00	26.1%	8.7%	29.5%	20.1%	—	33.0%
2026-10-13T06:00:00+00:00	32.6%	74.4%	16.3%	—	—	—
2026-10-13T12:00:00+00:00	33.8%	7.4%	9.3%	35.3%	—	33.8%
2026-10-13T18:00:00+00:00	46.6%	14.2%	5.4%	—	—	—
2026-10-14T00:00:00+00:00	46.5%	17.8%	6.8%	41.3%	—	60.4%
2026-10-14T06:00:00+00:00	35.9%	35.9%	10.3%	—	—	—
2026-10-14T12:00:00+00:00	19.6%	33.0%	11.5%	50.0%	—	59.1%
2026-10-14T18:00:00+00:00	16.5%	29.2%	14.3%	—	—	62.1%
2026-10-15T00:00:00+00:00	19.7%	20.3%	13.6%	50.0%	—	51.9%
2026-10-15T06:00:00+00:00	11.0%	30.8%	13.0%	—	—	—
2026-10-15T12:00:00+00:00	12.8%	14.5%	13.4%	49.0%	—	42.8%
2026-10-15T18:00:00+00:00	15.0%	16.9%	15.6%	—	—	—
2026-10-16T00:00:00+00:00	14.9%	13.1%	29.2%	43.5%	—	63.9%
2026-10-16T06:00:00+00:00	9.2%	14.8%	34.6%	98.6%	—	45.5%
2026-10-16T12:00:00+00:00	11.6%	18.3%	19.1%	35.2%	—	36.3%
2026-10-16T18:00:00+00:00	7.4%	14.5%	15.2%	32.5%	—	31.4%
2026-10-17T00:00:00+00:00	6.7%	11.2%	11.8%	28.7%	56.2%	30.9%
2026-10-17T06:00:00+00:00	5.6%	12.8%	10.3%	20.0%	—	24.8%
2026-10-17T12:00:00+00:00	7.4%	10.7%	5.7%	13.4%	36.8%	26.2%
2026-10-17T18:00:00+00:00	4.0%	9.2%	5.8%	13.2%	—	23.2%
2026-10-18T00:00:00+00:00	4.7%	7.3%	2.1%	15.4%	29.3%	21.2%
2026-10-18T06:00:00+00:00	4.1%	7.5%	1.5%	18.1%	—	24.8%
2026-10-18T12:00:00+00:00	3.4%	7.7%	1.3%	16.1%	34.6%	21.4%
2026-10-18T18:00:00+00:00	100.0%	3.1%	0.9%	8.6%	—	—

THE MODEL BOX SCORE

Forecasts & evidence

MODEL	YES	MEAN	SPREAD σ	INITIALIZATION UTC	BRIER ↓
ICON	25%	57.9°F	3.5°F	2026-10-17 12:00	0.0615
IFS HRES	17%	59.1°F	3.7°F	2026-10-17 12:00	0.0279
IFS Ensemble	6%	60.3°F	3.0°F	2026-10-17 00:00	0.0032
NWS forecast	5%	59.0°F	2.1°F	2026-10-18 03:00	0.0027
National Blend	4%	59.0°F	2.0°F	2026-10-17 06:00	0.0015
AIFS Single	2%	63.9°F	3.9°F	2026-10-17 18:00	0.0003
WeatherNext 2	<1%	62.7°F	2.9°F	2026-10-17 12:00	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 ≤ 55°F · KPHL

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-KPHL-20261018-TMAX-LE55
Opened Oct 14 · 10:32 UTC

Original listing: Philadelphia stays cold-for-here: high ≤ 55°F · Sun Oct 18

Original prop, full history & receipt ↗