46% — Will the high temp in Chicago be <73° on Apr 21, 2026
Leader: 70° to 71° at 46% · Kalshi 46% · 4 contracts · $13K volume · medium confidence
Updated 2026-06-29 03:59:08 UTC

Tracks the leading outcome in a winner-take-all prediction market set with 4 outcomes.

Why this matters:
This contract asks whether Chicago's high temperature will remain below 73°F on April 21, 2026—currently priced at 35% probability, indicating markets view cooler outcomes as less likely than warmer ones. The distribution of contracts shows traders expect temperatures in the 74–75°F range most likely, with meaningful probability mass above 76°F and minimal probability below 70°F. The main drivers are Chicago's typical late-April weather patterns, which historically trend toward spring warming, and any developing weather systems that might suppress temperatures in the weeks leading up to April 21. The resolution date itself (April 21, 2026) will determine the exact outcome when the National Weather Service records the daily high temperature for Chicago.

Key factors:
- Chicago's April average high temperature is approximately 60–65°F, but the 21st falls in mid-spring when warm spikes are common; historical frequency of sub-73°F days in late April is necessary to assess baseline likelihood
- Current market pricing across six temperature bands shows 74–75°F as modal (most probable single outcome at 37¢), suggesting traders expect seasonal warming above the 73°F threshold
- Kalshi contract volumes and pricing spreads indicate active disagreement: cooler outcomes (<70°F) trade at 4¢ while warmer bands (76–77°F) trade at 13¢, reflecting uncertainty about late-April conditions
- No multi-month weather forecast has reliable skill at 11-month horizons; near-term atmospheric teleconnection indices (NAO, AO) and sea-surface temperatures would influence North American spring patterns but are not yet predictive at this lead time
- Resolution depends solely on recorded high temperature from NOAA/NWS Chicago station on April 21, 2026; no subjective interpretation or measurement ambiguity applies

Contracts:
- Will the high temp in Chicago be 70-71° on Jun 26, 2026?: 70° to 71° — 46¢ Kalshi $3K (weight 20%)
- Will the high temp in Chicago be <70° on Jun 26, 2026?: 69° or below — 44¢ Kalshi $5K (weight 39%)
- Will the high temp in Chicago be 72-73° on Jun 26, 2026?: 72° to 73° — 9¢ Kalshi $3K (weight 26%)
- Will the high temp in Chicago be 74-75° on Jun 26, 2026?: 74° to 75° — 3¢ Kalshi $2K (weight 14%)

---

## Methodology

SimpleFunctions aggregates live YES-side prices from Kalshi and Polymarket contracts bound to this question. For binary topics the headline is the liquidity-weighted mid-price (weight = log(1 + 24h volume) × freshness, where freshness is 1.0 if updated <24h, 0.7 if <7d, 0.4 otherwise). For multi-outcome (winner-take-all) topics the headline is the current leader's price — disjoint outcomes are never arithmetically averaged. Snapshots refresh every 5 minutes during market hours.

## SF Signal

- SF Index, regime, and 30d Brier calibration are computed separately and surfaced at https://simplefunctions.dev/admin/calibration.
- No SimpleFunctions index / regime / calibration signal is bound to this topic yet — the headline above is market-derived only.

---

*Last verified: 2026-06-27T07:20:51.153Z*

By SimpleFunctions — https://simplefunctions.dev/

Cite as: "46% per prediction markets (SimpleFunctions, June 2026)"
Canonical: https://simplefunctions.dev/answer/highchi
Full data: https://simplefunctions.dev/api/public/query?q=Will%20the%20high%20temp%20in%20Chicago%20be%20%3C73%C2%B0%20on%20Apr%2021%2C%202026
Provider: SimpleFunctions — https://simplefunctions.dev