The Prediction Markets

What will the peak RONI value be during the 2026-27 El Niño season?

Closes
Aug 15, 2027, in 10 months
Traded
$252K
Venues
Polymarket, Kalshi
Prices updated
just now
Share

What the markets expect

Over 2.5 68.5%

Next is 2.5°C to 2.9°C at 49%. The venues differ most on Under 1.5 (Polymarket 0.1%, Kalshi 2%), a 1.9-point gap.

Odds by venue

Consensus blends each venue’s last price, weighted by how much has traded there. Best Yes price is the cheapest ask across venues, and the payout is what a winning $100 stake returns before fees. Open a row for each venue’s contract name, bid and ask, and how closely their rules match.

2 of 10 prices are live from the exchange feeds; the rest come from our regular price polls. Ages are as of when this page was built.

  • Polymarket
  • Kalshi
Over 2.5
68.5%
Polymarket 68.5%polled, 37s agoBest Yes 69¢ on Polymarket, $100 pays $145 (1.45x)
Polymarket
Contract
Over 2.5
Last price
68.5%
As of
Polled just now
Buy Yes
69¢
Sell Yes
68¢
$100 on Yes pays
$145 (1.45x)
Volume
$52K
Trade this on Polymarket
2.5°C to 2.9°C
49%
Kalshi 49%polled, 37s agoBest Yes 56¢ on Kalshi, $100 pays $179 (1.79x)
Kalshi
Contract
2.5°C to 2.9°C
Last price
49%
As of
Polled just now
Buy Yes
56¢
Sell Yes
49¢
$100 on Yes pays
$179 (1.79x)
Volume
$44K
Trade this on Kalshi
At least 3.0°C
40%
Kalshi 40%polled, 37s agoBest Yes 41¢ on Kalshi, $100 pays $244 (2.44x)
Kalshi
Contract
At least 3.0°C
Last price
40%
As of
Polled just now
Buy Yes
41¢
Sell Yes
40¢
$100 on Yes pays
$244 (2.44x)
Volume
$51K
Trade this on Kalshi
2.25–2.5
30.5%
Polymarket 30.5%polled, 37s agoBest Yes 31¢ on Polymarket, $100 pays $323 (3.23x)
Polymarket
Contract
2.25–2.5
Last price
30.5%
As of
Polled just now
Buy Yes
31¢
Sell Yes
30¢
$100 on Yes pays
$323 (3.23x)
Volume
$54K
Trade this on Polymarket
2.0°C to 2.4°C
6%
Kalshi 6%polled, 37s agoBest Yes 6¢ on Kalshi, $100 pays $1,667 (16.7x)
Kalshi
Contract
2.0°C to 2.4°C
Last price
6%
As of
Polled just now
Buy Yes
6¢
Sell Yes
4¢
$100 on Yes pays
$1,667 (16.7x)
Volume
$29K
Trade this on Kalshi
1.5°C to 1.9°C
2%
Kalshi 2%polled, 37s agoBest Yes 2¢ on Kalshi, $100 pays $5,000 (50.0x)
Kalshi
Contract
1.5°C to 1.9°C
Last price
2%
As of
Polled just now
Buy Yes
2¢
Sell Yes
1¢
$100 on Yes pays
$5,000 (50.0x)
Volume
$6K
Trade this on Kalshi
2.0–2.25
1.5%
Polymarket 1.5%polled, 37s agoBest Yes 2.2¢ on Polymarket, $100 pays $4,545 (45.5x)
Polymarket
Contract
2.0–2.25
Last price
1.5%
As of
Polled just now
Buy Yes
2.2¢
Sell Yes
0.7¢
$100 on Yes pays
$4,545 (45.5x)
Volume
$7K
Trade this on Polymarket
Under 1.5Arb
1.4%
Polymarket 0.1%live, 22s agoKalshi 2%live, just nowBest Yes 0.1¢ on Polymarket, $100 pays $100,000 (1000x)
Polymarket
Contract
Under 1.5
Price
0.1%
As of
Live feed, just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$2K
Trade this on Polymarket
Kalshi
Contract
Below 1.5°C
Price
2%
As of
Live feed, just now
Buy Yes
2¢
Sell Yes
1¢
$100 on Yes pays
$5,000 (50.0x)
Volume
$4K
Trade this on Kalshi
Partial parity

Payoffs match in ordinary outcomes; see the rule differences below the table.

Buying on Polymarket at 0.1¢ and selling on Kalshi at 1¢ nets 90 bps before fees.

1.5–2.0
0.1%
Polymarket 0.1%polled, 37s agoBest Yes 0.1¢ on Polymarket, $100 pays $100,000 (1000x)
Polymarket
Contract
1.5–2.0
Last price
0.1%
As of
Polled just now
Buy Yes
0.1¢
Sell Yes
—
$100 on Yes pays
$100,000 (1000x)
Volume
$5K
Trade this on Polymarket

Possible arbitrage before fees: buy Under 1.5 on Polymarket at 0.1¢, sell on Kalshi at 1¢ (90 bps). Check the rules below before trading. See all live spreads

Mostly the same bet: 3 differences

Where they differ

  • Seasons counted differ: Kalshi MJJ 2026 through MAM 2027; Polymarket ASO 2026 through DJF 2026-27.
  • Bracket edges differ above 1.5; only identical ranges ('Below 1.5') are linked.
  • Trading closes at different times: Apr 1, 2027, 3:59 AM UTC on Polymarket and Aug 15, 2027, 2:00 PM UTC on Kalshi.
Polymarket
Polymarket resolves via:
UMA optimistic oracle, source: cpc.ncep.noaa.gov
Kalshi
Kalshi resolves via:
Kalshi (CFTC-regulated exchange), source: NOAA Climate Prediction Center
Show full rule comparison
  • Seasons counted differ: Kalshi MJJ 2026 through MAM 2027; Polymarket ASO 2026 through DJF 2026-27.
  • Bracket edges differ above 1.5; only identical ranges ('Below 1.5') are linked.
  • Trading closes Apr 1, 2027, 3:59 AM UTC on Polymarket and Aug 15, 2027, 2:00 PM UTC on Kalshi.

Summarized from each venue’s published rules; the venue’s own rules page is the final word.

How the odds have moved

The top 3 outcomes on both venues, with the consensus between them. Hover for exact values.

  • Over 2.5
  • 2.5°C to 2.9°C
  • At least 3.0°C

Order books

Each venue’s resting orders for the selected outcome’s Yes contract, side by side. Top of book streams live; depth refreshes every 15 seconds.

Polymarket

Open on Polymarket ↗

Top of book

Connecting
Best bid
—
Spread
—
Best ask
—

Waiting for the first live quote…

Depth · top 8 levels

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Recent trades

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Kalshi

Kalshi doesn’t list Over 2.5 for this event.

What your stake buys

Enter a stake to see where it buys the most after fees, using each venue’s live order book.

$
Buy

Loading both order books…

Buys at the asks resting now (taker orders), cheapest after fees first, from order-book snapshots up to 15 seconds old. Fees: Kalshi 0.07 × price × (1 − price) per share, rounded up to the cent; Polymarket 0.05 × price × (1 − price) per share (other / general rate). Fee calculator. Estimates only, not advice.

About this market

Live prediction market odds for "What will the peak RONI value be during the 2026-27 El Niño season?". Over 2.5 leads at 68.5%. Next is 2.5°C to 2.9°C at 49%. $252K has traded across 9 outcomes on Kalshi and Polymarket. The market is expected to resolve by Aug 15, 2027.

Questions

What does the consensus price mean?

It is the price of a Yes contract that pays $1 if the outcome happens. A 14¢ price means traders put the chance near 14%. Where two venues list the same outcome, we blend their last prices, weighting the venue with more trading volume more heavily (neither counts for less than a quarter). When only one outcome can win, each venue’s prices add up to a little over 100% (its margin); the fair chance removes that margin so the outcomes add up to exactly 100%.

How is the payout worked out?

A Yes contract pays $1 if it wins, so at the best ask a $100 stake buys 100 ÷ ask contracts. At 18¢ that is about 555 contracts, paying $556 (5.56x) if Yes happens. Venue fees and price slippage on larger orders are not included.

Why do the venues show different prices?

Each venue has its own traders, fees and order book. Contracts can also settle on slightly different terms, which is why each row lists how closely the rules match.

Is a price gap an arbitrage?

Only when you can buy Yes on one venue below what someone pays for Yes on the other, after fees, and both contracts settle the same way. We show the executable bid and ask so you can check.

How fresh are these prices?

Venue prices refresh every few minutes, and the order book and live quotes stream continuously. Each venue’s card shows when we last observed it.

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