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OpenEnergy · Heating demandWeather index future · simulation

Chicago heating degree days · Week 48 · Nov 23 - Nov 29

Heating degree days at KORD · 7 local days, 2026-11-23 to 2026-11-29 · trading closes 11-29 06:00 (15 d)

Market index
101.2°C-days
Long 54.7¢ · Short 45.3¢ per share
Model fair
126.3 ± 16.8
priced 23 min ago
Edge
+25.2
fair minus market
Volume
363
11 traders
Open interest
443 / 274
long / short shares
30 · long pays 0long pays 1 · 160
Market 101.2Model fair 126.3
Listed at 95.7 · quoted by a market maker, no order book · one share moves 0.0077 sUSDT per index point

Real-asset futures that follow this index

simulated prices

Each contract below is a commodity price index the demo simulates: 100 on the day it was listed, moved by this contract's HDD and by a simulated market factor. Weather-implied is the price at the index this market is trading at now; when it differs from the asset's own market price, simulated spread traders trade the two against each other.

ContractMarket priceWeather-implied
NGAS-KORD-26W48Natural gas106.03long 55¢104.60

How the index builds, day by day

ForecastBeyond the forecast

Each bar is one local day's contribution to the index. Days with a final NWS climate report count as they stand (shown as final record); a day whose report is not out yet uses the METAR figure and is marked not final; the rest are the model's estimate, with a whisker one standard deviation either way.

0132511-2311-2411-2511-2611-2711-2811-29
Day-by-day table
DaySourceHighLowHDDRunning total
Mon, Nov 23Forecast30.2°F23.5°F20.8 ± 3.320.8
Tue, Nov 24Forecast32.4°F23.0°F20.4 ± 3.541.2
Wed, Nov 25Forecast35.6°F25.7°F18.8 ± 3.760.0
Thu, Nov 26Forecast41.7°F27.9°F16.4 ± 4.076.4
Fri, Nov 27Forecast47.5°F32.9°F13.4 ± 4.289.9
Sat, Nov 28Beyond the forecast35.4°F27.7°F18.2 ± 4.5108.1
Sun, Nov 29Beyond the forecast35.4°F27.7°F18.2 ± 4.5126.4

Market index path

one step per trade · dashed line: model fair now
85.8110.0134.1

Recent trades

TimeTradeSharesAmountAvg price
11-13 17:50Buy shortpair37.1216.6344.8¢
11-13 16:50Buy shortpair19.558.6244.1¢
11-13 16:50Buy long109.5160.0054.8¢
11-13 14:50Buy shortpair11.115.1646.4¢
11-13 13:50Buy long114.7760.0052.3¢
11-13 10:50Buy long77.9038.8549.9¢
11-13 05:50Buy short31.1015.7750.7¢
11-13 03:50Buy short85.5342.1349.3¢
11-12 19:50Buy short18.358.8048.0¢
11-12 18:50Buy short71.5933.5346.8¢
11-12 13:50Buy long114.0060.0052.6¢
11-12 08:50Buy long27.1913.8350.9¢

A trade marked pair is one leg of a simulated spread trade: the other leg is in a real-asset contract that follows this index.

Settlement

KORD is a US station, so this contract settles on the NWS daily climate report (CLI) of each of its 7 days: the index is the sum built from the high and low the National Weather Service prints. The local forecast office issues each report after local midnight, normally within one to three hours, and the contract settles one day after the last report is issued - about 12-01 08:00. A corrected report replaces the earlier one and the day runs again from it. If any day has no final report three days after the period ends, the contract is void and every position is refunded at cost. NWS CLI Watch ↗

Contract specification

Symbol
HDD-KORD-26W48
Index
Heating degree days (HDD), in °C-days
Formula
max(0, 18 - (high + low) / 2), summed over the period
Station
KORD · Chicago
Period
Week 48 · Nov 23 - Nov 29 · 7 local days, 2026-11-23 to 2026-11-29
Band
30 to 160
Payoff
Long: (index - 30) / 130 sUSDT per share, held to 0..1. Short: 1 minus that.
Point value
0.0077 sUSDT per share per index point
Trading closes
2026-11-29 06:00 UTC
Settles
One day after the NWS climate report for the last day is issued
Settlement source
The NWS daily climate report (CLI) of each day, as carried by the Weather Market oracle
Hedges
Energy - Natural gas, Heating oil, District heat (the exposure it hedges; this contract settles on the index)
Trade HDD-KORD-26W48

Long gains if HDD finishes above the level you pay for.

Virtual sUSDT only. No monetary value.

Rules in short
  • Long gains when the index finishes higher, short when it finishes lower. A long and a short share together always pay 1 sUSDT.
  • Outside the band 30 to 160 the contract pays as if the index had finished on the edge.
  • You pay in full when you buy. What you paid is the most you can lose: no margin, no liquidation.
  • You can sell back to the market maker at any time before trading closes, when the last day of the period begins.
  • A US station: the index is built from the high and low in the NWS daily climate report of each day, and the contract settles a day after the last of those reports is issued. Void, with every position refunded at cost, if any day has no final report three days after the period ends.
Full rules →