KSTL / Wed Oct 21 / OFFICIAL STATION RECORD

St. Louis, MOHigh ≥ 81°F

CONSENSUS FORECAST2%Oct 19 · 04:31 UTC

THE FORECAST FIELD

Who takes which side?

0% · NO50%YES · 100%

16%

<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

AIFSYES 8.4¢Risks 4.20u

ICONNO 91.6¢Risks 45.80u

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

AIFS +45.80u · ICON −45.80u

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%	—	—	—	—	0.1%
2026-10-06T18:00:00+00:00	31.1%	—	—	—	—	—
2026-10-07T00:00:00+00:00	0.1%	—	—	—	—	4.7%
2026-10-07T06:00:00+00:00	0.3%	—	—	—	—	—
2026-10-07T12:00:00+00:00	3.1%	—	—	—	—	4.5%
2026-10-07T18:00:00+00:00	0.0%	—	—	—	—	—
2026-10-08T00:00:00+00:00	0.1%	—	—	—	—	2.2%
2026-10-08T06:00:00+00:00	12.8%	—	—	—	—	—
2026-10-08T12:00:00+00:00	6.8%	—	—	—	—	7.5%
2026-10-08T18:00:00+00:00	4.9%	—	—	—	—	—
2026-10-09T00:00:00+00:00	5.9%	—	—	—	—	7.5%
2026-10-09T06:00:00+00:00	3.9%	—	—	—	—	—
2026-10-09T12:00:00+00:00	7.3%	—	—	—	—	10.8%
2026-10-09T18:00:00+00:00	26.5%	—	—	—	—	—
2026-10-10T00:00:00+00:00	27.0%	—	—	—	—	13.7%
2026-10-10T06:00:00+00:00	16.5%	—	—	—	—	—
2026-10-10T12:00:00+00:00	26.5%	—	—	—	—	16.8%
2026-10-10T18:00:00+00:00	15.7%	—	—	—	—	—
2026-10-11T00:00:00+00:00	26.3%	—	—	—	—	16.0%
2026-10-11T06:00:00+00:00	34.2%	—	10.9%	—	—	—
2026-10-11T12:00:00+00:00	4.4%	—	—	—	—	16.0%
2026-10-11T18:00:00+00:00	7.0%	—	—	—	—	—
2026-10-12T00:00:00+00:00	3.4%	—	0.4%	—	—	19.7%
2026-10-12T06:00:00+00:00	2.1%	—	45.8%	—	—	—
2026-10-12T12:00:00+00:00	8.6%	—	—	—	—	14.7%
2026-10-12T18:00:00+00:00	3.5%	—	—	—	—	—
2026-10-13T00:00:00+00:00	1.9%	—	—	—	—	17.6%
2026-10-13T06:00:00+00:00	8.9%	—	3.6%	—	—	—
2026-10-13T12:00:00+00:00	3.5%	—	2.7%	—	—	12.7%
2026-10-13T18:00:00+00:00	29.2%	—	25.8%	—	—	—
2026-10-14T00:00:00+00:00	33.0%	0.4%	4.2%	—	—	9.3%
2026-10-14T06:00:00+00:00	27.3%	—	59.6%	—	—	—
2026-10-14T12:00:00+00:00	11.2%	6.7%	27.5%	0.0%	—	2.9%
2026-10-14T18:00:00+00:00	13.6%	—	30.1%	—	—	—
2026-10-15T00:00:00+00:00	14.8%	6.6%	19.4%	0.5%	—	4.2%
2026-10-15T06:00:00+00:00	20.0%	—	20.0%	—	—	—
2026-10-15T12:00:00+00:00	12.2%	9.3%	15.1%	1.9%	—	4.2%
2026-10-15T18:00:00+00:00	9.8%	—	15.4%	—	—	—
2026-10-16T00:00:00+00:00	11.5%	5.9%	10.4%	2.9%	—	1.8%
2026-10-16T06:00:00+00:00	9.2%	—	6.0%	—	—	—
2026-10-16T12:00:00+00:00	6.6%	3.3%	11.2%	2.1%	—	2.8%
2026-10-16T18:00:00+00:00	7.8%	0.2%	9.9%	—	—	0.0%
2026-10-17T00:00:00+00:00	5.4%	0.3%	10.9%	1.2%	—	1.3%
2026-10-17T06:00:00+00:00	3.9%	0.8%	13.5%	—	—	1.1%
2026-10-17T12:00:00+00:00	3.2%	0.3%	10.2%	0.3%	—	0.7%
2026-10-17T18:00:00+00:00	3.2%	0.1%	8.4%	—	—	0.5%
2026-10-18T00:00:00+00:00	3.2%	0.5%	9.8%	0.2%	—	0.6%
2026-10-18T06:00:00+00:00	1.9%	0.3%	11.9%	—	—	0.2%
2026-10-18T12:00:00+00:00	2.1%	0.2%	9.8%	0.0%	—	0.2%
2026-10-18T18:00:00+00:00	2.3%	0.2%	10.6%	—	—	—
2026-10-19T00:00:00+00:00	2.4%	1.0%	11.9%	0.1%	—	0.4%
2026-10-19T06:00:00+00:00	0.8%	0.3%	12.3%	0.0%	—	0.1%
2026-10-19T12:00:00+00:00	1.0%	0.3%	8.5%	0.0%	0.0%	0.1%
2026-10-19T18:00:00+00:00	1.6%	1.0%	10.8%	0.0%	—	0.1%
2026-10-20T00:00:00+00:00	1.7%	0.4%	10.6%	0.0%	1.0%	0.3%
2026-10-20T06:00:00+00:00	0.4%	—	8.2%	0.0%	—	0.0%

THE MODEL BOX SCORE

Forecasts & evidence

MODEL	YES	MEAN	SPREAD σ	INITIALIZATION UTC	BRIER ↓
AIFS Single	16%	76.3°F	4.3°F	2026-10-18 18:00	Pending
NWS forecast	15%	77.0°F	3.4°F	2026-10-19 03:00	Pending
National Blend	6%	77.0°F	2.2°F	2026-10-18 06:00	Pending
WeatherNext 2	2%	73.8°F	3.4°F	2026-10-18 12:00	Pending
IFS HRES	2%	71.2°F	4.5°F	2026-10-18 12:00	Pending
IFS Ensemble	<1%	71.9°F	3.5°F	2026-10-18 00:00	Pending
ICON	<1%	70.3°F	4.0°F	2026-10-18 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 ≥ 81°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-GE81
Opened Oct 14 · 10:33 UTC

Original listing: St. Louis runs hot-for-here: 81°F+ · Wed Oct 21

Original prop, full history & receipt ↗