KSTL / Thu Oct 22 / OFFICIAL STATION RECORD

St. Louis, MOHigh ≥ 77°F

CONSENSUS FORECAST39%Oct 20 · 03:18 UTC

THE FORECAST FIELD

Who takes which side?

0% · NO50%YES · 100%

65%

48%

20%

19%

18%

Consensus

39%

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 41.1¢Risks 41.15u

ICONNO 58.9¢Risks 58.85u

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

AIFS +58.85u · ICON −58.85u

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*
2026-10-07T12:00:00+00:00	0.0%	—	—	—	—	0.2%
2026-10-07T18:00:00+00:00	2.5%	—	—	—	—	—
2026-10-08T00:00:00+00:00	2.7%	—	—	—	—	6.8%
2026-10-08T06:00:00+00:00	20.1%	—	—	—	—	—
2026-10-08T12:00:00+00:00	27.0%	—	—	—	—	16.5%
2026-10-08T18:00:00+00:00	3.7%	—	—	—	—	—
2026-10-09T00:00:00+00:00	16.9%	—	—	—	—	14.3%
2026-10-09T06:00:00+00:00	18.6%	—	—	—	—	—
2026-10-09T12:00:00+00:00	24.0%	—	—	—	—	16.9%
2026-10-09T18:00:00+00:00	20.1%	—	—	—	—	—
2026-10-10T00:00:00+00:00	11.0%	—	—	—	—	14.6%
2026-10-10T06:00:00+00:00	43.1%	—	—	—	—	—
2026-10-10T12:00:00+00:00	61.5%	—	—	—	—	22.0%
2026-10-10T18:00:00+00:00	25.2%	—	—	—	—	—
2026-10-11T00:00:00+00:00	18.2%	—	—	—	—	18.6%
2026-10-11T06:00:00+00:00	48.4%	—	—	—	—	—
2026-10-11T12:00:00+00:00	39.5%	—	—	—	—	23.9%
2026-10-11T18:00:00+00:00	31.7%	—	—	—	—	—
2026-10-12T00:00:00+00:00	45.1%	—	—	—	—	37.5%
2026-10-12T06:00:00+00:00	33.7%	—	—	—	—	—
2026-10-12T12:00:00+00:00	38.8%	—	—	—	—	35.6%
2026-10-12T18:00:00+00:00	42.0%	—	—	—	—	—
2026-10-13T00:00:00+00:00	26.4%	—	—	—	—	38.4%
2026-10-13T06:00:00+00:00	38.2%	—	—	—	—	—
2026-10-13T12:00:00+00:00	33.5%	—	—	—	—	34.6%
2026-10-13T18:00:00+00:00	39.0%	—	5.4%	—	—	—
2026-10-14T00:00:00+00:00	69.3%	—	25.9%	—	—	26.4%
2026-10-14T06:00:00+00:00	65.0%	—	44.3%	—	—	—
2026-10-14T12:00:00+00:00	54.5%	—	41.0%	—	—	12.3%
2026-10-14T18:00:00+00:00	63.0%	—	76.8%	—	—	—
2026-10-15T00:00:00+00:00	53.4%	0.1%	45.3%	—	—	24.9%
2026-10-15T06:00:00+00:00	58.2%	—	45.2%	—	—	—
2026-10-15T12:00:00+00:00	57.7%	46.5%	55.6%	0.7%	—	29.8%
2026-10-15T18:00:00+00:00	50.0%	—	61.3%	—	—	—
2026-10-16T00:00:00+00:00	51.5%	31.0%	60.8%	10.6%	—	20.4%
2026-10-16T06:00:00+00:00	51.5%	—	62.5%	—	—	—
2026-10-16T12:00:00+00:00	49.2%	32.3%	59.8%	26.4%	—	30.3%
2026-10-16T18:00:00+00:00	51.6%	—	60.0%	—	—	—
2026-10-17T00:00:00+00:00	39.7%	13.6%	61.8%	12.7%	—	18.9%
2026-10-17T06:00:00+00:00	34.9%	—	53.3%	—	—	17.9%
2026-10-17T12:00:00+00:00	26.5%	4.9%	50.0%	9.3%	—	13.4%
2026-10-17T18:00:00+00:00	28.8%	3.6%	57.6%	—	—	11.9%
2026-10-18T00:00:00+00:00	24.1%	6.5%	57.0%	8.0%	—	15.1%
2026-10-18T06:00:00+00:00	17.8%	6.6%	65.8%	—	—	9.6%
2026-10-18T12:00:00+00:00	17.8%	7.0%	57.3%	2.9%	—	9.0%
2026-10-18T18:00:00+00:00	18.4%	15.4%	55.7%	—	—	—
2026-10-19T00:00:00+00:00	27.9%	22.5%	62.4%	6.5%	—	14.2%
2026-10-19T06:00:00+00:00	20.4%	17.0%	64.7%	—	—	0.0%
2026-10-19T12:00:00+00:00	23.5%	12.8%	61.2%	4.2%	—	10.8%
2026-10-19T18:00:00+00:00	32.6%	27.1%	65.5%	—	—	12.7%
2026-10-20T00:00:00+00:00	37.1%	28.2%	67.9%	4.0%	39.2%	16.2%
2026-10-20T06:00:00+00:00	26.7%	—	62.2%	0.0%	—	9.7%

THE MODEL BOX SCORE

Forecasts & evidence

MODEL	YES	MEAN	SPREAD σ	INITIALIZATION UTC	BRIER ↓
AIFS Single	65%	78.1°F	4.3°F	2026-10-19 18:00	Pending
National Blend	59%	77.0°F	2.2°F	2026-10-19 06:00	Pending
NWS forecast	55%	77.0°F	3.9°F	2026-10-19 14:00	Pending
WeatherNext 2	48%	76.3°F	3.4°F	2026-10-19 12:00	Pending
IFS Ensemble	20%	73.6°F	3.5°F	2026-10-19 00:00	Pending
IFS HRES	19%	72.6°F	4.5°F	2026-10-19 12:00	Pending
ICON	18%	72.8°F	4.0°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-20261022-TMAX-GE77
Opened Oct 15 · 11:39 UTC

Original listing: St. Louis high ≥ 77°F · Thu Oct 22

Original prop, full history & receipt ↗