Where will it rain on Sep 1, 2026?
Short Answer
It is likely to rain in New York City on September 1, 2026; the market prices this outcome at 99.0%.
1. Market Behavior & Drivers
The market's repricing was overwhelmingly driven by short-term weather forecasts as the resolution date approached. A forecast from The Boston Globe on August 31, which announced "September begins cool with showers" for New England, caused the contract's largest single movement. The price surged 66.0 percentage points, from 19.0% to 85.0%, directly following the news.
The final leg of the price move, an 11.0 point spike to 99.0% on September 1, coincided with an official government alert. On the resolution date, the National Weather Service Storm Prediction Center identified a slight risk of severe thunderstorms across parts of the region, solidifying the high probability of rain. These specific, near-term meteorological reports were the decisive factors, operating within a broader climate pattern influenced by a historically strong El Niño event.
- New York City, Boston, Newark probabilities reached 99% following recent price spikes.
- Tropical Storm Edouard presented a significant rainfall threat to New Orleans.
Who Wins and Why
| Outcome | Market | Model | Why |
|---|---|---|---|
| New York City | 99.0% | 99.0% | Frontal systems or tropical moisture often bring rain to the region. |
| Philadelphia | 82.0% | 82.0% | Afternoon thunderstorms and frontal activity are typical for early September. |
| Boston | 99.0% | 99.0% | Frontal passages frequently deliver rainfall to the Northeast. |
| Newark | 99.0% | 99.0% | This humid climate zone commonly experiences early September rain events. |
| Miami | 76.0% | 76.0% | Abundant tropical moisture often produces daily afternoon and evening showers. |
Current Context
Global climate patterns for September 1, 2026, are affected by El Niño. A historically strong El Niño event, reaching record or near-record strength, significantly influences global climate patterns in late 2026, impacting regional precipitation and temperature anomalies through the remainder of the year [^][^][^][^][^][^]. In Asia, the Philippines experienced rain in various parts of the country due to the Southwest Monsoon (Habagat), with Tropical Storm Pilandok also monitored within the Philippine Area of Responsibility [^]. The India Meteorological Department (IMD) forecast rain and thundershowers for Delhi-NCR and issued warnings of heavy to very heavy rainfall for Chhattisgarh, East Madhya Pradesh, Odisha, Uttarakhand, and parts of the Northeast [^][^].
The United States faces multiple severe weather threats on September 1. The US Storm Prediction Center forecast scattered strong to severe thunderstorms for parts of the central Plains, Midwest, New York, Pennsylvania, and New Jersey [^]. These scattered showers and thunderstorms are expected across New York, New Jersey, and Pennsylvania, associated with a warm front and a shortwave trough [^]. Strong to severe thunderstorms are also potential in portions of the central and northern Plains and Midwest as a stalled front lifts northward [^]. Additionally, a tropical system identified as Eduardo is located near 8.6N 91.6W, moving toward the southwest Louisiana and southeast Texas coasts [^].
Ireland expects rain development after a dry start. Met Éireann forecast a mainly dry Tuesday morning for Ireland on September 1, 2026, with persistent rain and worsening conditions developing later in the day [^].
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.
Outcome: Newark
📈 September 01, 2026: 20.0pp spike
Price increased from 79.0% to 99.0%
What happened: The primary driver for the 20.0 percentage point spike in the prediction market price for rain in Newark on September 1, 2026, was official weather forecasts. On September 1, 2026, the National Weather Service Storm Prediction Center identified a slight risk of severe thunderstorms across parts of New Jersey, including Newark, with showers and thunderstorms expected to persist throughout the day [^]. Additionally, local news reported potential for thunderstorms late in the afternoon and evening in Newark, which could cause localized flooding [^]. Given the absence of any social media activity in the provided information, these credible weather announcements likely coincided with and drove the market's increased probability for rain.
Outcome: Boston
📈 August 31, 2026: 73.0pp spike
Price increased from 14.0% to 87.0%
What happened: The primary driver of the prediction market price spike was a traditional news announcement forecasting rain. On August 31, 2026, The Boston Globe announced that "September begins cool with showers" for New England, explicitly forecasting rain for Boston on the target date of September 1, 2026 [^]. This news was significant, especially since August 2026 had been one of the driest Augusts on record for Boston, making the forecast for a wet start to September a notable development [^]. This credible weather forecast appeared to lead the price move, and social media activity was irrelevant based on the provided information.
4. Market Data
Contract Snapshot
A 'Yes' resolution occurs if it rains in the specified city on the given day, while a 'No' resolution occurs if it does not rain. This market resolves daily, reflecting the weather for "today." Settlement is determined by data from designated weather stations; specifically, Houston uses station CLIHOU, and all other cities listed rely on their existing, unchanged station sources.
Available Contracts
Market options and current pricing
| Outcome bucket | Yes (price) | No (price) | Last trade probability |
|---|---|---|---|
| Boston | $1.00 | $0.01 | 99% |
| New York City | $1.00 | $0.01 | 99% |
| Newark | $1.00 | $0.01 | 99% |
| Trenton | $0.89 | $0.19 | 88% |
| Philadelphia | $0.82 | $0.19 | 82% |
| Miami | $0.81 | $0.24 | 76% |
| Washington DC | $0.24 | $0.80 | 24% |
| Atlanta | $0.02 | $0.99 | 2% |
| Houston | $0.90 | $0.11 | 90% |
| New Orleans | $0.72 | $0.32 | 68% |
| Minneapolis | $0.40 | $0.61 | 39% |
| Chicago | $0.21 | $0.80 | 25% |
| Dallas | $0.28 | $0.80 | 21% |
| Austin | $0.23 | $0.82 | 12% |
| San Antonio | $0.07 | $0.94 | 8% |
| Oklahoma City | $0.01 | $1.00 | 1% |
| Denver | $0.13 | $0.88 | 13% |
| Seattle | $0.10 | $0.94 | 10% |
| San Francisco | $0.11 | $0.92 | 9% |
| Phoenix | $0.06 | $0.95 | 2% |
| Las Vegas | $0.01 | $1.00 | 1% |
| Los Angeles | $0.01 | $1.00 | 1% |
Market Discussion
Forecasts for September 1, 2026, indicated heavy rain and potential severe thunderstorms across parts of India (including Odisha, Chhattisgarh, Bihar, Jharkhand, and the Northeast states), Nepal, Bangladesh, Southeast Asia, and Japan [^][^]. In the United States, scattered showers and thunderstorms were forecast for the central/northern Plains, Midwest, parts of the Northeast (NY, PA, NJ), Hawaii (windward and mauka areas), and portions of southwest Oregon and northern California [^][^][^][^]. Public discussion reflects a divide on weather prediction markets, with some analysts suggesting they can aggregate human judgment to outperform traditional meteorological models, while critics raise concerns about the "gamification" of weather, potential for manipulation, and ethical implications [^][^][^][^].
5. Trader Dashboard
A deterministic, per-market integrity scorecard computed from order-book and price data. Higher is better for Trader Trust, Liquidity, Move Quality and Resolution; higher means more risk for Quote Risk and Avoid Risk.
New York CityPrimaryTrader Trust—Liquidity—Move Quality—Resolution—Quote Risk—Avoid Risk—
Move Quality—No significant move (6h)
- Factor
- move_log_odds
- 0
ChicagoTrader Trust—Liquidity—Move Quality—Resolution—Quote Risk—Avoid Risk—
Move Quality—No significant move (6h)
- Factor
- move_log_odds
- -0.10
AustinTrader Trust—Liquidity—Move Quality75Resolution—Quote Risk—Avoid Risk—
Move Quality75Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 86
MiamiTrader Trust—Liquidity—Move Quality76Resolution—Quote Risk—Avoid Risk—
Move Quality76Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 87
DenverTrader Trust—Liquidity—Move Quality72Resolution—Quote Risk—Avoid Risk—
Move Quality72Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 82
PhiladelphiaTrader Trust—Liquidity—Move Quality83Resolution—Quote Risk—Avoid Risk—
Move Quality83Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
Los AngelesTrader Trust—Liquidity—Move Quality—Resolution—Quote Risk—Avoid Risk—
Move Quality—No significant move (6h)
- Factor
- move_log_odds
- 0
Las VegasTrader Trust—Liquidity—Move Quality83Resolution—Quote Risk—Avoid Risk—
Move Quality83Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
New OrleansTrader Trust—Liquidity—Move Quality—Resolution—Quote Risk—Avoid Risk—
Move Quality—No significant move (6h)
- Factor
- move_log_odds
- 0.15
San FranciscoTrader Trust—Liquidity—Move Quality78Resolution—Quote Risk—Avoid Risk—
Move Quality78Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
Washington DCTrader Trust—Liquidity—Move Quality—Resolution—Quote Risk—Avoid Risk—
Move Quality—No significant move (6h)
- Factor
- move_log_odds
- -0.11
SeattleTrader Trust—Liquidity—Move Quality41Resolution—Quote Risk—Avoid Risk—
Move Quality41Mixed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 29
BostonTrader Trust—Liquidity—Move Quality85Resolution—Quote Risk—Avoid Risk—
Move Quality85Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
PhoenixTrader Trust—Liquidity—Move Quality76Resolution—Quote Risk—Avoid Risk—
Move Quality76Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
AtlantaTrader Trust—Liquidity—Move Quality—Resolution—Quote Risk—Avoid Risk—
Move Quality—No significant move (6h)
- Factor
- move_log_odds
- 0
MinneapolisTrader Trust—Liquidity—Move Quality81Resolution—Quote Risk—Avoid Risk—
Move Quality81Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
DallasTrader Trust—Liquidity—Move Quality73Resolution—Quote Risk—Avoid Risk—
Move Quality73Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
San AntonioTrader Trust—Liquidity—Move Quality83Resolution—Quote Risk—Avoid Risk—
Move Quality83Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
HoustonTrader Trust—Liquidity—Move Quality85Resolution—Quote Risk—Avoid Risk—
Move Quality85Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
Oklahoma CityTrader Trust—Liquidity—Move Quality82Resolution—Quote Risk—Avoid Risk—
Move Quality82Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
NewarkTrader Trust—Liquidity—Move Quality85Resolution—Quote Risk—Avoid Risk—
Move Quality85Confirmed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 100
TrentonTrader Trust—Liquidity—Move Quality50Resolution—Quote Risk—Avoid Risk—
Move Quality50Mixed
- Factor
- Factor
- flow_agreement
- 0.85
- move_retained_pct
- 49
trader_dashboard_lean_v1.14 · computed Sep 1, 2026
6. How is the 2026 El Niño expected to alter September precipitation patterns for West Coast cities like Los Angeles versus Gulf Coast cities like New Orleans?
| El Ni o Status (Sept 2026) | Active and strengthening, very strong event [^][^][^] |
|---|---|
| El Ni o Probability (Fall/Winter 2026-2027) | Greater than 90% chance of a very strong event [^][^] |
| Los Angeles Forecast (Sept 1, 2026) | Sunny conditions with no precipitation [^] |
A powerful El Niño is currently active in September 2026. This intense and potentially historic event is characterized by Niño 3.4 sea surface temperature anomalies indicative of a very strong event [^][^][^]. As of September 1, 2026, the El Niño event is active and strengthening, with a greater than 90% chance of a very strong event continuing throughout the fall and winter of 2026-2027 [^][^].
Early autumn precipitation signals are less definitive with El Niño. While strong El Niños typically correlate with wetter winters for both the West Coast and Gulf Coast, the precipitation signal for early autumn (September) is less conclusive than for the peak winter season [^][^][^]. For Los Angeles, September is usually dry [^][^][^]. Weather forecasts for September 1, 2026, indicated a low probability of measurable precipitation, consistent with its arid climate, predicting sunny conditions with no precipitation [^][^][^][^].
New Orleans maintains typical September rainy season conditions. For New Orleans, September falls within its active summer rainy season and had a forecasted risk of rain, which is typical of its climate and regional weather patterns [^][^][^][^][^][^]. However, as of September 1, 2026, no specific large-scale precipitation event was explicitly forecast for New Orleans for that day, although dangerous heat persisted across the Southern Plains and Lower Mississippi Valley [^][^]. The provided information does not contain enough detail to definitively describe how the 2026 El Niño is expected to alter September precipitation patterns for these cities beyond these typical conditions or specific September 1, 2026, forecasts.
7. How do long-range forecasts from models like the GFS and sources like the Farmers' Almanac align on precipitation chances for New York City and Philadelphia on September 1, 2026?
| Date of specific forecast | September 1, 2026 [^][^][^] |
|---|---|
| Long-range Sept forecast (Northeast) | Cooler and drier than average [^][^] |
| NYC NWS forecast (Sept 1, 2026) | Marginal risk of excessive rainfall [^] |
Long-range forecasts poorly predicted specific daily weather events. Long-range outlooks from sources like the Farmers' Almanac provided generalized forecasts that did not align with the specific daily weather conditions of September 1, 2026, for New York City and Philadelphia [^][^][^]. These sources, including The Old Farmer's Almanac, projected a generally cooler and drier-than-average September for the Northeast region [^][^]. This regional outlook contrasted sharply with the active, stormy weather, including high probabilities of rain and severe thunderstorms, that was observed on September 1, 2026 [^][^][^][^][^].
Short-term forecasts accurately predicted severe weather for September 1, 2026. In contrast, short-term operational forecasts, such as those from the National Weather Service (NWS), accurately predicted significant chances for rain and thunderstorms for September 1, 2026, in both New York City and Philadelphia [^][^][^]. For New York City, the NWS forecast included a marginal risk of excessive rainfall and identified isolated flash flood potential [^]. For Philadelphia, the NWS indicated chances for showers and thunderstorms, with localized probability of precipitation and potential for higher rainfall amounts within thunderstorms [^][^]. Models like the GFS are typically utilized for these short-range, high-resolution daily predictions, and long-range tools or monthly and seasonal outlooks do not serve as replacements for specific daily forecasts [^].
8. Which weather system poses a greater rainfall threat on September 1, 2026: the frontal system impacting Chicago or the tropical system near New Orleans?
| New Orleans Rainfall Risk | Marginal Risk (1 out of 4) [^] |
|---|---|
| New Orleans Rainfall Rate | 1-2 inches per hour [^] |
| Chicago Rainfall Chance | Slight (10-20%) [^][^][^] |
Tropical Storm Edouard posed a greater rainfall threat to New Orleans. On September 1, 2026, the tropical system near New Orleans presented a significantly higher rainfall threat compared to the frontal system impacting Chicago. This was primarily due to Tropical Storm Edouard bringing considerable rainfall to the New Orleans area, while Chicago experienced predominantly dry conditions [^][^][^][^][^][^][^].
Tropical Storm Edouard brought significant rainfall to the New Orleans region. Located near the northwestern Gulf Coast on September 1, 2026, Tropical Storm Edouard posed a substantial rainfall threat to the New Orleans area [^][^][^]. Forecasts predicted torrential rainfall, flash flooding, and storm surge as the tropical storm moved toward landfall near the Louisiana-Texas border [^][^][^]. The National Weather Service office in New Orleans/Baton Rouge reported a Marginal Risk (1 out of 4) for heavy rainfall as of that morning, with expected rates of 1-2 inches per hour in more intense storms [^].
Chicago experienced hot, humid, and predominantly dry weather. In contrast, Chicago, Illinois, faced a hot, humid, and largely dry weather pattern on September 1, 2026 [^][^][^]. The long-range forecast for Chicago for September 1-8, 2026, indicated "sunny" conditions, suggesting no significant frontal rainfall threat on the first of September [^]. There was only a slight (10-20%) chance of isolated, hit-or-miss showers or thunderstorms, and a Heat Advisory was in effect [^][^][^].
9. According to NOAA's historical data, how does the probability of rain on September 1 compare between arid cities like Las Vegas and humid cities like Miami?
| Miami September nighttime precipitation probability | 33% (1985-1997) [^] |
|---|---|
| Las Vegas September average monthly precipitation | 0.32 inches [^][^][^] |
| Miami forecast September 1, 2026 | Scattered to numerous showers and thunderstorms [^] |
Humid cities like Miami historically experience significantly higher rain probabilities. Humid regions such as Miami generally exhibit significantly higher historical probabilities of daily precipitation in early September compared to arid regions like Las Vegas, which are characteristically dry [^]. According to historical climatological data for South Florida between 1985 and 1997, the probability of nighttime precipitation in Miami for September is 33% [^].
Las Vegas, an arid city, historically sees minimal September precipitation. Las Vegas is an arid city where measurable precipitation of 0.01 inch or more on any given day is uncommon [^]. September in Las Vegas has an average monthly precipitation of 0.32 inches [^][^], further illustrating the minimal likelihood of daily rain compared to a humid climate.
Current forecasts for September 1 reflect these established climate patterns. As of September 1, 2026, the National Weather Service forecasts scattered to numerous showers and thunderstorms for Miami, Florida, indicating a high likelihood of rain [^]. Conversely, Las Vegas, Nevada, is projected to remain in a period of hot, dry weather, with no forecast of precipitation for the same date [^]. These forecasts align with the historical climate differences between the two regions, which are underpinned by NOAA's National Centers for Environmental Information's U.S. Climate Normals based on 30-year historical averages [^][^].
10. What evidence from satellite and reconnaissance data supports the National Hurricane Center's forecast for Tropical Storm Eduardo's impact on New Orleans?
| Storm intensification | From 40 mph to 50 mph [^][^][^] |
|---|---|
| Forecasted impact on New Orleans | Tropical storm conditions [^][^][^] |
| Forecasted landfall date and location | September 1, 2026, near Texas-Louisiana border [^][^][^][^] |
Satellite and reconnaissance data supported forecasts for Tropical Storm Edouard's impact. National Hurricane Center forecasts for Tropical Storm Edouard were supported by satellite imagery and reconnaissance data, including NWS radar data from Lake Charles (KLCH) [^][^][^][^][^]. This evidence demonstrated the storm's strengthening and an improving inner-core structure, which informed the forecast that New Orleans could experience tropical storm conditions [^][^][^][^][^]. As of September 1, 2026, observations tracked the storm's intensification from 40 mph to 50 mph as it neared the coast [^][^][^]. These observations also indicated warnings that the storm could potentially strengthen further into a hurricane before making landfall [^][^][^].
New Orleans was expected to experience tropical storm conditions despite a western landfall. Tropical Storm Edouard was forecast to move west-northwest, with an anticipated landfall on September 1, 2026, near the Texas-Louisiana border [^][^][^][^]. Although the primary impacts, such as heavy rain and storm surge, were expected in a small coastal section of southeast Texas and southwest Louisiana, New Orleans was specifically identified as a city that could experience tropical storm conditions [^][^][^].
11. What Could Change the Odds
Key Catalysts
Weather and climate prediction markets in 2026 are primarily driven by ENSO (El Ni R ño/La Ni R ña) cycles, monthly global temperature anomalies (NOAA/NASA/Copernicus data), and seasonal hurricane activity [^] [^] [^] [^] . Odds Hit 64% - Odds & Predictions | Prediction Hunt" data-source-lanes="traditional">[^]. Traders use ensemble model spreads and climate baseline comparisons to determine positions [^]. The market for weather forecasting services and AI-weather modelling is experiencing strong growth (7.5%-21.3% CAGR projected), driven by increased climate resilience planning, demand for hyperlocal precision, and government procurement of commercial satellite data [^][^][^][^].
Bullish catalysts for 2026 temperature records include a strong El Ni R ño development [^] [^] [^] . Odds Hit 64% - Odds & Predictions | Prediction Hunt" data-source-lanes="traditional">[^]. Bearish catalysts include potential volcanic eruptions, natural variability, and La Ni
R
ña strengthening, all of which heavily influence market pricing for 'hottest year' contracts [^][^][^].
On September 1, 2026, significant rainfall occurred across diverse global regions, including South Asia, parts of Southeast Asia, Indonesia, Japan, the Korean Peninsula, various regions in Europe, and sections of North America [^] [^] [^] . On the same day, Tropical Storm Edouard was identified near 29.0N 92.8W (off the coast of Louisiana), producing scattered moderate to strong convection and associated rainfall along the Gulf Coast [^][^]. The National Weather Service also issued a severe thunderstorm outlook, indicating a slight risk of storms across parts of the central/northern Plains, Midwest, Pennsylvania, New York, and New Jersey [^].
Key Dates & Catalysts
- Strike Date: September 02, 2026
- Expiration: September 03, 2026
- Closes: September 02, 2026
12. Decision-Flipping Events
- Trigger: Weather and climate prediction markets in 2026 are primarily driven by ENSO (El Ni R ño/La Ni R ña) cycles, monthly global temperature anomalies (NOAA/NASA/Copernicus data), and seasonal hurricane activity [^] [^] [^] [^] .
- Trigger: Traders use ensemble model spreads and climate baseline comparisons to determine positions [^] .
- Trigger: The market for weather forecasting services and AI-weather modelling is experiencing strong growth (7.5%-21.3% CAGR projected), driven by increased climate resilience planning, demand for hyperlocal precision, and government procurement of commercial satellite data [^] [^] [^] [^] .
- Trigger: Bullish catalysts for 2026 temperature records include a strong El Ni R ño development [^] [^] [^] .
14. Historical Resolutions
Historical Resolutions: 20 markets in this series
Outcomes: 6 resolved YES, 14 resolved NO
Recent resolutions:
- KXRAIN-26AUG30-TTN: YES (Aug 31, 2026)
- KXRAIN-26AUG30-SFO: NO (Aug 31, 2026)
- KXRAIN-26AUG30-SEA: NO (Aug 31, 2026)
- KXRAIN-26AUG30-SATX: NO (Aug 31, 2026)
- KXRAIN-26AUG30-PHX: NO (Aug 31, 2026)
