KSTL / Tue Oct 20 / OFFICIAL STATION RECORD

St. Louis, MOHigh ≥ 77°F

CONSENSUS FORECAST17%Oct 15 · 14:48 UTC

THE FORECAST FIELD

Who takes which side?

0% · NO50%YES · 100%

51%

22%

20%

12%

Consensus

17%

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 28.8¢Risks 28.85u

EPSNO 71.2¢Risks 71.15u

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

AIFS +71.15u · EPS −71.15u

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*
2026-10-05T12:00:00+00:00	0.0%	—	—	—	—	0.2%
2026-10-05T18:00:00+00:00	14.9%	—	—	—	—	—
2026-10-06T00:00:00+00:00	2.7%	—	—	—	—	10.5%
2026-10-06T06:00:00+00:00	41.5%	—	—	—	—	—
2026-10-06T12:00:00+00:00	1.9%	—	—	—	—	13.4%
2026-10-06T18:00:00+00:00	43.6%	—	—	—	—	—
2026-10-07T00:00:00+00:00	3.3%	—	—	—	—	11.0%
2026-10-07T06:00:00+00:00	1.9%	—	—	—	—	—
2026-10-07T12:00:00+00:00	5.9%	—	—	—	—	10.5%
2026-10-07T18:00:00+00:00	0.2%	—	—	—	—	—
2026-10-08T00:00:00+00:00	6.9%	—	—	—	—	9.1%
2026-10-08T06:00:00+00:00	7.1%	—	—	—	—	—
2026-10-08T12:00:00+00:00	7.1%	—	—	—	—	16.2%
2026-10-08T18:00:00+00:00	4.4%	—	—	—	—	—
2026-10-09T00:00:00+00:00	12.6%	—	—	—	—	22.0%
2026-10-09T06:00:00+00:00	4.7%	—	—	—	—	—
2026-10-09T12:00:00+00:00	8.6%	—	—	—	—	24.3%
2026-10-09T18:00:00+00:00	15.1%	—	—	—	—	—
2026-10-10T00:00:00+00:00	31.9%	—	—	—	—	35.0%
2026-10-10T06:00:00+00:00	11.7%	—	—	—	—	—
2026-10-10T12:00:00+00:00	34.0%	—	—	—	—	31.9%
2026-10-10T18:00:00+00:00	26.2%	—	—	—	—	—
2026-10-11T00:00:00+00:00	27.3%	—	—	—	—	29.3%
2026-10-11T06:00:00+00:00	44.6%	—	18.1%	—	—	—
2026-10-11T12:00:00+00:00	43.4%	—	—	—	—	27.7%
2026-10-11T18:00:00+00:00	37.9%	—	—	—	—	—
2026-10-12T00:00:00+00:00	17.6%	—	33.0%	—	—	35.9%
2026-10-12T06:00:00+00:00	8.2%	—	63.8%	—	—	—
2026-10-12T12:00:00+00:00	2.2%	—	36.6%	—	—	25.7%
2026-10-12T18:00:00+00:00	7.4%	—	56.0%	—	—	—
2026-10-13T00:00:00+00:00	45.3%	0.1%	43.9%	—	—	28.2%
2026-10-13T06:00:00+00:00	41.8%	—	18.4%	—	—	—
2026-10-13T12:00:00+00:00	42.3%	21.4%	18.9%	0.2%	—	26.3%
2026-10-13T18:00:00+00:00	32.0%	—	12.9%	—	—	—
2026-10-14T00:00:00+00:00	31.0%	28.5%	0.7%	9.6%	—	9.6%
2026-10-14T06:00:00+00:00	29.3%	—	56.0%	—	—	—
2026-10-14T12:00:00+00:00	15.1%	9.0%	46.9%	3.3%	—	3.9%
2026-10-14T18:00:00+00:00	15.9%	—	46.1%	—	—	—
2026-10-15T00:00:00+00:00	18.9%	6.2%	42.1%	2.5%	—	5.5%
2026-10-15T06:00:00+00:00	25.0%	—	10.6%	—	—	—
2026-10-15T12:00:00+00:00	14.8%	8.3%	21.9%	2.2%	—	6.6%
2026-10-15T18:00:00+00:00	11.9%	2.5%	28.1%	—	—	—
2026-10-16T00:00:00+00:00	13.1%	7.3%	18.4%	2.3%	—	3.6%
2026-10-16T06:00:00+00:00	13.0%	3.1%	9.2%	—	—	3.4%
2026-10-16T12:00:00+00:00	13.4%	2.5%	17.2%	2.8%	—	4.3%
2026-10-16T18:00:00+00:00	12.7%	2.1%	22.4%	—	—	4.0%
2026-10-17T00:00:00+00:00	11.6%	1.0%	21.8%	2.1%	—	2.7%
2026-10-17T06:00:00+00:00	8.8%	0.7%	24.1%	—	—	1.6%
2026-10-17T12:00:00+00:00	5.5%	0.7%	23.5%	0.5%	0.0%	0.9%
2026-10-17T18:00:00+00:00	6.2%	0.1%	21.3%	—	—	1.0%
2026-10-18T00:00:00+00:00	5.0%	1.1%	23.0%	0.5%	—	1.1%
2026-10-18T06:00:00+00:00	2.9%	0.8%	21.4%	0.0%	—	0.6%
2026-10-18T12:00:00+00:00	3.3%	0.9%	28.9%	0.2%	0.0%	0.5%
2026-10-18T18:00:00+00:00	4.5%	2.3%	22.5%	0.2%	—	—
2026-10-19T00:00:00+00:00	4.9%	6.3%	23.6%	0.3%	5.9%	1.4%
2026-10-19T06:00:00+00:00	1.3%	4.0%	24.8%	0.1%	—	0.3%
2026-10-19T12:00:00+00:00	1.4%	2.6%	24.0%	0.1%	4.0%	0.4%
2026-10-19T18:00:00+00:00	3.2%	5.8%	21.1%	0.2%	—	0.7%
2026-10-20T00:00:00+00:00	2.7%	7.8%	20.2%	0.5%	7.8%	1.1%
2026-10-20T06:00:00+00:00	0.9%	—	15.3%	0.4%	—	0.2%

THE MODEL BOX SCORE

Forecasts & evidence

MODEL	YES	MEAN	SPREAD σ	INITIALIZATION UTC	BRIER ↓
NWS forecast	54%	77.0°F	5.2°F	2026-10-15 03:00	Pending
AIFS Single	51%	76.6°F	5.0°F	2026-10-15 06:00	Pending
WeatherNext 2	22%	73.4°F	4.1°F	2026-10-15 00:00	Pending
ICON	20%	71.5°F	6.0°F	2026-10-15 00:00	Pending
National Blend	15%	73.0°F	3.3°F	2026-10-15 06:00	Pending
IFS HRES	12%	69.8°F	5.8°F	2026-10-15 00:00	Pending
IFS Ensemble	7%	72.2°F	2.9°F	2026-10-15 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 ≥ 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-20261020-TMAX-GE77
Opened Oct 14 · 15:12 UTC

Original listing: St. Louis high ≥ 77°F · Tue Oct 20

Original prop, full history & receipt ↗