Short Answer

Hurricane Norbert is not expected to reach Category 1 or above. National Hurricane Center advisories forecast the tropical storm to degenerate into a remnant low by September 15, 2026, and dissipate without reaching hurricane intensity, an outcome the market prices at 7.0%.

1. Market Behavior & Drivers

The dominant price move in this market was a 77.0 percentage point drop on September 12, 2026, driven by a shift in the meteorological outlook for Tropical Storm Norbert. National Hurricane Center forecasts on that day indicated Norbert was expected to become a hurricane. When the storm failed to intensify as predicted, the market probability of it reaching hurricane status collapsed from 85.0% to 8.0%.
The market's earlier climb was tied to the storm's initial development. A 52.0 percentage point spike on September 10 coincided with the official formation of Tropical Storm Norbert. No specific drivers were identified for the smaller spikes on September 9 and September 11. As of September 13, Norbert remains a Tropical Storm, and the market price reflects a low probability of it reaching hurricane strength.
  • Norbert is not expected to reach hurricane intensity, forecast to dissipate by September 16, 2026.
  • National Hurricane Center forecasts degeneration into a remnant low by September 15, 2026.

Who Wins and Why

Outcome Market Model Why
Category 1 or above 7.0% 2.4% The National Hurricane Center forecasts Tropical Storm Norbert to dissipate before reaching hurricane intensity.
Category 2 or above 5.0% 1.7% The National Hurricane Center forecasts Tropical Storm Norbert to dissipate before reaching hurricane intensity.
Category 3 or above 0.0% 0.0% The National Hurricane Center forecasts Tropical Storm Norbert to dissipate before reaching hurricane intensity.
Category 4 or above 0.0% 0.0% The National Hurricane Center forecasts Tropical Storm Norbert to dissipate before reaching hurricane intensity.
Category 5 or above 0.0% 0.0% The National Hurricane Center forecasts Tropical Storm Norbert to dissipate before reaching hurricane intensity.

Current Context

Tropical Storm Norbert has not reached hurricane status as of September 13, 2026. While the National Hurricane Center's September 12, 2026, forecasts indicated Norbert was expected to become a hurricane within 24 hours, it remains a Tropical Storm [1][2][3][4][5]. The most recent advisory (Advisory 14) reports maximum sustained winds for Tropical Storm Norbert at 45–50 mph [2][3].
Norbert is expected to weaken significantly and dissipate by mid-week. Forecasts indicate the system will degenerate into a remnant low by Tuesday, September 15, 2026, and fully dissipate by Wednesday, September 16, 2026 [2][3]. Norbert is located well east of Hawaii and poses no land threat, with no coastal watches or warnings currently in effect [2][3].
Sources (5)
  1. 1Tropical Storm Norbert Graphics - National Hurricane Center - NOAAnhc.noaa.gov
  2. 2Tropical Storm Norbert Public Advisory Number 14 - je.st - Tropical Storm Norbert Public Advisory Number 14je.st
  3. 3Summary for Tropical Storm Norbert (EP4/EP142026) - je.st - Summary for Tropical Storm Norbert (EP4/EP142026)je.st
  4. 4Tropical Storm Norbert Tracker | Weather Undergroundwunderground.com
  5. 5Tropical Storm Norbert Forecast Discussionnhc.noaa.gov

2. Price Chart

Historical Price (Probability)

Outcome probability
Date

3. Significant Price Movements

Notable price changes detected in the chart, along with research into what caused each movement.

📉 September 12, 2026: 77.0pp drop

Price decreased from 85.0% to 8.0%

Outcome: Category 1 or above

What happened: The primary driver of the 77.0 percentage point drop in the "Hurricane Norbert category?" prediction market on September 12, 2026, was the evolving meteorological outlook for Tropical Storm Norbert. Although the National Hurricane Center forecasted on early September 12, 2026, that Norbert would become a hurricane within 24 hours [1], it consistently remained a tropical storm [2][3][4][5] and was subsequently forecast to weaken into a remnant low by September 15, 2026 [5][6]. This shift in outlook, from potential intensification to expected weakening, signaled that Norbert was unlikely to achieve Category 1 hurricane status, causing the market to price in the lower probability of that outcome [2][3][4][5][6]. No social media activity was identified as a driver; therefore, social media was irrelevant to this price movement.

📈 September 11, 2026: 17.0pp spike

Price increased from 69.0% to 86.0%

Outcome: Category 1 or above

What happened: No specific social media activity, traditional news announcements, or market structure factors are identified in the provided web research that would explain the 17.0 percentage point spike on September 11, 2026. The available information primarily indicates that as of September 13, 2026, Norbert is classified as a tropical storm with maximum sustained winds near 50 mph, and is expected to weaken [5][6][7]. While some early forecasts suggested potential intensification, no specific event on September 11, 2026, is detailed to coincide with this particular market movement [6]. Based solely on the provided data, social media was irrelevant as a primary driver or accelerant.

📈 September 10, 2026: 52.0pp spike

Price increased from 17.0% to 69.0%

Outcome: Category 1 or above

What happened: The primary driver for the 52.0 percentage point spike in the "Hurricane Norbert category?" prediction market on September 10, 2026, was the official formation of Tropical Storm Norbert earlier that day [6]. Despite initial reports on September 10, 2026, stating it was expected to weaken [6], the market likely reacted to the storm's formal designation by pricing in the potential for intensification to Category 1 or above. This initial market optimism for the newly formed storm's potential appears to have been present, as a September 12, 2026, forecast indicated Norbert was expected to become a hurricane within 24 hours [1]. Social media activity was not identified as a primary driver or contributing accelerant for this market movement.

📈 September 09, 2026: 10.0pp spike

Price increased from 2.0% to 12.0%

Outcome: Category 1 or above

What happened: The research indicates that social media was not a primary driver for the 10.0 percentage point price spike in the "Hurricane Norbert category?" market on September 9, 2026. On this date, Norbert was a tropical depression, not a hurricane, and there is no evidence of social media activity specifically related to it reaching Category 1 [5][8][9]. While significant weather events like record rainfall in Japan and storms in Switzerland occurred on September 9, 2026, they were unrelated to Hurricane Norbert [10][11][8][9]. Thus, social media was irrelevant, and the primary driver for this market movement is not identified in the provided information.
Sources (11)
  1. 1Tropical Storm Norbert Forecast Discussionnhc.noaa.gov
  2. 2Tropical Storm Norbert Forecast Advisory Number 14 - je.st - Tropical Storm Norbert Forecast Advisory Number 14je.st
  3. 3Tropical Storm Norbert Public Advisory Number 14 - je.st - Tropical Storm Norbert Public Advisory Number 14je.st
  4. 4Summary for Tropical Storm Norbert (EP4/EP142026) - je.st - Summary for Tropical Storm Norbert (EP4/EP142026)je.st
  5. 5Tropical Storm Norbert Tracker | Weather Undergroundwunderground.com
  6. 6Tropical Storm Norbert churns in the Pacific, expected to weaken...foxweather.com
  7. 7Tropical Storm Norbert Graphics - National Hurricane Center - NOAAnhc.noaa.gov
  8. 8Thousands of lightning strikes batter Switzerland overnightswissobserver.ch
  9. 9Nagoya Shatters 136-Year Rainfall Record as Linear Rain Band Overwhelms City Drainstechtimes.com
  10. 10Hail storms on Sep 9, 2026 — 72 cities hit, up to 2.75" | Overviewoverview.app
  11. 11Sep 9, 2026 Hail and Storm Summary | Hail Drivehaildrive.com

4. Market Data

Contract Snapshot

This market resolves YES if Hurricane Norbert reaches Category 3 or above, and NO if it does not. The maximum payout date for this market is December 1, 2026.

Available Contracts

Market options and current pricing

Outcome bucket Yes (price) No (price) Last trade probability
Category 1 or above $0.08 $0.98 7%
Category 2 or above $0.04 $0.98 5%
Category 3 or above $0.10 $0.99 0%
Category 4 or above $0.10 $0.99 0%
Category 5 or above $0.10 $0.99 0%

Market Discussion

As of September 13, 2026, Tropical Storm Norbert is not classified as a hurricane, with maximum sustained winds of 50 mph [1][2]. The National Hurricane Center forecasts indicate a weakening trend due to a hostile environment, expecting Norbert to degenerate into a remnant low by the middle of the week [3][4]. Prediction markets have tracked Norbert's potential to reach Category 1 hurricane status [5].

Sources (5)
  1. 1Tropical Storm Norbert Tracker | Weather Undergroundwunderground.com
  2. 2Tropical Storm Norbert Public Advisory Number 15 - je.st - Tropical Storm Norbert Public Advisory Number 15je.st
  3. 3Tropical Storm Norbert LIVE Tracker, Updates & Forecast | Zoom Earthzoom.earth
  4. 4Tropical Storm Norbert Forecast Discussion Number 14 - je.st - Tropical Storm Norbert Forecast Discussion Number 14je.st
  5. 5Hurricane Norbert category? - Kalshi oranları | CoinRithmcoinrithm.com

5. What specific atmospheric conditions caused the National Hurricane Center to downgrade its intensity forecast for Norbert between September 12 and September 13?

Forecast AdjustmentWeaker intensity trend for Tropical Storm Norbert (September 12-13, 2026) [1]
Initial Sept 12 ForecastPotential for hurricane within 24 hours (September 12, 2026) [2]
Later Sept 12 ObservationContinuing to weaken (evening advisory, September 12, 2026) [2][3]
Forecasts for Tropical Storm Norbert trended weaker between September 12-13, 2026. The National Hurricane Center (NHC) made minor adjustments to its intensity forecast, suggesting less strengthening than previously expected based on intensity models [1]. This led to a downgrade in the projected intensity for Tropical Storm Norbert during this period.
Atmospheric conditions mitigated Norbert's intensification despite favorable ocean temperatures. The NHC's assessment highlighted Norbert's sheared structure and the proximity of drier air to the west as key factors preventing rapid intensification [1]. These conditions acted as mitigating elements, even though the system was moving into a moist environment over warm 28–29°C waters [1].
Despite weakening, Norbert was still projected to reach hurricane strength. On September 12, 2026, the NHC initially forecasted Norbert to potentially become a hurricane within 24 hours [2]. However, by the evening advisory on September 12, the NHC noted that Norbert was continuing to weaken [2][3]. As of September 13, 2026, the NHC's forecast continued to predict that Norbert would reach hurricane strength by early the following week [1].
Sources (3)
  1. 1Tropical Storm Norbert LIVE Tracker, Updates & Forecast | Zoom Earthzoom.earth
  2. 2Tropical Storm Norbert Forecast Discussionnhc.noaa.gov
  3. 3Tropical Storm Norbert Public Advisory - National Hurricane Centernhc.noaa.gov

6. Based on the latest advisories from NOAA and the NHC, what is the official forecast track and intensity for Tropical Storm Norbert through September 16?

Current StatusActive tropical storm in Eastern Pacific (September 13, 2026) [1]
Maximum Sustained Winds40-50 mph (35-50 knots) (September 13, 2026) [1]
Forecast IntensityNot anticipated to reach hurricane intensity; degenerating into a remnant low by September 16, 2026 [2][3][4]
Tropical Storm Norbert maintains a westward track with no land impacts expected. As of September 13, 2026, the system is active in the Eastern Pacific Ocean, with maximum sustained winds of approximately 40-50 mph (35-50 knots) [1]. The official National Hurricane Center (NHC) forecast tracks Norbert on a persistent westward to west-northwestward path across open waters, with no land impacts currently anticipated [1][5].
Norbert is expected to weaken and dissipate by September 16, 2026. The NHC forecasts Tropical Storm Norbert to degenerate into a remnant low by Wednesday and dissipate thereafter [2][3]. Through its remaining life cycle, the storm is not forecast to reach hurricane intensity, which is defined as winds of 74 mph or greater [2][4].
Sources (5)
  1. 1Tropical Storm Norbert LIVE Tracker, Updates & Forecast | Zoom Earthzoom.earth
  2. 2Tropical Storm Norbert Forecast Discussionnhc.noaa.gov
  3. 3Tropical Storm Norbert Forecast Discussionnhc.noaa.gov
  4. 4Tropical Storm Norbert Forecast Advisory - National Hurricane Centernhc.noaa.gov
  5. 5Tropical Storm Norbert Intensifying Over Open Waters of the Eastern...sea.weathernews.com

7. How did the intensity predictions for Norbert from the main global weather models, such as the GFS and ECMWF, compare on September 11 versus September 13?

Period of intensity uncertaintySeptember 11-13, 2026 [1][2][3][4]
NHC classification on Sep 13Tropical Storm status [5][6][7][8][9][10][11]
High seas forecast projectionHurricane intensity (65 knots) within 24-48 hours (as of Sep 12, 2026) [12][13]
Global weather models showed uncertainty about Norbert's intensity from September 11-13. Between September 11 and September 13, 2026, major global weather models, including the GFS and ECMWF, indicated significant uncertainty regarding Tropical Storm Norbert's potential intensity. These forecasts suggested Norbert could either approach or reach hurricane intensity or maintain tropical storm status, influenced by atmospheric conditions such as wind shear [1][2][3][4].
Norbert remained a Tropical Storm despite some hurricane intensity projections. As of September 13, 2026, the National Hurricane Center (NHC) classified Norbert as a Tropical Storm, not a hurricane [5][6][7][8][9][10][11]. While some high seas forecasts issued on September 12, 2026, projected Norbert to reach hurricane intensity (65 knots) within 24 to 48 hours, the system maintained its tropical storm status through at least September 13, 2026 [12][13]. The available information does not provide granular details to specifically compare how the intensity predictions from the GFS and ECMWF models evolved or differed between September 11 and September 13.
Sources (13)
  1. 1Tropical Storm Norbert Forecast Discussionnhc.noaa.gov
  2. 2If model trend continues, Norbert could be a weaker system some of...facebook.com
  3. 3HURRICANE HQ: Norbert is expected to maintain Tropical Storm...facebook.com
  4. 4Tropical Storm Norbert churns in the Pacific, expected to weaken...foxweather.com
  5. 5Tropical Storm Norbert Graphics - National Hurricane Center - NOAAnhc.noaa.gov
  6. 6Tropical Storm Norbert Public Advisory - National Hurricane Centernhc.noaa.gov
  7. 7Tropical Storm Norbert Forecast Discussionnhc.noaa.gov
  8. 8Tropical Storm Norbert Wind Speed Probabilitiesnhc.noaa.gov
  9. 9Tropical Storm Norbert Forecast Discussionnhc.noaa.gov
  10. 10Tropical Storm Norbert Forecast Discussionnhc.noaa.gov
  11. 11Tropical Storm NORBERT Advisory Archivenhc.noaa.gov
  12. 12East and Central North Pacific High Seas Forecastocean.weather.gov
  13. 13High Seas Forecast - National Weather Servicemarine.weather.gov

8. What are the precise sustained wind speed thresholds, per the Saffir-Simpson Scale, that Norbert would need to cross to resolve as a Category 1, 2, or 3 hurricane?

Category 1 Hurricane Wind Speed74–95 mph [1][2][3][4]
Category 3 Hurricane Wind Speed111–129 mph [1][2][3][4]
Norbert's Current Status (Sept 13, 2026)Tropical storm with 45–50 mph winds [5][6][7]
Norbert requires specific sustained wind speeds to achieve hurricane categorization. To be classified as a Category 1 hurricane on the Saffir-Simpson Hurricane Wind Scale, Norbert's maximum sustained winds must reach 74–95 mph [1][2][3][4]. The wind speed thresholds escalate for higher categories, with a Category 2 hurricane defined by maximum sustained winds of 96–110 mph [1][2][3][4]. For Norbert to resolve as a Category 3 hurricane, which is considered a major hurricane, its maximum sustained winds would need to be between 111–129 mph [1][2][3][4].
The Saffir-Simpson Scale precisely defines hurricane wind thresholds. These specific wind speed requirements for hurricane classification are officially outlined by the Saffir-Simpson Hurricane Wind Scale [8][1][4]. As of September 13, 2026, Norbert is presently categorized as a tropical storm, with its maximum sustained winds recorded at approximately 45–50 mph [5][6][7].
Sources (8)
  1. 1Saffir-Simpson Hurricane Wind Scalenhc.noaa.gov
  2. 2Saffir-Simpson hurricane scale | Definition, Wind Speed, & Factsbritannica.com
  3. 3Saffir–Simpson scale - Wikipediaen.wikipedia.org
  4. 4Saffir-Simpson Hurricane Scale - National Weather Serviceweather.gov
  5. 5Tropical Storm Norbert Graphics - National Hurricane Center - NOAAnhc.noaa.gov
  6. 6Tropical Storm Norbert Tracker | Weather Undergroundwunderground.com
  7. 7Tropical Storm Norbert LIVE Tracker, Updates & Forecast | Zoom Earthzoom.earth
  8. 8The Saffir-Simpson Hurricane Wind Scale is a 1 to 5 categorization based on the hurricane's intensity at the indicated time. The scale – originally developed by wind engineer Herb Saffir and meteorologist Bob Simpson – has been an excellent tool for alerting the public about the possible impacts of various intensity hurricanes 1. The scale provides examples of the type of damage and impacts in the United States associated with winds of the indicated intensity. In general, damage rises by about a factor of four for every category increase 2. The maximum sustained surface wind speed (peak 1-minute wind at the standard meteorological observation height of 10 m [33 ft] over unobstructed exposure) associated with the cyclone is the determining factor in the scale. (Note that sustained winds can be stronger in hilly or mountainous terrain – such as the over the Appalachians or over much of Puerto Rico - compared with that experienced over flat terrain 3.) The historical examples provided in each of the categories correspond with the observed or estimated maximum wind speeds from the hurricane experienced at the location indicated. These do not necessarily correspond with the peak intensity reached by the system during its lifetime. It is also important to note that peak 1-minute winds in hurricane are believed to diminish by one category within a short distance, perhaps a kilometer [~ half a mile] of the coastline 4. For example, Hurricane Wilma made landfall in 2005 in southwest Florida as a Category 3 hurricane. Even though this hurricane only took four hours to traverse the peninsula, the winds experienced by most Miami-Dade, Broward, and Palm Beach County communities were Category 1 to Category 2 conditions. However, exceptions to this generalization are certainly possible. The scale does not address the potential for other hurricane-related impacts, such as storm surge, rainfall-induced floods, and tornadoes. It should also be noted that these wind caused damage general descriptions are to some degree dependent upon the local building codes in effect and how well and how long they have been enforced. For example, building codes enacted during the 2000s in Florida, North Carolina and South Carolina are likely to reduce the damage to newer structures from that described below. However, for a long time to come, the majority of the building stock in existence on the coast will not have been built to higher code. Hurricane wind damage is also very dependent upon other factors, such as duration of high winds, change of wind direction, and age of structures. Earlier versions of this scale – known as the Saffir-Simpson Hurricane Scale – incorporated central pressure and storm surge as components of the categories. The central pressure was used during the 1970s and 1980s as a proxy for the winds as accurate wind speed intensity measurements from aircraft reconnaissance were not routinely available for hurricanes until 1990 5. Storm surge was also quantified by category in the earliest published versions of the scale dating back to 1972 6. However, hurricane size (extent of hurricane-force winds), local bathymetry (depth of near-shore waters), topography, the hurricane’s forward speed and angle tonhc.noaa.gov

9. What low-probability environmental factors would need to materialize for Norbert to defy current forecasts and rapidly intensify before dissipation?

Current Maximum Sustained Winds50 mph (As of September 13, 2026) [1]
Official Forecast (Norbert)Degenerate into a remnant low by Tuesday and dissipate by Wednesday [2][3]
Rapid Intensification LikelihoodLow probability (requires significant environmental changes) [4]
Norbert is forecast to weaken and dissipate due to unfavorable conditions. Tropical Storm Norbert is currently in the eastern Pacific, with maximum sustained winds of approximately 50 mph as of September 13, 2026 [1]. Official National Hurricane Center (NHC) projections indicate limited near-term strengthening, primarily due to its sheared structure and the presence of nearby dry air [1]. Forecasters anticipate Norbert will degenerate into a remnant low by Tuesday and fully dissipate by Wednesday [2][3].
Rapid intensification requires specific conditions currently absent for Norbert. For a tropical storm to undergo rapid intensification (RI), typical environmental requirements include very low vertical wind shear, high ocean heat content, and a moist mid-tropospheric environment [5][6][7]. However, for Norbert to defy current forecasts and rapidly intensify before dissipation, it would necessitate significant and low-probability environmental changes [4]. These changes would include a major increase in ocean heat content or a sudden reduction in vertical wind shear [4]. Critically, these conditions necessary for rapid intensification are contrary to the atmospheric circumstances currently leading to Norbert's forecast degeneration [4].
Sources (7)
  1. 1Tropical Storm Norbert LIVE Tracker, Updates & Forecast | Zoom Earthzoom.earth
  2. 2Tropical Storm Norbert Graphics - National Hurricane Center - NOAAnhc.noaa.gov
  3. 3Tropical Storm Norbert Forecast Discussionnhc.noaa.gov
  4. 4Tropical Storm Norbert Public Advisory - National Hurricane Centernhc.noaa.gov
  5. 5On the processes influencing rapid intensity changes of tropical...pmc.ncbi.nlm.nih.gov
  6. 6The Unexpected Rapid Intensification of Tropical Cyclones in...journals.ametsoc.org
  7. 7Rapid versus slow intensification of idealized tropical cyclones using...rmets.onlinelibrary.wiley.com

10. What Could Change the Odds

Key Catalysts

Tropical Storm Norbert, the 16th named storm of an active 2026 Eastern Pacific hurricane season fueled by a strengthening El Niño, was initially forecast to intensify [1]. As of September 12, 2026, the National Hurricane Center (NHC) expected Norbert, then classified as a tropical storm with maximum sustained winds of 55 knots (approximately 63 mph), to become a hurricane within 24 hours [2][3].
However, the forecast has since shifted. As of Sunday, September 13, 2026, Norbert remains a tropical storm, not a hurricane, with maximum sustained winds of approximately 50 mph [4][5][6]. The NHC now expects Norbert to continue weakening, degenerating into a remnant low by Tuesday, September 15, 2026, and dissipating by Wednesday, September 16, 2026 [4][5][6]. This revised outlook suggests prediction markets, such as Kalshi and Polymarket, trading contracts on Norbert's potential to reach hurricane strength, are tracking toward resolution based on the storm failing to reach hurricane category [7][8][9].

Key Dates & Catalysts

  • Expiration: December 02, 2026
  • Closes: December 02, 2026
Sources (9)
  1. 1Tropical Storm Norbert churns in the Pacific, expected to weaken...foxweather.com
  2. 2East and Central North Pacific High Seas Forecastocean.weather.gov
  3. 3Tropical Storm Norbert Forecast Discussionnhc.noaa.gov
  4. 4Tropical Storm Norbert Public Advisory Number 15 - je.st - Tropical Storm Norbert Public Advisory Number 15je.st
  5. 5Tropical Storm Norbert Public Advisory Number 14 - je.st - Tropical Storm Norbert Public Advisory Number 14je.st
  6. 6Tropical Storm Norbert Tracker | Weather Undergroundwunderground.com
  7. 7Hurricane Norbert category? Odds & Predictions - Kalshikalshi.com
  8. 8Will Tropical Storm Norbert strengthen to a hurricane?polymarket.com
  9. 9Will Norbert be categorized as a hurricane in the Eastern… — 42% · Kalshi | SimpleFunctionssimplefunctions.dev

12. Related News

-77.0pp
Last updated: September 13, 2026, 12:14 UTC

NHC Forecasts Norbert to Weaken, Erasing Hurricane Odds in Markets

Forecasts from the National Hurricane Center on Saturday, September 12, 2026, projecting that Tropical Storm Norbert will weaken and dissipate without reaching hurricane intensity, prompted a signific...

13. Historical Resolutions

Historical Resolutions: 20 markets in this series

Outcomes: 14 resolved YES, 6 resolved NO

Recent resolutions:

  • KXHURCAT-26LOWELL-T5: YES (Sep 10, 2026)
  • KXHURCAT-26LOWELL-T4: YES (Sep 10, 2026)
  • KXHURCAT-26LOWELL-T3: YES (Sep 10, 2026)
  • KXHURCAT-26LOWELL-T2: YES (Sep 10, 2026)
  • KXHURCAT-26LOWELL-T1: YES (Sep 10, 2026)