Prediction Markets Morning — 2026-09-23
Kalshi weather and Trump-related markets surge; Polymarket esports and tennis see major swings.
Kalshi weather and Trump-related markets surge; Polymarket esports and tennis see major swings.
The Overnight Picture
Data for this briefing was frozen at 08:04 ET on September 23, 2026. The market landscape reflects a mix of settled outcomes in sports and gaming, alongside continued speculation on political and weather events.
Top Kalshi Movers
Weather markets dominated the top movers list, with 'Will it rain in Philadelphia' jumping 86.0 points to 99.0% and 'Will it rain in Washington DC' rising 43.0 points to 99.0%. Political commentary markets also saw massive gains, as 'Will Trump say Antifa before Oct 1' surged 84.0 points to 99.0%, and 'Will Trump say Ceasefire before Sep 28' climbed 60.0 points to 99.0%.
In entertainment and sports, 'Heart of the Beast Rotten Tomatoes score' markets showed strong upward momentum across multiple strike prices, gaining between 35.0 and 66.5 points. Tennis results were decisive, with Murphy Cassone winning moving up 51.0 points to 99.0%, while Clement Tabur winning collapsed by 52.0 points to 1.0%.
| # | Market | Probability | 24h move | Significance | Volume |
|---|---|---|---|---|---|
| 1 | Will it rain in Philadelphia on Sep 23, 2026? | 99.0% | +86.0 pts | 100 | $19,245 |
| 2 | Will Trump say "Antifa" before Oct 1, 2026? | 99.0% | +84.0 pts | 100 | $12,406 |
| 3 | Heart of the Beast Rotten Tomatoes score? | 98.5% | +51.5 pts | 100 | $16,856 |
| 4 | Will Trump say "Antifa" before Sep 28, 2026? | 99.0% | +82.0 pts | 100 | $3,617 |
| 5 | Heart of the Beast Rotten Tomatoes score? | 96.5% | +66.5 pts | 99 | $9,406 |
| 6 | Clement Tabur wins | 1.0% | −52.0 pts | 99 | $1.41M |
| 7 | Murphy Cassone wins | 99.0% | +51.0 pts | 99 | $1.61M |
| 8 | Will Trump say "Ceasefire" before Sep 28, 2026? | 99.0% | +60.0 pts | 97 | $2,200 |
| 9 | Will it rain in Washington DC on Sep 23, 2026? | 99.0% | +43.0 pts | 96 | $6,864 |
| 10 | Heart of the Beast Rotten Tomatoes score? | 99.0% | +35.0 pts | 96 | $19,012 |
Top Polymarket Movers
Esports markets experienced sharp directional moves. In League of Legends, Solary vs ZSK rose 30.9 points to 99.9%, and Galions vs Saigon Warriors gained 32.5 points to 99.9%. Conversely, Counter-Strike saw QUAZAR vs Misa Esports drop 69.5 points to 0.1%, while fnatic vs Phantom increased 33.5 points to 95.5%.
Tennis and geopolitical markets also shifted significantly. Murphy Cassone vs Clement Tabur moved 50.5 points higher to 99.9%. However, other tennis matches like Ankara (Solana Sierra) and Plovdiv (Oriol Roca Batalla) fell over 59.0 points. The Saudi Oil Pipeline restart probability dropped 31.5 points to 56.5%.
| # | Market | Probability | 24h move | Significance | Volume |
|---|---|---|---|---|---|
| 1 | LoL: Solary vs ZSK (BO1) - World Star Challengers Invitational Group D | 99.9% | +30.9 pts | 100 | $358K |
| 2 | St. Tropez: Murphy Cassone vs Clement Tabur | 99.9% | +50.5 pts | 100 | $549K |
| 3 | Counter-Strike: fnatic vs Phantom (BO3) - Stake Pulse Beat II Group C | 95.5% | +33.5 pts | 100 | $183K |
| 4 | Counter-Strike: QUAZAR vs Misa Esports (BO3) - European Pro League Series 9 Playoffs | 0.1% | −69.5 pts | 100 | $279K |
| 5 | LoL: Galions vs Saigon Warriors (BO1) - World Star Challengers Invitational Group D | 99.9% | +32.5 pts | 100 | $170K |
| 6 | Hangzhou Open: Aleksandar Vukic vs Kyrian Jacquet | 27.5% | −20.0 pts | 100 | $349K |
| 7 | Ankara: Solana Sierra vs Deniz Dilek | 0.1% | −83.5 pts | 100 | $161K |
| 8 | Saudi Oil Pipeline (East-West) restarts by September 30? | 56.5% | −31.5 pts | 99 | $97,989 |
| 9 | Plovdiv 4: Oriol Roca Batalla vs Calvin Hemery | 0.1% | −59.5 pts | 97 | $111K |
| 10 | LoL: ZSK vs Galions (BO1) - World Star Challengers Invitational Group D | 0.1% | −25.9 pts | 97 | $224K |
Largest Trades
On Kalshi, large institutional-style blocks targeted the 2027 Congressional control outlook. Multiple NO positions on 'House Control Republican AND Senate Control Republican' were traded, including sizes of $541K, $181K, and $57K at 91%. Smaller but notable YES bets appeared in Florida Governorship ($79K) and House Democrats ($45K+).
Polymarket volume concentrated in MLB games. A $1.36M NO trade on Cincinnati Reds vs Atlanta Braves stood out, followed by $549K NO on Tampa Bay Rays vs New York Yankees. Other significant trades included $382K on the Reds/Braves matchup and $247K on the Rays/Yankees game.
| Venue | Market | Side | Notional | Price | Time (ET) | 5m move |
|---|---|---|---|---|---|---|
| Polymarket | Cincinnati Reds vs. Atlanta Braves | NO | $1.36M | 71% | 16:45 ET | 0.0 pts |
| Polymarket | Tampa Bay Rays vs. New York Yankees | NO | $549K | 60% | 12:35 ET | 0.0 pts |
| Kalshi | Will House Control be Republican AND Senate Control be Republican for Feb 2027? | NO | $541K | 91% | 10:04 ET | −0.4 pts |
| Polymarket | Cincinnati Reds vs. Atlanta Braves | NO | $382K | 70% | 16:45 ET | 0.0 pts |
| Polymarket | Tampa Bay Rays vs. New York Yankees | NO | $247K | 59% | 12:35 ET | 0.0 pts |
| Polymarket | Cincinnati Reds vs. Atlanta Braves | NO | $226K | 67% | 16:34 ET | −3.0 pts |
| Kalshi | Will House Control be Republican AND Senate Control be Republican for Feb 2027? | NO | $181K | 91% | 10:04 ET | −0.4 pts |
| Kalshi | Will the Republican party win the governorship in Florida | YES | $79,000 | 79% | 12:35 ET | 0.0 pts |
| Kalshi | Will House Control be Republican AND Senate Control be Republican for Feb 2027? | NO | $57,063 | 91% | 10:04 ET | −0.4 pts |
| Kalshi | Will Republicans win the House in 2026? | NO | $45,550 | 91% | 23:50 ET | −0.1 pts |
Where Kalshi and Polymarket Disagree
Divergence is most prominent in the 2028 Democratic Presidential nomination markets. Kalshi prices Alexandria Ocasio-Cortez at 15.5% compared to Polymarket's 18.3%, a 2.8-point gap. Jon Ossoff shows a smaller 0.8-point difference, with Kalshi at 16.5% versus Polymarket at 15.7%.
Other candidates show narrower spreads. Michelle Obama has a 1.6-point gap (Kalshi 1.9% vs Polymarket 0.3%), while Josh Shapiro differs by 1.4 points (Kalshi 4.7% vs Polymarket 6.0%). These variances highlight differing liquidity or sentiment between the platforms for specific political figures.
| Contract | Grade | Kalshi | Polymarket | Gap |
|---|---|---|---|---|
| Will Alexandria Ocasio-Cortez be the Democratic Presidential nominee in 2028 | B | 15.5% | 18.3% | 2.8 pts |
| Will Michelle Obama be the Democratic Presidential nominee in 2028 | B | 1.9% | 0.3% | 1.6 pts |
| Will Josh Shapiro be the Democratic Presidential nominee in 2028 | B | 4.7% | 6.0% | 1.4 pts |
| Will Andy Beshear be the Democratic Presidential nominee in 2028 | B | 3.6% | 2.5% | 1.1 pts |
| Will Mark Kelly be the Democratic Presidential nominee in 2028 | B | 4.0% | 2.9% | 1.0 pts |
| Will Rahm Emanuel be the Democratic Presidential nominee in 2028 | B | 2.9% | 2.1% | 0.8 pts |
| Will Jon Ossoff be the Democratic Presidential nominee in 2028 | B | 16.5% | 15.7% | 0.8 pts |
| Will Kamala Harris be the Democratic Presidential nominee in 2028 | B | 7.2% | 6.5% | 0.8 pts |
| Will J.B. Pritzker be the Democratic Presidential nominee in 2028 | B | 1.9% | 1.2% | 0.7 pts |
| Will Ro Khanna be the Democratic Presidential nominee in 2028 | B | 1.8% | 1.3% | 0.6 pts |
Cross-Market Opportunities
Price discrepancies exist between venues for several 2028 Democratic nomination markets. For example, Kalshi lists AOC at 15.5% while Polymarket lists her at 18.3%, creating a 2.8-point spread. Similarly, Michelle Obama trades at 1.9% on Kalshi versus 0.3% on Polymarket, a 1.6-point difference.
Additional gaps include Josh Shapiro (1.4 points), Andy Beshear (1.1 points), and Mark Kelly (1.0 point). Traders evaluating these differences must consider fees, settlement rules, and execution risk, as these theoretical edges do not guarantee profit.
Five Markets to Watch Today
Keep an eye on the Philadelphia rain market, which saw the largest single-day move (+86.0 pts) and remains highly active.
Monitor the Trump 'Antifa' commentary market, which spiked 84.0 points to near-certainty, reflecting rapid information incorporation.
Watch the AOC 2028 nomination market for convergence between Kalshi (15.5%) and Polymarket (18.3%) pricing.
Track the Cincinnati Reds vs Atlanta Braves game, which featured the largest single trade of the session at $1.36M.
- Will it rain in Philadelphia on Sep 23, 2026? Most significant Kalshi move
- LoL: Solary vs ZSK (BO1) - World Star Challengers Invitational Group D Most significant Polymarket move
- Will Alexandria Ocasio-Cortez be the Democratic Presidential nominee in 2028 Largest cross-venue disagreement
- Cincinnati Reds vs. Atlanta Braves Largest trade of the session
- Will Trump say "Antifa" before Oct 1, 2026? Runner-up significant move
Methodology and Timestamp
Snapshot frozen Sep 23, 08:04 ET ET (2026-09-23 12:04 UTC). Evidence hash d42570a1ba7b3065.