Highest temperature in Chicago on Oct 18, 2026: 63° to 64° — it happened. How PBE scored.
63° to 64°: YES. PBE's final pre-resolution forecast was 31% against a 60% market. The designated forecasts, the market at the same moments, and the scores — fixed before the outcome.
Photo: J. Crocker · Attribution · Wikimedia Commons
Resolved Oct 19 12:08Z · verified against NWS CLI CLIMDW product 202610190631-KLOT-CDUS43-CLIMDW
Highest temperature in Chicago on Oct 18, 2026?
63° to 64° · RESOLVED
Quick read
- Result: 63° to 64°: YES; official check 64 degF agrees with the venue.
- PBE at the final pre-resolution snapshot: 31%; market at that moment 60%.
- Mean Brier at the final checkpoint: PBE 0.099, market 0.054 (n=6).
- Scoring snapshots were fixed by rule (designation/1) before the outcome existed.
What happened
Highest temperature in Chicago on Oct 18, 2026 resolved with 63° to 64°: YES. The venue settled at Oct 19 12:08Z (expiration value 64.00); PropBetEdge's independent check — NWS CLI CLIMDW product 202610190631-KLOT-CDUS43-CLIMDW — recorded 64 degF, which agrees with the settlement (source).
What PBE said before it happened
The snapshots that count were fixed by rule before the outcome: the first published forecast, the forecast in force 24 hours before the reference time (only if one existed), and the last forecast before it. Each is shown with the Kalshi mid captured at the same moment.
| Outcome | Result | First published | T−24 h | Final pre-resolution |
|---|---|---|---|---|
| 61° to 62° | NO | 22% | — | 22% (mkt 7%) |
| 60° or below | NO | 12% | — | 12% (mkt 2%) |
| 63° to 64° | YES | 31% | — | 31% (mkt 60%) |
| 65° to 66° | NO | 21% | — | 21% (mkt 32%) |
| 67° to 68° | NO | 10% | — | 10% (mkt 2%) |
| 69° or above | NO | 5% (mkt 2%) | — | 5% |
How it scored
Scores compare PBE and the market on the same designated snapshot — a lower Brier score or log loss is better. At the final pre-resolution checkpoint PBE's mean Brier score across 6 contracts was 0.099 against 0.054 for the market. One event is not evidence of skill in either direction.
| Checkpoint | Method | PBE | Market | n (PBE) | n (market) |
|---|---|---|---|---|---|
| First published | Brier | 0.099 | 0.000 | 6 | 1 |
| First published | Log loss | 0.323 | 0.020 | 6 | 1 |
| Final pre-resolution | Brier | 0.099 | 0.054 | 6 | 5 |
| Final pre-resolution | Log loss | 0.323 | 0.200 | 6 | 5 |
This event adds 6 resolved contracts to the model's live record (618 resolved in total). Live calibration is published once 30 have resolved.
Evidence & method
What this story is based on. Every value above was read from these immutable records.
| Outcome | Model | Snapshot | Compared with | Captured | Data cutoff | Market |
|---|---|---|---|---|---|---|
| 61° to 62° | pbe-weather-maxtemp@1.1.0 · RESEARCH | 592d4e27-91bd-4056-a49e-5db07a178f28 | 47f18a12-d8d8-410d-9a74-56e5976678c1 | Oct 18 05:00Z | Oct 18 05:00Z | 7% |
| 60° or below | pbe-weather-maxtemp@1.1.0 · RESEARCH | c653f2e9-6d5d-4d22-8a38-fe9f45541c0d | 27bf4b72-d29e-43da-987e-cc6e9f10bd07 | Oct 18 05:00Z | Oct 18 05:00Z | 2% |
| 63° to 64° | pbe-weather-maxtemp@1.1.0 · RESEARCH | 23746229-eaf2-4ca6-addc-94d48a20f803 | ee0d60ef-7268-41ec-949c-0d9c9ac96f0b | Oct 18 05:00Z | Oct 18 05:00Z | 60% |
| 65° to 66° | pbe-weather-maxtemp@1.1.0 · RESEARCH | df0d4e22-50df-4de2-9510-2bc85f50bbc9 | 9abe13ff-ed6d-49ca-93bc-587db64ac17c | Oct 18 05:00Z | Oct 18 05:00Z | 32% |
| 67° to 68° | pbe-weather-maxtemp@1.1.0 · RESEARCH | 1a136c57-8ffc-4f3b-b31e-ffa9854c66d9 | 58649afd-701c-4dbb-bf59-75ab0cdb8174 | Oct 18 05:00Z | Oct 18 05:00Z | 2% |
| 69° or above | pbe-weather-maxtemp@1.1.0 · RESEARCH | c195b86d-7c57-426c-ac2b-b721ff625677 | 047c0d40-5ae2-417e-aefc-b89e33b7117f | Oct 18 05:00Z | Oct 18 05:00Z | — |
Source families: NWS CLI CLIMDW product 202610190631-KLOT-CDUS43-CLIMDW. Market = Kalshi mid captured with each snapshot.
- Resolves on
- The Weather Company (weather.com/kalshi) — The Weather Company daily maximum temperature for CLIMDW (weather.com/kalshi)
- Independent check
- NWS Daily Climate Report CLIMDW (WFO LOT); NOAA RCC-ACIS USW00014819
- Measurement
- Maximum temperature for the climate day 2026-10-18, 00:00-24:00 local standard time (UTC-6)
- Rounding
- Whole degrees Fahrenheit as reported; preliminary values may differ by rounding/conversion
- Exceptions
- Preliminary data may be revised; the exchange may hold expiration until a non-erroneous revision, else last fair price
- Pre-window only; no current-conditions input
- Guidance can run cold/hot in unusual regimes (see LA diagnostic, 2026-10-04)
Weather · daily high — inputs: National Blend of Models day max (GFS MOS fallback) + station empirical guidance-error tables. This model on the research board →
Market prices are a benchmark only and never enter a PropBetEdge model. Research-stage probabilities; not advice.