# Consecutive days of average temperature in Oklahoma City above 90°F - week of Aug 18, 2026

Week of Aug 18 – Aug 24, 2026

Updated: August 22, 2026

Category: Climate and Weather

Tags: Heatwaves

HTML: /markets/climate-and-weather/heatwaves/consecutive-days-of-average-temperature-in-oklahoma-city-above-90-f-week-of-aug-18-2026/

## Short Answer

**Key takeaway.** Both the **model** and the **market** expect 2+ consecutive days of average temperature in Oklahoma City above 90°F during the week of August 18, 2026, with no compelling evidence of mispricing.

## Key Claims (August 2026)

**- - Two or three consecutive days of 90°F+ average temperature are confirmed by observational data up to August 21, 2026.** - Streaks of four or more days are not met; observational data confirms the three-day streak ended.

## Executive Verdict

**Key takeaway.** **Market** prices at **2.0%** (2c), above **model**'s **0.0%**, as definitive data confirmed only a three-day streak.

### Who Wins and Why

| Outcome | Market | Model | Why |
| --- | --- | --- | --- |
| 4+ consecutive days | 2.0% | 0.0% | Observational data confirms the streak of average temperatures strictly above 90°F ended after three days. |
| 3+ consecutive days | 66.0% | 87.9% | Observational data confirms a three-day streak of average temperatures strictly above 90°F was met. |
| 5+ consecutive days | 2.0% | 0.0% | Observational data confirms the streak of average temperatures strictly above 90°F ended after three days. |

## Model vs Market

| Outcome | Market Probability | Octagon Model Probability |
| --- | --- | --- |
| 4+ consecutive days | 2.0% | 0.0% |
| 3+ consecutive days | 66.0% | 87.9% |
| 5+ consecutive days | 2.0% | 0.0% |
| 6+ consecutive days | 1.0% | 0.0% |
| 2+ consecutive days | 99.0% | 100.0% |

- Expiration: August 24, 2026

## Market Behavior & Price Dynamics

This market experienced a short-lived but extreme price movement. The contract began and ended at a price of 2.0%, establishing this level as a firm floor. The price remained flat until spiking to a peak of 90.0% on August 20. This sharp increase reflected news of a persistent high-pressure ridge that had already produced a 28-day streak of temperatures above 90°F as of August 14. Traders priced in a high probability that the entrenched weather system would sustain the heatwave through the required resolution date of August 24.

The market's conviction collapsed on August 21, when the price fell 88.0 percentage points back to 2.0%. This reversal was driven by confirmed weather data that forecast an end to the heatwave on August 22, breaking the streak. The 90.0% level acted as a clear resistance point, representing peak market optimism just before the new information emerged. The total volume of 23,598 contracts suggests significant activity during this period of volatility. Overall, the price action indicates a market that was highly reactive to near-term meteorological reports, with sentiment shifting from near-certainty to near-impossibility in a single day based on a definitive forecast change.

## Significant Price Movements

### Outcome: 3+ consecutive days

#### 📉 August 22, 2026: 26.0pp drop

Price decreased from 92.0% to 66.0%

**What happened:** The 26.0 percentage point drop in the prediction market on August 22, 2026, was primarily driven by the definitive end of an average temperature streak in Oklahoma City. On August 22, the average temperature dropped significantly to 79°F, formally concluding the four-day streak of average temperatures above 90°F that had occurred from August 18 through August 21 [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC). Although the market's "3+ consecutive days" outcome was technically met by August 20 [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC), the abrupt termination of the ongoing above-90°F average temperature trend likely prompted a re-evaluation of market probabilities. Social media activity was irrelevant to this price movement, as no related information was found.

### Outcome: 6+ consecutive days

#### 📉 August 21, 2026: 89.0pp drop

Price decreased from 90.0% to 1.0%

**What happened:** The primary driver of the 89.0 percentage point price drop on August 21, 2026, was the confirmed weather data indicating an end to the prolonged heatwave. While Oklahoma City's daily maximum temperature was 101°F on August 21, the forecast or confirmed observation for August 22, 2026, showed a significant drop to a high of 81°F, effectively breaking any consecutive streak of 90°F+ temperatures [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OKC&product=CF6&site=NWS&version=1)[[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC). This abrupt end meant that achieving "6+ consecutive days" of above 90°F temperatures within the week of August 18 became impossible, leading to the sharp market adjustment. No social media activity from key figures or viral narratives related to this price movement were identified in the provided research, indicating it was irrelevant to this specific market event.

### Outcome: 5+ consecutive days

#### 📈 August 19, 2026: 36.0pp spike

Price increased from 2.0% to 38.0%

**What happened:** The primary driver for the market spike was the concurrent release of traditional news and official weather announcements on August 19, 2026, confirming an intense and prolonged heatwave in Oklahoma City. An Extreme Heat Warning was issued for OKC, with the heat index expected to hit 109°F, while local news reported continued record heat after the city experienced 109°F on August 18 [[^]](https://www.oklahoman.com/story/weather/2026/08/19/extreme-heat-warning-issued-for-okc-as-heat-index-expected-to-hit-109/91369455007/)[[^]](https://www.koco.com/article/record-high-temperature-in-oklahoma-heat-hot/73474485)[[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=0&issuedby=OKC&product=CLI&site=NWS&version=7). This information, solidifying that daily maximum temperatures were consistently above 90°F for at least 20 consecutive days, likely led to the sharp increase in the prediction market [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=0&issuedby=OKC&product=CLI&site=NWS&version=7). Social media activity cannot be assessed as a driver, as no information was provided in the research.

## Contract Snapshot

This Kalshi market resolves "YES" if Oklahoma City experiences at least the specified number of consecutive days with an average temperature above 90°F during the week of August 18, 2026. A "NO" resolution occurs if this condition is not met. The market is scheduled to resolve by August 24, 2026.

## Market Discussion

During the week of August 18, 2026, Oklahoma City experienced four consecutive days of average temperatures above 90°F, specifically from August 18 to August 21, with daily averages recorded as 91°F, 93°F, 93°F, and 90°F respectively [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CLI&site=NWS)[[^]](https://tgftp.nws.noaa.gov/data/climate/daily/ok/oklahoma_city.txt). This intense heatwave, which also saw daily maximum temperatures consistently exceeding 90°F, generated significant public interest and active speculation in prediction markets regarding daily maximum temperatures [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://www.news9.com/weather/oklahoma-city-weather-forecast)[[^]](https://www.coinrithm.com/en/prediction-markets/kalshi/kxhightokc-26aug20)[[^]](https://www.coinrithm.com/en/prediction-markets/kalshi/kxhightokc-26aug21)[[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC).

## Market Data

| Contract | Yes Bid | Yes Ask | Last Price | Volume | Open Interest |
| --- | --- | --- | --- | --- | --- |
| 2+ consecutive days | 99% | 100% | 99% | $2,425 | $2,425 |
| 3+ consecutive days | 16% | 57% | 66% | $15,341.66 | $8,367.18 |
| 4+ consecutive days | 1% | 2% | 2% | $23,598.47 | $16,733.39 |
| 5+ consecutive days | 1% | 2% | 2% | $12,432.26 | $7,854.42 |
| 6+ consecutive days | 0% | 1% | 1% | $5,710.78 | $4,395.66 |

## How did the long-range forecasts from the GFS and European (ECMWF) models differ in their predictions for Oklahoma City's weather during the week of August 18, 2026?

Forecast Period | Week of August 18, 2026 (for Oklahoma City) [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=44)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=42)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=38) |
GFS Model Outlook | Potential shift towards cooler temperatures [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26) |
ECMWF Model Outlook | Sustained extreme heat [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26) |

**Long-range forecasts diverged for Oklahoma City during August 2026**

Long-range forecasts diverged for Oklahoma City during August 2026. For the week of August 18, 2026, the GFS and ECMWF models presented significantly different long-range predictions for Oklahoma City's weather, particularly concerning projected atmospheric patterns and associated temperature outcomes [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=44)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=42)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=38). The GFS **model** indicated a potential shift towards cooler temperatures, contrasting with the ECMWF **model**, which suggested the persistence of extreme heat [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26).

Specific atmospheric patterns differed significantly between the models. As of August 16, 2026, the GFS **model** anticipated a pattern shift involving ridge amplification and trough development that could have led to cooler conditions [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26). Conversely, the ECMWF **model** maintained a forecast of stronger upper-level ridging over the Southern Plains, indicating continued extreme heat [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26). For the mid-week of August 18, 2026, the GFS **model** depicted a trough entering the Plains, whereas the ECMWF **model**'s medium-range projections kept Oklahoma City under the influence of a large upper-level ridge [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=44)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=42)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=38).

## What do climatological records from the Oklahoma Climatological Survey indicate about the typical duration of heatwaves that begin in July and extend into late August?

Heat Wave Span | Mid-summer into late August [[^]](https://www.weather.gov/oun/climate-okc-heatwave)[[^]](http://www.ou.edu/ocs/oklahoma-climate/weather-timeline.html)[[^]](https://en.m.wikipedia.org/wiki/Climate_of_Oklahoma_City) |
OCS Heat Wave Definition | Abnormal heat for at least two consecutive days [[^]](https://southernclimate.org/hazards/oklahoma-heat-extremes/)[[^]](https://en.m.wikipedia.org/wiki/Climate_of_Oklahoma_City) |
Oklahoma City Peak Temp (Aug 2026) | 107°F [[^]](https://www.duncanbanner.com/news/ocs-july-begins-with-destructive-winds-ends-in-a-heat-wave/article_9caa9925-1215-4324-8479-14d6a7bff6e1.html)[[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN) |

**Oklahoma heat waves frequently begin in July and persist through late August**

Oklahoma heat waves frequently begin in July and persist through late August. Climatological records from the Oklahoma Climatological Survey (OCS) indicate that heat waves in Oklahoma typically begin in mid-summer and extend into late August [[^]](https://www.weather.gov/oun/climate-okc-heatwave)[[^]](http://www.ou.edu/ocs/oklahoma-climate/weather-timeline.html)[[^]](https://en.m.wikipedia.org/wiki/Climate_of_Oklahoma_City). The OCS defines a heat wave as a period of abnormal heat lasting a minimum of two consecutive days during the hot season, determined by local conditions and specific temperature thresholds [[^]](https://southernclimate.org/hazards/oklahoma-heat-extremes/)[[^]](https://en.m.wikipedia.org/wiki/Climate_of_Oklahoma_City). Historically, significant heat waves, including those in 1936, 1980, and 2011, consistently saw triple-digit temperatures that continued well into the latter half of August [[^]](https://www.weather.gov/oun/climate-okc-heatwave)[[^]](http://www.ou.edu/ocs/oklahoma-climate/weather-timeline.html)[[^]](https://en.m.wikipedia.org/wiki/Climate_of_Oklahoma_City).

Extreme high temperatures are common, but weekly averages rarely exceed 90°F. While extreme heat events can produce multiple consecutive days with temperatures at or exceeding 100°F, daily average temperatures (calculated from daily high and low) rarely remain above 90°F for an entire week [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN). For instance, during August 18–24, 2026, Oklahoma City recorded high temperatures reaching 107°F, which is consistent with historical patterns of hot, dry summer conditions in the state [[^]](https://www.duncanbanner.com/news/ocs-july-begins-with-destructive-winds-ends-in-a-heat-wave/article_9caa9925-1215-4324-8479-14d6a7bff6e1.html)[[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN). During this specific week, Oklahoma City's daily average temperatures ranged between 87°F and 93°F [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN). Generally, Oklahoma's summertime average high temperatures in July and August fall within the low-to-mid 90s [[^]](https://www.weather.gov/tsa/climo_clisummer).

## Which specific forecast model updates on August 20-21, 2026, provided the earliest signals of the heat dome's collapse over Oklahoma City?

Initial Model Signal Date | August 20-21, 2026 [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26)[[^]](https://forecast.weather.gov/product.php?format=TXT&glossary=0&issuedby=OUN&product=AFD&site=NWS&version=20) |
Expected Cooling Trend | 90s for August 22-23, then 80s [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&highlight=off&issuedby=OUN&product=AFD&site=NWS&version=4)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=0&issuedby=OUN&product=SFT&site=NWS&version=21) |
Heat Dome Status on August 21 | Persistent threat, triple-digit highs [[^]](https://weather.com/2026/08/21/forecast/regional/south-heat-wave-records-forecast)[[^]](https://okcfox.com/news/local/drought-worsens-but-showers-are-in-the-forecast) |

**Early forecast models indicated a potential heat dome collapse**

Early forecast models indicated a potential heat dome collapse. Around August 20-21, 2026, medium-range forecast models, specifically the NAM and GFS, first signaled a shift in the upper-level pattern [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26)[[^]](https://forecast.weather.gov/product.php?format=TXT&glossary=0&issuedby=OUN&product=AFD&site=NWS&version=20)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&highlight=off&issuedby=OUN&product=AFD&site=NWS&version=4)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=0&issuedby=OUN&product=SFT&site=NWS&version=21). This shift involved the amplification of an upper-level ridge in the West and the development of a trough from the Great Lakes toward the Mid-Mississippi Valley, which was expected to establish a northwest flow over the Plains [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26)[[^]](https://forecast.weather.gov/product.php?format=TXT&glossary=0&issuedby=OUN&product=AFD&site=NWS&version=20)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&highlight=off&issuedby=OUN&product=AFD&site=NWS&version=4)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=0&issuedby=OUN&product=SFT&site=NWS&version=21). Forecast discussions and tabular state forecasts from these dates explicitly projected a cooling trend, anticipating temperatures in the 90s for the weekend of August 22-23, followed by a drop into the 80s [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26)[[^]](https://forecast.weather.gov/product.php?format=TXT&glossary=0&issuedby=OUN&product=AFD&site=NWS&version=20)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&highlight=off&issuedby=OUN&product=AFD&site=NWS&version=4)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=0&issuedby=OUN&product=SFT&site=NWS&version=21). This projected temperature decrease was interpreted as a signal for the intense heat dome's collapse.

Heat dome persistence challenged early cooling trend forecasts. Despite initial indications, the National Weather Service (NWS) noted on August 21, 2026, that the National Blend of Models (NBM) was not yet fully capturing the magnitude of the anticipated cooling, often predicting higher temperatures than expected [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=26). Consequently, as of August 21, 2026, the heat dome remained a significant threat for Oklahoma City, with continued forecasts for triple-digit highs [[^]](https://weather.com/2026/08/21/forecast/regional/south-heat-wave-records-forecast)[[^]](https://okcfox.com/news/local/drought-worsens-but-showers-are-in-the-forecast). This reinforced that the heat dome had not definitively collapsed by that date [[^]](https://weather.com/2026/08/21/forecast/regional/south-heat-wave-records-forecast)[[^]](https://okcfox.com/news/local/drought-worsens-but-showers-are-in-the-forecast).

## What real-time observational data from the National Weather Service or Oklahoma Mesonet could have been used to verify the imminent breakdown of the heatwave on August 21, 2026?

Data observation frequency | every 5 minutes [[^]](https://www.mesonet.org/about/data-descriptions/daily-summaries)[[^]](https://www.mesonet.org/) |
Oklahoma City high temperature on August 21, 2026 | 101°F [[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC) |
Oklahoma City high temperature on August 22, 2026 | 81°F [[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC) |

**The Oklahoma Mesonet provides high-resolution data to verify heatwave breakdowns swiftly**

The Oklahoma Mesonet provides high-resolution data to verify heatwave breakdowns swiftly. This network offers real-time observational data, including 5-minute air temperature, humidity, and wind patterns from stations located across all 77 Oklahoma counties [[^]](https://www.mesonet.org/about/data-descriptions/daily-summaries)[[^]](https://www.mesonet.org/). This extensive, high-resolution data would have been instrumental in verifying the imminent breakdown of the August 21, 2026, heatwave. By analyzing shifts in the daily maximum heat index or trends in average temperature, the Mesonet could confirm a heatwave's dissipation before daily summaries were finalized [[^]](https://www.mesonet.org/about/data-descriptions/daily-summaries)[[^]](https://www.oklahoman.com/story/weather/2026/08/20/stubborn-high-pressure-keeps-oklahoma-locked-in-triple-digit-heat/91375386007/).

Changes in wind, temperature, and humidity indicated the heatwave's end. The August 2026 heatwave was driven by a persistent subtropical high-pressure ridge, and its breakdown would have been observable through corresponding shifts in regional wind patterns, temperatures, and humidity recorded by the Mesonet network [[^]](https://www.oklahoman.com/story/weather/2026/08/20/stubborn-high-pressure-keeps-oklahoma-locked-in-triple-digit-heat/91375386007/). Specifically, the Mesonet would have captured the sharp drop in temperature and a shift in wind patterns, such as to an easterly component, associated with the cold frontal passage that ended the heatwave on August 21-22, 2026 [[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC)[[^]](https://forecast.weather.gov/showsigwx.php?firewxzone=OKZ025&local_place1=Choctaw+OK&product1=Extreme+Heat+Warning&warncounty=OKC109&warnzone=OKZ025). For instance, Oklahoma City recorded a high temperature of 101°F on August 21, 2026, which significantly dropped to 81°F on August 22, clearly indicating a major breakdown of the heatwave observable by regional networks such as the Oklahoma Mesonet [[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC)[[^]](https://forecast.weather.gov/showsigwx.php?firewxzone=OKZ025&local_place1=Choctaw+OK&product1=Extreme+Heat+Warning&warncounty=OKC109&warnzone=OKZ025)[[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=oun&product=AFD&site=NWS&version=1).

## How did the atmospheric drivers of the August 2026 heatwave compare to those observed during Oklahoma's record-setting heatwave in the summer of 2011?

Common Driver | Persistent upper-level high-pressure ridges (heat domes) over Southern Plains [[^]](https://www.oklahoman.com/story/weather/2026/08/20/stubborn-high-pressure-keeps-oklahoma-locked-in-triple-digit-heat/91375386007/)[[^]](https://www.dtnpf.com/agriculture/web/ag/news/article/2026/08/21/southern-plains-heat-wave-continues)[[^]](http://amp.greatfallstribune.com/story/news/2011/08/31/wednesday-marks-the-end-of-the-hottest-climatological-summer-on-record-for-oklahoma/61138233007/)[[^]](https://www.weather.gov/tsa/weather-event_2011drought)[[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://preview.weather.gov/oun/events-2011summary) |
2026 Heatwave Characteristics | Short-term eastward expansion of a Southwestern ridge and intermittent frontal boundary interactions [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://preview.weather.gov/oun/events-2011summary)[[^]](https://www.weather.gov/tsa/weather-event_2011drought) |
2011 Heatwave Characteristics | Multi-month persistence tied to a La Niña phase [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://preview.weather.gov/oun/events-2011summary)[[^]](https://www.weather.gov/tsa/weather-event_2011drought) |

**Both the August 2026 and the record-setting 2011 Oklahoma heatwaves were driven by a common atmospheric phenomenon**

Both the August 2026 and the record-setting 2011 Oklahoma heatwaves were driven by a common atmospheric phenomenon. These events were primarily caused by strong, persistent upper-level high-pressure ridges, commonly known as heat domes, that settled over the Southern Plains [[^]](https://www.oklahoman.com/story/weather/2026/08/20/stubborn-high-pressure-keeps-oklahoma-locked-in-triple-digit-heat/91375386007/)[[^]](https://www.dtnpf.com/agriculture/web/ag/news/article/2026/08/21/southern-plains-heat-wave-continues)[[^]](http://amp.greatfallstribune.com/story/news/2011/08/31/wednesday-marks-the-end-of-the-hottest-climatological-summer-on-record-for-oklahoma/61138233007/)[[^]](https://www.weather.gov/tsa/weather-event_2011drought)[[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://preview.weather.gov/oun/events-2011summary). However, these two significant heatwaves differed markedly in their broader atmospheric influences and overall duration. The 2011 event was notable for its multi-month persistence, which was strongly linked to a prevailing La Niña phase, whereas the 2026 event involved a more short-term eastward expansion of the ridge and interactions with frontal boundaries [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://preview.weather.gov/oun/events-2011summary)[[^]](https://www.weather.gov/tsa/weather-event_2011drought).

The two heatwaves differed significantly in their broader influences and duration. The August 2026 Oklahoma heatwave resulted from a persistent, nearly immobile subtropical high-pressure ridge positioned over the Southern Plains, effectively blocking cold fronts and trapping hot, dry air for weeks [[^]](https://www.oklahoman.com/story/weather/2026/08/20/stubborn-high-pressure-keeps-oklahoma-locked-in-triple-digit-heat/91375386007/)[[^]](https://www.dtnpf.com/agriculture/web/ag/news/article/2026/08/21/southern-plains-heat-wave-continues). This event's primary driver was an upper-level high-pressure heat dome expanding eastward from the Southwestern U.S., further reinforced by a Pacific trough on the West Coast [[^]](https://forecast.weather.gov/product.php?format=CI&glossary=1&issuedby=OUN&product=AFD&site=NWS&version=8)[[^]](https://forecast.weather.gov/product.php?issuedby=OUN&product=AFD&site=NWS). This 2026 heatwave was specifically characterized by this short-term eastward expansion of a Southwestern ridge and intermittent frontal boundary interactions [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://preview.weather.gov/oun/events-2011summary)[[^]](https://www.weather.gov/tsa/weather-event_2011drought), which led to sustained triple-digit temperatures and a "ground heating" feedback where dry soil radiates heat at night, elevating overnight temperatures [[^]](https://www.oklahoman.com/story/weather/2026/08/20/stubborn-high-pressure-keeps-oklahoma-locked-in-triple-digit-heat/91375386007/)[[^]](https://www.duncanbanner.com/news/ocs-july-begins-with-destructive-winds-ends-in-a-heat-wave/article_9caa9925-1215-4324-8479-14d6a7bff6e1.html)[[^]](https://www.oklahomafarmreport.com/2026/08/19/oklahoma-endures-hottest-day-since-2022-as-extreme-heat-continues-across-the-state/)[[^]](https://www.kswo.com/2026/08/21/dangerous-heat-continues-drought-conditions-worsen-820-pm/). In contrast, the record-setting 2011 Oklahoma heatwave was driven by a strong, persistent upper-level high-pressure ridge [[^]](http://amp.greatfallstribune.com/story/news/2011/08/31/wednesday-marks-the-end-of-the-hottest-climatological-summer-on-record-for-oklahoma/61138233007/), but it was intensely amplified by pre-existing severe, multi-year drought conditions. Feedback loops during the 2011 event meant that solar energy heated the dry ground directly, rather than being absorbed by evaporating soil moisture [[^]](http://amp.greatfallstribune.com/story/news/2011/08/31/wednesday-marks-the-end-of-the-hottest-climatological-summer-on-record-for-oklahoma/61138233007/)[[^]](https://www.sciencedaily.com/releases/2011/08/110831210108.htm)[[^]](https://ams.confex.com/ams/94Annual/webprogram/Paper237402.html). This historic heatwave was profoundly influenced by a persistent La Niña pattern, which anchored a large-scale high-pressure ridge over the Southern Plains for months. This resulted in sinking air that inhibited clouds and rainfall while worsening extreme soil moisture deficits [[^]](https://www.weather.gov/tsa/weather-event_2011drought)[[^]](https://www.weather.gov/sjt/climate-heatdrought2011), defining its multi-month persistence [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://preview.weather.gov/oun/events-2011summary)[[^]](https://www.weather.gov/tsa/weather-event_2011drought).

## What Could Change the Odds

**Oklahoma City experienced extreme heat throughout the week of August 18–24, 2026, driven by a persistent subtropical high-pressure ridge [[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC)[[^]](https://www.oklahoman.com/story/weather/2026/08/20/stubborn-high-pressure-keeps-oklahoma-locked-in-triple-digit-heat/91375386007/).** By August 22, 2026, the city had recorded 26 days of temperatures at or above 100°F in 2026 [[^]](https://www.oklahoman.com/story/weather/2026/08/20/stubborn-high-pressure-keeps-oklahoma-locked-in-triple-digit-heat/91375386007/).

**During this period, daily high temperatures reached 109°F on August 18, 104°F on August 19, and 107°F on August 20 [[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN)[[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC).** Average daily temperatures exceeded 90°F from August 18 (91°F) through August 20 (93°F), with the streak ending on August 21, 2026, at 90°F [[^]](https://mesonet.agron.iastate.edu/sites/hist.phtml?network=OK_ASOS&station=OKC)[[^]](https://forecast.weather.gov/product.php?issuedby=OKC&product=CF6&site=OUN). The National Weather Service issued Extreme Heat Warnings for the Oklahoma City area, forecasting heat index values as high as 111°F [[^]](https://www.oklahoman.com/story/weather/2026/08/19/extreme-heat-warning-issued-for-okc-as-heat-index-expected-to-hit-109/91369455007/)[[^]](https://www.koco.com/article/weekend-forecast-storms-possible-parts-of-oklahoma-heat-wave-continues/73499523)[[^]](https://forecast.weather.gov/wwamap/wwatxtget.php?cwa=TSA&wwa=extreme+heat+warning).

**Prediction markets, including Kalshi, actively traded on daily maximum temperature outcomes for Oklahoma City during the week [[^]](https://www.coinrithm.com/en/prediction-markets/kalshi/kxhightokc-26aug20)[[^]](https://predictmarketcap.com/events/will-the-maximum-temperature-be-114-on-aug-19-2026-aug-20-2026)[[^]](https://www.coinrithm.com/en/prediction-markets/kalshi/kxhightokc-26aug21).** Localized weather patterns, frontal boundaries, and the persisting high-pressure ridges served as catalysts, influencing bullish and bearish positions among traders [[^]](https://www.coinrithm.com/en/prediction-markets/kalshi/kxhightokc-26aug20)[[^]](https://predictmarketcap.com/events/will-the-maximum-temperature-be-114-on-aug-19-2026-aug-20-2026)[[^]](https://www.coinrithm.com/en/prediction-markets/kalshi/kxhightokc-26aug21).

## Key Dates & Catalysts

- **Expiration:** August 26, 2026
- **Closes:** August 24, 2026

## Decision-Flipping Events

- Oklahoma City experienced extreme heat throughout the week of August 18–24, 2026, driven by a persistent subtropical high-pressure ridge [^] [^] .
- By August 22, 2026, the city had recorded 26 days of temperatures at or above 100°F in 2026 [^] .
- During this period, daily high temperatures reached 109°F on August 18, 104°F on August 19, and 107°F on August 20 [^] [^] .
- Average daily temperatures exceeded 90°F from August 18 (91°F) through August 20 (93°F), with the streak ending on August 21, 2026, at 90°F [^] [^] .

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## Historical Resolutions

No historical resolution data available for this series.

## Disclaimer

This content is for informational and educational purposes only and does not constitute financial, investment, legal, or trading advice.
Prediction markets involve risk of loss. Past performance does not guarantee future results.
We are not affiliated with Kalshi or any prediction market platform. Market data may be delayed or incomplete.

### Data Sources & Model Transparency

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**Freshness:** Analysis is generated periodically and may not reflect the latest developments. Verify critical information from primary sources.

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