Ten facts that decide how every Kalshi daily-high market pays, each checked against the live data and the rulebook on October 19, 2026. Pick a city below for its station, its window today, how it has settled and when its high happens.
Since the August 14, 2026 events these markets settle on The Weather Company, not the NWS report many guides still name. What changed, and what didn't · Yesterday's results
The ten facts in full, each with its source, are below.
01
The rules name an NWS climate-report code (CLINYC, CLIMDW, ...), and that code names one weather station. Chicago settles on Midway (KMDW), not O'Hare. Houston settles on Hobby (KHOU), not Bush Intercontinental. Austin settles on Austin-Bergstrom (KAUS), not Camp Mabry.
Read the station from the rules, never from the series title: Louisville's series (KXHIGHTSDF) is titled "SATX", but its rules name CLISDF, Louisville's station.
Source: Kalshi contract terms (GLOBALTEMPERATURE); NWS climate report header, e.g. Central Park (CLINYC)
02
From the August 14, 2026 events on, the rules say "according to The Weather Company". Before that they named the National Weather Service's Daily Climate Report.
Across every settled day since the switch, Kalshi's value matched The Weather Company in 1,541 of 1,541 checks and the NWS report in 1,539 of 1,540. Only the first non-preliminary report counts; revisions after expiration don't.
Source: Kalshi contract terms (GLOBALTEMPERATURE); The Weather Company, weather.com/kalshi; Almanac's cross-check of 1,541 settled days
03
The NWS climate day is midnight to midnight local standard time, and it doesn't move for daylight saving. In summer that makes it 1:00 AM to 1:00 AM on the local clock, so a warm reading at 12:30 AM daylight time still counts toward the day before.
Kalshi's trading close matches it: 00:00 standard time after the day, which is 1:00 AM daylight time, not the 11:59 PM that the market's close-condition text says. Phoenix keeps standard time all year, so there the window is midnight to midnight on the clock.
The window for any city and date
Source: NWS observation FAQ; Kalshi's close time on all 1,589 events since Aug 14, 2026
04
A between bracket such as "65° to 66°" wins on 65 or 66. A bottom tail with a cap of 65 wins only below 65, so it is "64° or below". A top tail with a floor of 72 wins only above 72, so it is "73° or above".
The tickers don't tell you which way a tail points ("T65" and "T72" are both T). Almanac reads the direction from Kalshi's strike type and shows the whole degrees each bracket wins on.
Source: Kalshi contract terms (GLOBALTEMPERATURE); Almanac's check of 47,614 settled markets
05
The value compared with the brackets is the whole-degree high the source publishes. If the sensor peaks at 71.6°F and the report says 72, the 71-72 bracket wins and the "above 72" tail does not.
Your own unrounded reading or forecast doesn't count; only the published integer does.
Source: Kalshi contract terms ("full precision reported by the Source Agency")
06
Kalshi sends prices as exact dollar strings ("0.5400" is 54¢). When no one is bidding, the bid shows as 0.0000; when no one is offering, the ask shows as 1.0000. Neither is a price, so Almanac shows them as "—".
The best asks across one day's six brackets add up to more than $1 (1.08 in one sampled New York event) and the bids to a little over $1, so neither column reads straight across as a probability.
Source: Kalshi API documentation (market fields); Live market data, checked Oct 19, 2026
07
One contract at 54¢ pays a 2¢ fee; 100 at 54¢ pay $1.74. Cheap contracts carry the most: one contract at 5¢ still pays 1¢, which is 20% of its price.
So the price at which an order breaks even is (price x contracts + fee) / contracts, not the price alone.
Kalshi weather fees, the break-even price and the rounding trap
Source: Kalshi Fee Schedule (effective Feb 5, 2026); Each series' fee type ("quadratic", multiplier 1)
08
Two days trade at once: today and tomorrow. Trading closes at 00:00 standard time after the day, and the settlement usually posts around 7 AM local time (a median of 6.2 hours after close, 7.2 hours for the slowest tenth).
Settlements can be held: three events since August 14 took more than a day, the longest 7.4 days. A few settled as fractions (one Miami day paid $0.01 and $0.99), so a payout isn't always exactly $0 or $1.
Source: Kalshi contract terms (GLOBALTEMPERATURE); Open, close and settlement times of 1,589 events
09
Weather stations keep whole degrees Fahrenheit and report them as tenths of a degree Celsius, so round(C x 9/5 + 32) recovers the exact reading. The rounded °C in the report's body is not precise enough.
The peak can fall between hourly reports: on October 18, 2026 Central Park's hourly readings topped out at 56°F, but the 6-hour maximum and the official high were 57. The official high can still differ from every report, and occasionally comes in lower when the NWS discards a bad reading.
Decode a METAR's exact reading
Source: NWS ASOS program; 394 reports checked across 10 stations
10
At Los Angeles airport the ECMWF ensemble mean has run about 8°F hot; at Austin, HRRR has run about 3°F cold. A raw model number read on its own can mislead by several brackets.
Almanac shows every model raw and corrected for its own record at that station, with how many days that correction rests on.
Source: Open-Meteo previous model runs; Almanac's 90-day calibration of 12 models at 24 stations
Also
The NWS issues a preliminary climate report in the late afternoon and the full-day report shortly after midnight standard time. Settlement uses the first non-preliminary value. On July 4, 2025 Central Park's 4 PM climate report said 82°F; the final report after midnight said 83, because the high came at 4:04 PM.
The same daily question on Polymarket, settled its own way. Read city by city on Kalshi vs Polymarket, and its world cities on the world board.
P1
New York settles on LaGuardia (KLGA), not Central Park; Chicago on O'Hare (KORD), not Midway; Dallas on Love Field (KDAL), not DFW; Denver on Buckley Space Force Base (KBKF), not Denver International. The other US cities share Kalshi's station.
Its world cities each name an airport too, like London City (EGLC). Read the station from each market's rules: a market's text wins over any list, Almanac's included.
Source: Polymarket's public market data and each event's rules
P2
In its US cities the answer is the highest temperature among the day's routine hourly readings, in whole degrees Fahrenheit, as the station publishes them. Kalshi's official daily high can be higher than any one of them, so the two can settle a degree or more apart.
In its world cities it's the highest routine reading in whole degrees Celsius: the report's tenths, where it has them, rounded to the nearest degree, a half up.
Source: Polymarket's public market data and each event's rules
P3
A share of the range the day's reading lands in pays $1. In the US the ranges start on even degrees, like 64-65°F; abroad each answer is one degree, like 18°C.
Source: Polymarket's public market data and each event's rules
P4
Kalshi counts local standard time instead, so in summer its day runs 1 AM to 1 AM and the two exchanges' days are an hour apart: a reading at 12:30 AM counts toward the new day on Polymarket and the day before on Kalshi.
Source: Polymarket's public market data and each event's rules
P5
That's at most $1.25 per 100 shares, at 50¢. Kalshi's is 0.07 × contracts × price × (1 − price), rounded up to the cent per order.
Source: Polymarket documentation: fees
Almanac shows information and tools. It never says what to buy or sell and never places an order.