How Miami Temperature Contracts Settle, and Why the Venue Picks the Record

A Miami temperature contract in one paragraph

A Miami temperature contract asks which band a measured reading will fall in, and it is settled by a record published after the day is over, never by the forecast that came before it. Each observation day carries a high row and a low row. Every row is a set of two-degree bands with an open cell at each end, so on any one venue exactly one band pays and the others expire at nothing. The part a reader most often skips is the part that decides the money: Kalshi and Polymarket do not read the same record. One takes the day's figure from the National Weather Service's daily climate report for Miami, and the other works it out from the routine hourly observations at Miami International Airport, in tenths of a degree Celsius.

How a Miami contract settles, step by step

1. Start with the venue, because the venue chooses the record. Kalshi's KXHIGHMIA and KXLOWTMIA contracts pay on the maximum or minimum temperature "recorded at Miami (CLIMIA)" according to The Weather Company. CLIMIA is the National Weather Service's climate summary for Miami, issued by its Miami office, with the report covering a whole day published early the next morning. Polymarket's Miami events pay on the highest or lowest temperature in the routine METAR reports for Miami Intl Airport, station KMIA, as the Aviation Weather Center publishes them.

2. Know what precision each record carries. The climate report prints the day's maximum and minimum in whole degrees Fahrenheit, and Kalshi's terms settle on the full precision the source reports. Polymarket reads the hourly temperature remark at the end of each routine report, a T followed by eight digits that gives the temperature in tenths of a degree Celsius, converts it with °F = °C × 9/5 + 32 and rounds to the nearest whole degree, rounding an exact half up. The routine KMIA report at 1:53 p.m. Eastern on November 6, 2026 carried the remark T02890189: 28.9°C, which is 84.02°F and counts as 84°F.

3. Read which reports count. Polymarket counts every routine report on the observation date and disregards any report whose line begins with SPECI, which the rule defines as a special observation, so a peak that appears only in a special report does not enter its Miami contract. The day is the station's local date, daylight saving included. The climate report prints the time of each extreme in local standard time, marked LST.

4. Read the band edges for that date, not from memory. Kalshi's Miami bands are inclusive at both ends and move from one date to the next: the November 5, 2026 high row was cut on even numbers, 82° to 83° and 84° to 85°, while the November 7 row was cut on odd ones, from 83° to 84° up to 89° to 90°, with 82° or below and 91° or above at the ends. Polymarket's November 7 high row ran from 77°F or below to 96°F or higher, cut on even numbers. On November 5, 2026 the climate report recorded a Miami maximum of 85°F at 3:08 p.m., and Kalshi's 84° to 85° band was the one that settled Yes.

5. Keep the clocks straight. Kalshi's November 7, 2026 Miami contracts are set to close at 1 a.m. Eastern on November 8, and its terms count only the first official report not marked preliminary. Polymarket resolves at the first routine report of the following day or at 11:59 p.m. Eastern that day, whichever comes first, and reads the observations as its source shows them at that point.

6. Read the fallback before you need it. If Kalshi finds a material error in the first non-preliminary report, it can hold expiration until corrected data appears, and if no reliable figure arrives in time every band settles at the last fair price the exchange sets. Polymarket turns to Weather Underground's daily observations if the Aviation Weather Center has published nothing by the deadline, resolves to the lowest band if neither has data, and can keep a market open for up to seven days while a clearly erroneous reading is corrected.

Where Florida readers stand

A thermometer at Miami International Airport settles a band; it does not settle whether a person in Florida may trade one. That turns on the state's record of filings and orders about each exchange, which is listed with its dates on the legal status page, and this guide forms no view of its own about any venue. This guide is not legal advice and not financial advice.

Common misreadings

The forecast high decides the day. No forecast appears in any of these rules. An outlook moves the prices while the day is being priced, and the contract then pays on what the record shows.

Both venues read the same number. They read different records with different precision: a once-a-day climate summary in whole degrees Fahrenheit on one side, hourly airport reports in tenths of a degree Celsius on the other. Near a band edge, the two can settle the same afternoon in neighboring bands without either being wrong about its own contract.

Final on the provider's page means final. Kalshi's own rules say a status of Final on its data provider's page is a convenience and no assurance that the data is free of error, and its material-error hold still applies.

A Miami contract is a Florida reading. It is a reading for one place. Nothing taken in Tampa, Orlando or Tallahassee enters a Miami band, and Miami is the only Florida city on the weather board.

An odd-number band on one date lines up with the next. Kalshi moves its edges between dates, so a band that read 84° to 85° on one day can read 83° to 84° two days later. Compare bands only within one date and one venue.

Related guides and markets

The live Miami rows, with the high, the low and the monthly rain ladder, are on the Miami weather page, and the weather vertical is at the Florida weather hub. A Florida contract that settles on a published statistic rather than an instrument is the guide to how the Florida gas price contract settles, and a field where exactly one entry pays across a whole season is the guide to how NFC Championship odds work.

This guide is not legal advice and not financial advice. It explains which record settles a Miami temperature contract and names no band, no side and no exchange to use.