Global Temperature Markets 2026

Nine daily temperature boards across two exchanges, and the two venues are now a day apart. Polymarket settles its city boards at noon UTC, which passed this morning, so its ladders have rolled to September 20 while Kalshi's Los Angeles and Miami books still price today's high and settle tomorrow afternoon. The pairing below reads as a one-day spread, not a mirror.

Los Angeles is where the pattern is clearest. Kalshi's ladder puts 77° or below at 51% and 78° to 79° at 40%, yet the busiest rung on the board is 80° to 81° at 13%, which took $22,278, with 82° to 83° at 2% taking another $15,220. That is $37,498—52% of a $72,457 day—on two rungs worth fifteen cents between them.

It is not a Los Angeles quirk. Tokyo put $1,869 into 19°C or below at two-tenths of a cent, Seoul put $2,410 into a 5% rung, Shanghai $2,771 into a 3% rung, and Beijing put $4,489—41% of its whole board—into 26°C at 20%, the third-likeliest outcome. Bitcoin and ether show the same shape today.

Left is Kalshi's book on today's Los Angeles high, settling at 3pm ET tomorrow. Right is Polymarket's board for tomorrow's high, settling at 8am ET tomorrow—seven hours earlier and a day later. Same city, two clocks, and today the two are not asking about the same afternoon at all.

Left is Kalshi's 77° or below at 51%, the closest thing to a genuine coin flip on any board here, on 10,367 contracts. Right is Polymarket's 76-77°F at 54% for tomorrow. The two favourites land within a degree of each other despite pricing different days, which is the strongest evidence on this page that both books are reading the same forecast.

Hong Kong is the deepest Polymarket board at $19,430, and it is close to binary: 33°C at 51% and 32°C at 45% take 96% of the weight between them, with $6,539 on the leader. Busan is thinner at $7,330 and reads 29°C at 48% against 28°C at 37%—and the 37% rung, not the favourite, is the one that took the most money.

Tokyo prices 24°C at 50% with 23°C at 31% on a $14,104 day. The oddity is 19°C or below, priced at 0.2%, which took $1,869—the board's third-busiest rung. Seoul is tighter at the top, 27°C at 55% against 26°C at 30%, but its second-busiest contract is 25°C at 5% with $2,410 against the favourite's $2,952.

Shanghai is a genuine two-way board: 28°C at 50% and 29°C at 40%, with $3,661 and $3,570 behind them. Beijing is the day's clearest example of the pattern—28°C leads at 30%, but 26°C at 20% took $4,489, 41% of the board. Miami, Kalshi's other US book, rolled to today's high: 86° to 87° at 39% against 84° to 85° at 28%.

Watch the Miami board settling this afternoon. Its September 18 predecessor traded $217,763 into settlement with 89° to 90° printing at 99%, and every quote midpoint on it reads exactly 0.50—there is no two-sided market left, only an answer waiting for the official reading. That is what a resolved-but-unsettled Kalshi weather book looks like, and it is worth recognising before treating a 50-cent midpoint as a real price.

Watch whether the cheap-rung flow persists. Five of nine boards put their largest ticket somewhere other than the favourite today, and bitcoin and ether did the same thing at 38% and 52% of their day volume. Three unrelated complexes in one session is a behaviour rather than a coincidence.

Watch the Los Angeles coin flip. At 51% it is the only rung on this page with both depth and genuine uncertainty.