KSTL / Fri Oct 23 / OFFICIAL STATION RECORD

St. Louis, MOHigh ≥ 77°F

CONSENSUS FORECAST36%Oct 20 · 03:18 UTC

THE FORECAST FIELD

Who takes which side?

0% · NO50%YES · 100%

49%

45%

20%

19%

10%

Consensus

36%

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 29.5¢Risks 29.55u

HRESNO 70.5¢Risks 70.45u

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

AIFS +70.45u · HRES −70.45u

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*
2026-10-08T12:00:00+00:00	0.0%	—	—	—	—	0.2%
2026-10-08T18:00:00+00:00	9.6%	—	—	—	—	—
2026-10-09T00:00:00+00:00	1.6%	—	—	—	—	11.5%
2026-10-09T06:00:00+00:00	11.2%	—	—	—	—	—
2026-10-09T12:00:00+00:00	25.7%	—	—	—	—	7.5%
2026-10-09T18:00:00+00:00	47.9%	—	—	—	—	—
2026-10-10T00:00:00+00:00	22.4%	—	—	—	—	10.5%
2026-10-10T06:00:00+00:00	52.7%	—	—	—	—	—
2026-10-10T12:00:00+00:00	33.0%	—	—	—	—	11.0%
2026-10-10T18:00:00+00:00	50.0%	—	—	—	—	—
2026-10-11T00:00:00+00:00	29.2%	—	—	—	—	9.8%
2026-10-11T06:00:00+00:00	40.0%	—	—	—	—	—
2026-10-11T12:00:00+00:00	42.6%	—	—	—	—	12.3%
2026-10-11T18:00:00+00:00	14.3%	—	—	—	—	—
2026-10-12T00:00:00+00:00	35.9%	—	—	—	—	29.7%
2026-10-12T06:00:00+00:00	0.3%	—	—	—	—	—
2026-10-12T12:00:00+00:00	56.9%	—	—	—	—	31.0%
2026-10-12T18:00:00+00:00	42.5%	—	—	—	—	—
2026-10-13T00:00:00+00:00	21.6%	—	—	—	—	31.0%
2026-10-13T06:00:00+00:00	46.1%	—	—	—	—	—
2026-10-13T12:00:00+00:00	68.1%	—	—	—	—	30.4%
2026-10-13T18:00:00+00:00	70.4%	—	0.1%	—	—	—
2026-10-14T00:00:00+00:00	71.2%	—	0.5%	—	—	18.5%
2026-10-14T06:00:00+00:00	71.5%	—	63.4%	—	—	—
2026-10-14T12:00:00+00:00	72.4%	—	—	—	—	7.4%
2026-10-14T18:00:00+00:00	65.6%	—	78.5%	—	—	—
2026-10-15T00:00:00+00:00	62.4%	—	—	—	—	21.1%
2026-10-15T06:00:00+00:00	72.9%	—	55.7%	—	—	—
2026-10-15T12:00:00+00:00	60.9%	—	6.9%	—	—	23.6%
2026-10-15T18:00:00+00:00	55.3%	—	66.7%	—	—	—
2026-10-16T00:00:00+00:00	56.1%	0.1%	63.3%	—	—	22.3%
2026-10-16T06:00:00+00:00	56.9%	—	61.6%	—	—	—
2026-10-16T12:00:00+00:00	43.0%	22.4%	65.1%	1.2%	—	33.6%
2026-10-16T18:00:00+00:00	50.0%	—	64.0%	—	—	—
2026-10-17T00:00:00+00:00	35.7%	11.7%	67.0%	18.9%	—	16.1%
2026-10-17T06:00:00+00:00	30.0%	—	67.3%	—	—	—
2026-10-17T12:00:00+00:00	22.8%	1.7%	56.8%	2.2%	—	11.4%
2026-10-17T18:00:00+00:00	26.6%	—	63.0%	—	—	5.4%
2026-10-18T00:00:00+00:00	21.8%	6.2%	61.8%	8.1%	—	12.7%
2026-10-18T06:00:00+00:00	16.8%	—	68.8%	—	—	7.0%
2026-10-18T12:00:00+00:00	16.2%	6.3%	63.9%	3.6%	—	8.3%
2026-10-18T18:00:00+00:00	14.7%	3.4%	56.8%	—	—	—
2026-10-19T00:00:00+00:00	17.8%	14.1%	62.9%	2.1%	—	10.5%
2026-10-19T06:00:00+00:00	13.0%	12.1%	67.4%	—	—	—
2026-10-19T12:00:00+00:00	15.4%	9.0%	63.6%	2.8%	—	6.1%
2026-10-19T18:00:00+00:00	21.0%	17.1%	68.2%	—	—	7.0%
2026-10-20T00:00:00+00:00	27.1%	12.6%	68.7%	5.4%	34.8%	12.6%
2026-10-20T06:00:00+00:00	22.6%	—	62.8%	—	—	6.0%

THE MODEL BOX SCORE

Forecasts & evidence

MODEL	YES	MEAN	SPREAD σ	INITIALIZATION UTC	BRIER ↓
National Blend	59%	77.0°F	2.2°F	2026-10-19 06:00	Pending
NWS forecast	54%	77.0°F	4.5°F	2026-10-19 14:00	Pending
AIFS Single	49%	76.4°F	4.6°F	2026-10-19 18:00	Pending
WeatherNext 2	45%	76.0°F	3.7°F	2026-10-19 12:00	Pending
ICON	20%	72.4°F	4.9°F	2026-10-19 12:00	Pending
IFS Ensemble	19%	73.6°F	3.3°F	2026-10-19 00:00	Pending
IFS HRES	10%	70.1°F	5.0°F	2026-10-19 12:00	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 ≥ 77°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-20261023-TMAX-GE77
Opened Oct 19 · 15:13 UTC

Original listing: St. Louis high ≥ 77°F · Fri Oct 23

Original prop, full history & receipt ↗