KSTL / Wed Oct 21 / OFFICIAL STATION RECORD

St. Louis, MOHigh ≥ 75°F

CONSENSUS FORECAST45%Oct 20 · 14:46 UTC

THE FORECAST FIELD

Who takes which side?

0% · NO50%YES · 100%

74%

58%

45%

37%

15%

Consensus

45%

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

AIFSYES 44.2¢Risks 44.25u

ICONNO 55.8¢Risks 55.75u

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

AIFS +55.75u · ICON −55.75u

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 2026-10-20T06:00:00+00:00 · UTC

View the forecast data

UTC	AIFS	ICON	GFS	UKMET	GEM	IFS*
2026-10-06T12:00:00+00:00	0.0%	—	—	—	—	0.6%
2026-10-06T18:00:00+00:00	62.1%	—	—	—	—	—
2026-10-07T00:00:00+00:00	0.7%	—	—	—	—	18.9%
2026-10-07T06:00:00+00:00	2.7%	—	—	—	—	—
2026-10-07T12:00:00+00:00	14.3%	—	—	—	—	18.6%
2026-10-07T18:00:00+00:00	0.4%	—	—	—	—	—
2026-10-08T00:00:00+00:00	1.2%	—	—	—	—	11.2%
2026-10-08T06:00:00+00:00	36.9%	—	—	—	—	—
2026-10-08T12:00:00+00:00	24.4%	—	—	—	—	26.1%
2026-10-08T18:00:00+00:00	19.7%	—	—	—	—	—
2026-10-09T00:00:00+00:00	22.4%	—	—	—	—	26.1%
2026-10-09T06:00:00+00:00	16.9%	—	—	—	—	—
2026-10-09T12:00:00+00:00	25.7%	—	—	—	—	33.0%
2026-10-09T18:00:00+00:00	56.9%	—	—	—	—	—
2026-10-10T00:00:00+00:00	57.4%	—	—	—	—	38.5%
2026-10-10T06:00:00+00:00	43.1%	—	—	—	—	—
2026-10-10T12:00:00+00:00	56.9%	—	—	—	—	43.6%
2026-10-10T18:00:00+00:00	42.5%	—	—	—	—	—
2026-10-11T00:00:00+00:00	57.7%	—	—	—	—	43.4%
2026-10-11T06:00:00+00:00	66.8%	—	34.7%	—	—	—
2026-10-11T12:00:00+00:00	19.7%	—	—	—	—	44.3%
2026-10-11T18:00:00+00:00	27.2%	—	—	—	—	—
2026-10-12T00:00:00+00:00	17.3%	—	3.6%	—	—	51.2%
2026-10-12T06:00:00+00:00	12.8%	—	78.6%	—	—	—
2026-10-12T12:00:00+00:00	32.4%	—	—	—	—	44.6%
2026-10-12T18:00:00+00:00	18.9%	—	—	—	—	—
2026-10-13T00:00:00+00:00	12.8%	—	—	—	—	50.6%
2026-10-13T06:00:00+00:00	35.0%	—	20.2%	—	—	—
2026-10-13T12:00:00+00:00	20.2%	—	17.2%	—	—	43.5%
2026-10-13T18:00:00+00:00	67.3%	—	63.7%	—	—	—
2026-10-14T00:00:00+00:00	71.8%	5.6%	23.8%	—	—	38.0%
2026-10-14T06:00:00+00:00	66.7%	—	90.0%	—	—	—
2026-10-14T12:00:00+00:00	43.7%	33.0%	67.7%	1.0%	—	19.9%
2026-10-14T18:00:00+00:00	49.3%	—	71.1%	—	—	—
2026-10-15T00:00:00+00:00	52.2%	34.3%	59.4%	7.1%	—	26.6%
2026-10-15T06:00:00+00:00	61.1%	—	61.1%	—	—	—
2026-10-15T12:00:00+00:00	49.2%	43.2%	54.6%	17.9%	—	28.3%
2026-10-15T18:00:00+00:00	45.3%	—	56.2%	—	—	—
2026-10-16T00:00:00+00:00	50.0%	35.9%	47.6%	24.2%	—	18.4%
2026-10-16T06:00:00+00:00	45.9%	—	37.2%	—	—	—
2026-10-16T12:00:00+00:00	40.1%	27.9%	51.7%	21.9%	—	25.8%
2026-10-16T18:00:00+00:00	44.9%	6.4%	50.0%	—	—	0.0%
2026-10-17T00:00:00+00:00	38.8%	7.0%	53.5%	17.2%	—	18.4%
2026-10-17T06:00:00+00:00	34.2%	14.0%	59.8%	—	—	17.2%
2026-10-17T12:00:00+00:00	32.2%	9.0%	54.6%	9.4%	—	13.9%
2026-10-17T18:00:00+00:00	33.5%	5.1%	51.9%	—	—	12.7%
2026-10-18T00:00:00+00:00	34.8%	13.1%	56.8%	7.9%	—	14.2%
2026-10-18T06:00:00+00:00	28.2%	11.4%	62.8%	—	—	9.6%
2026-10-18T12:00:00+00:00	31.2%	10.3%	60.2%	3.0%	—	9.8%
2026-10-18T18:00:00+00:00	34.5%	10.6%	63.5%	—	—	—
2026-10-19T00:00:00+00:00	37.1%	24.7%	67.9%	6.6%	—	16.2%
2026-10-19T06:00:00+00:00	23.1%	15.4%	70.4%	0.0%	—	7.9%
2026-10-19T12:00:00+00:00	28.0%	16.0%	64.8%	1.7%	0.0%	9.4%
2026-10-19T18:00:00+00:00	37.0%	30.4%	71.7%	3.1%	—	11.9%
2026-10-20T00:00:00+00:00	40.1%	21.7%	73.4%	5.5%	33.1%	18.2%
2026-10-20T06:00:00+00:00	22.8%	—	70.9%	6.8%	—	8.2%

THE MODEL BOX SCORE

Forecasts & evidence

MODEL	YES	MEAN	SPREAD σ	INITIALIZATION UTC	BRIER ↓
AIFS Single	74%	77.0°F	3.9°F	2026-10-20 00:00	Pending
WeatherNext 2	58%	75.1°F	2.9°F	2026-10-20 00:00	Pending
NWS forecast	56%	75.0°F	3.1°F	2026-10-20 03:00	Pending
IFS HRES	45%	74.0°F	3.7°F	2026-10-20 00:00	Pending
National Blend	41%	74.0°F	2.2°F	2026-10-20 06:00	Pending
IFS Ensemble	37%	73.2°F	3.8°F	2026-10-20 00:00	Pending
ICON	15%	70.8°F	3.5°F	2026-10-20 00:00	Pending

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 ≥ 75°F · KSTL

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-KSTL-20261021-TMAX-GE75
Opened Oct 19 · 15:13 UTC

Original listing: St. Louis high ≥ 75°F · Wed Oct 21

Original prop, full history & receipt ↗