Prediction Markets Morning — 2026-09-20
What moved overnight, where Kalshi and Polymarket disagree, and the trades and conversation around them.
What moved overnight, where Kalshi and Polymarket disagree, and the trades and conversation around them.
The Overnight Picture
Will it rain in Columbus on Sep 20, 2026? moved +57.0 pts to 99.0%, the most significant liquidity-adjusted move on Kalshi. Will the price of Ethereum be above $2,600 on September 20? moved −76.9 pts to 9.6%, the most significant liquidity-adjusted move on Polymarket. No matched contracts show gaps of 5 pts or more.
Top Kalshi Movers
Will it rain in Columbus on Sep 20, 2026? (+57.0 pts to 99.0%); Will it rain in Milwaukee on Sep 20, 2026? (+47.0 pts to 99.0%); Will it rain in Philadelphia on Sep 20, 2026? (+29.0 pts to 99.0%) lead the ranking by movement significance, which weights the size of each move by volume, liquidity and spread.
| # | Market | Probability | 24h move | Significance | Volume |
|---|---|---|---|---|---|
| 1 | Will it rain in Columbus on Sep 20, 2026? | 99.0% | +57.0 pts | 98 | $4,934 |
| 2 | Will it rain in Milwaukee on Sep 20, 2026? | 99.0% | +47.0 pts | 97 | $5,234 |
| 3 | Will it rain in Philadelphia on Sep 20, 2026? | 99.0% | +29.0 pts | 90 | $9,413 |
| 4 | Will it rain in New York City on Sep 20, 2026? | 99.0% | +24.0 pts | 86 | $10,998 |
| 5 | Will it rain in Boston on Sep 20, 2026? | 99.0% | +24.0 pts | 86 | $9,770 |
| 6 | Will it rain in Chicago on Sep 20, 2026? | 99.0% | +24.0 pts | 82 | $4,709 |
| 7 | Will over 3.5 goals be scored? | 88.5% | +37.5 pts | 78 | $27,939 |
| 8 | Will it rain in Denver between Sep 19 and Sep 20, 2026? | 99.0% | +19.0 pts | 76 | $6,715 |
| 9 | Tencent market share this week? | 95.5% | +79.5 pts | 68 | $26,091 |
| 10 | Will it rain in Providence on Sep 20, 2026? | 99.0% | +16.0 pts | 66 | $3,920 |
Top Polymarket Movers
Will the price of Ethereum be above $2,600 on September 20? (−76.9 pts to 9.6%); LoL: EDward Gaming Youth Team vs T1 Academy (BO1) - World Star Challengers Invitational Group A (+85.0 pts to 99.9%); LoL: DN SOOPers Challengers vs T1 Academy (BO1) - World Star Challengers Invitational Group A (−30.9 pts to 0.1%) lead the ranking by movement significance, which weights the size of each move by volume, liquidity and spread.
| # | Market | Probability | 24h move | Significance | Volume |
|---|---|---|---|---|---|
| 1 | Will the price of Ethereum be above $2,600 on September 20? | 9.6% | −76.9 pts | 100 | $39,814 |
| 2 | LoL: EDward Gaming Youth Team vs T1 Academy (BO1) - World Star Challengers Invitational Group A | 99.9% | +85.0 pts | 100 | $258K |
| 3 | LoL: DN SOOPers Challengers vs T1 Academy (BO1) - World Star Challengers Invitational Group A | 0.1% | −30.9 pts | 100 | $452K |
| 4 | Will Bitcoin reach $82,000 September 14-20? | 8.6% | −49.5 pts | 100 | $61,762 |
| 5 | Bitcoin Up or Down on September 20? | 2.8% | −45.8 pts | 100 | $116K |
| 6 | Ethereum Up or Down on September 20? | 2.5% | −47.5 pts | 100 | $49,170 |
| 7 | Gamba Ōsaka vs. Vissel Kōbe: O/U 2.5 | 0.1% | −49.0 pts | 99 | $35,773 |
| 8 | Will Nicolás Maduro be the leader of Venezuela end of 2026? | 50.5% | −33.7 pts | 99 | $192K |
| 9 | Davis Cup: Felix Auger-Aliassime vs. Arthur Rinderknech | 99.9% | +30.9 pts | 99 | $110K |
| 10 | Will Delcy Rodríguez be the leader of Venezuela end of 2026? | 42.0% | +29.5 pts | 99 | $209K |
Largest Trades
The largest recorded execution was $262K on Polymarket in Bengals vs. Texans, followed by $245K in Will Nottingham Forest FC win on 2026-09-19?. Size and price impact are measured separately; the tables show the price five minutes after each trade.
| Venue | Market | Side | Notional | Price | Time (ET) | 5m move |
|---|---|---|---|---|---|---|
| Polymarket | Bengals vs. Texans | NO | $262K | 58% | 16:15 ET | −1.0 pts |
| Polymarket | Will Nottingham Forest FC win on 2026-09-19? | YES | $245K | 60% | 12:15 ET | 0.0 pts |
| Polymarket | James Madison vs. San Diego State | YES | $181K | 93% | 00:12 ET | +1.0 pts |
| Polymarket | Steelers vs. Patriots | YES | $165K | 32% | 07:42 ET | — |
| Polymarket | UFC 331: Alexandre Pantoja vs. Joshua Van (Flyweight, Main Card) | NO | $148K | 59% | 21:05 ET | — |
| Kalshi | Will Democrats win the House in 2026? | YES | $90,000 | 90% | 10:33 ET | 0.0 pts |
| Kalshi | Clemson wins | YES | $82,500 | 66% | 17:39 ET | +39.5 pts |
| Kalshi | Aston Villa wins | YES | $71,492 | 99% | 09:19 ET | 0.0 pts |
| Kalshi | Green Bay wins by over 3.5 points? | YES | $62,675 | 47% | 22:03 ET | 0.0 pts |
| Kalshi | Will LSU win the LSU vs Ole Miss college football game? | YES | $55,573 | 48% | 22:34 ET | +10.0 pts |
Where Kalshi and Polymarket Disagree
Will Alexandria Ocasio-Cortez be the Democratic Presidential nominee in 2028 shows the widest disagreement: Kalshi 15.5% versus Polymarket 18.2%, a 2.7 pt gap. Gaps can reflect rule differences, fees and venue access as well as differing views.
| Contract | Grade | Kalshi | Polymarket | Gap |
|---|---|---|---|---|
| Will Alexandria Ocasio-Cortez be the Democratic Presidential nominee in 2028 | B | 15.5% | 18.2% | 2.7 pts |
| Will Michelle Obama be the Democratic Presidential nominee in 2028 | B | 2.2% | 0.3% | 1.9 pts |
| Will Gavin Newsom be the Democratic Presidential nominee in 2028 | B | 13.5% | 15.3% | 1.8 pts |
| Will Kamala Harris be the Democratic Presidential nominee in 2028 | B | 8.1% | 9.7% | 1.6 pts |
| Will Josh Shapiro be the Democratic Presidential nominee in 2028 | B | 4.7% | 6.1% | 1.4 pts |
| Will Mark Kelly be the Democratic Presidential nominee in 2028 | B | 4.1% | 2.9% | 1.2 pts |
| Will Rahm Emanuel be the Democratic Presidential nominee in 2028 | B | 3.1% | 1.9% | 1.1 pts |
| Will Andy Beshear be the Democratic Presidential nominee in 2028 | B | 3.1% | 2.5% | 0.7 pts |
| Will J.B. Pritzker be the Democratic Presidential nominee in 2028 | B | 1.9% | 1.3% | 0.7 pts |
| Will James Talarico be the Democratic Presidential nominee in 2028 | B | 1.8% | 2.4% | 0.6 pts |
Cross-Market Opportunities
No Grade A pair currently shows a positive theoretical edge from executable prices.
Five Markets to Watch Today
Each pick below is selected by a different signal: movement significance, cross-venue disagreement and trade size.
- Will it rain in Columbus on Sep 20, 2026? Most significant Kalshi move
- Will the price of Ethereum be above $2,600 on September 20? Most significant Polymarket move
- Will Alexandria Ocasio-Cortez be the Democratic Presidential nominee in 2028 Largest cross-venue disagreement
- Bengals vs. Texans Largest trade of the session
- Will it rain in Milwaukee on Sep 20, 2026? Runner-up significant move
Methodology and Timestamp
Tables are computed from Kalshi and Polymarket public market data at the snapshot time. Movement is in percentage points; significance, impact and evidence scores are described on the methodology page.
Snapshot frozen Sep 20, 08:03 ET ET (2026-09-20 12:03 UTC). Evidence hash a74b83de9cdaf205.