How much will it rain in New York City this weekend?
Short Answer
New York City is expected to receive at least 1 inch of rain this weekend, supported by the National Weather Service forecast predicting approximately 1.85–2.75 inches; the market prices this outcome at 98.0%.
1. Market Behavior & Drivers
This market's price action has been driven entirely by evolving weather forecasts for a nor'easter expected over the weekend of September 26-27, 2026. The most significant move was a 28.0 percentage point drop on September 24, which occurred after the Mayor's office announced updated, and presumably lower, rainfall projections for the storm. This announcement pulled the market's implied probability down from a high of 99.0% to 71.0%.
The market subsequently rebounded as storm forecasts solidified at higher totals. On September 25, news reports from major outlets projecting 2-3 inches of rain drove an 18.0 percentage point spike to 89.0%. This upward trend continued on September 26, with the price rising another 9.0 points to 98.0% after the National Weather Service New York office issued a point forecast predicting 1.85 to 2.75 inches of rain. The price action consistently reflects direct reactions to official guidance.
- Above 1.5 inches of rain is highly probable per National Weather Service forecasts.
- Exceeding 2.5 inches may be optimistic; National Weather Service predicts up to 2.75 inches.
- Outcomes above 3.5 inches appear highly optimistic, surpassing primary forecast ranges.
Who Wins and Why
| Outcome | Market | Model | Why |
|---|---|---|---|
| Above 1 inch | 98.0% | 97.3% | The official forecast predicts 1.85–2.75 inches, indicating strong likelihood of exceeding 1 inch. |
| Above 2.5 inches | 87.0% | 79.0% | The latest forecast range concludes at 2.75 inches, making estimates for exceeding 2.5 inches optimistic. |
| Above 2 inches | 88.0% | 84.5% | The specific forecast range begins below 2 inches, making current estimates for exceeding 2 inches optimistic. |
| Above 5 inches | 20.0% | 12.0% | Exceeding 5 inches is highly optimistic, as this surpasses even the "locally higher" projections. |
| Above 3.5 inches | 33.0% | 30.8% | The primary forecast concludes below 3.5 inches; "locally higher" amounts are a qualified risk. |
Current Context
A nor'easter is expected to deliver 2-3 inches of rain to New York City this weekend. NYC Emergency Management described this system, active from Friday evening September 25 through Sunday morning September 27, 2026, as bringing rain, strong winds, and coastal flooding [1]. The citywide rainfall forecast is 2–3 inches, with locally higher totals possible, reaching 4–5 inches where heavier rain repeatedly tracks over the same area [1]. The heaviest rain is anticipated mainly on Saturday, potentially starting early Saturday morning, and could continue through the weekend [1]. Winds are forecast to peak at 40–50 mph Friday night through Saturday night, then ease on Sunday [1]. Principal secondary hazards include minor roadway and underpass flooding, isolated flash flooding, coastal flooding at high tide, and downed trees or power lines [1]. Snowfall is not identified as a threat for this late-September setup [1].
Specific forecasts show varied rain chances and amounts for the upcoming weekend. The NWS New York office, updated September 23, 2026, provided varying outlooks [2]. One NWS forecast indicated partly sunny conditions on Saturday, September 26, with a 40% chance of showers, and mostly cloudy skies on Sunday, September 27, with a 40% chance of showers [3][2]. A separate NWS point/zone forecast projected a wetter scenario for the NYC area, with showers likely and a 70% chance on Saturday, estimating new rainfall of 0.50–0.75 inches [4][5]. Saturday night had a 50% shower chance, while Sunday had a 40% shower chance [4][5]. Point-style forecasts from Weather Underground for Manhattan Saturday showed approximately a 40% rain chance and 0.15 inches, with Sunday forecasts around NYC showing roughly a 50% chance and about 0.19–0.23 inches [6][7][8]. These station forecasts are lower than the citywide storm-total guidance because they represent localized and day-specific amounts [6][7][8]. NWS meteorologists described the broader setup as unsettled, with showers and possible thunderstorms, noting progressive storm motion that would likely limit flooding potential mainly to minor nuisance flooding in urban, low-lying, and poor-drainage areas [9][10].
Climate data and markets provide context; weekend totals are uncertain. New York City's long-run September rainfall average is about 4.31 inches [11]. Month-to-date precipitation through September 23 was 2.21 inches in Central Park, below the 1991–2020 normal of 3.28 inches [12]. Snow is not a realistic concern for late September in New York City, as NWS Central Park climatology reported 0.0 inches of snow for September 23 and month-to-date [13][14]. Prediction markets for full-month September 2026 Central Park precipitation showed the 4–5 inch bucket around 30–40% and the greater-than-6-inch outcome around 25% [11][15][16]. However, these are full-month markets, not direct weekend rainfall forecasts [11][15][16]. The retrieved NWS material does not provide a verified prediction-market price or a definitive citywide weekend rainfall total, and available forecast signals support rain chances but show meaningful timing and amount uncertainty [3][17].
Sources (17)
- 1Mayor Mamdani Issues Travel Advisory as Nor’easter Tracks Closer to New York City - NYC Mayor's Officenyc.gov
- 2New York, NYweather.gov
- 3National Weather Serviceforecast.weather.gov
- 47-Day Forecast 40.71N 74.01Wforecast.weather.gov
- 5Zone Area Forecast for New York (Manhattan) Countyforecast.weather.gov
- 6New York City, NY Hourly Weather Forecast | Weather Undergroundwunderground.com
- 7New York City, NY Hourly Weather Forecast | Weather Undergroundwunderground.com
- 8New York City, NY Hourly Weather Forecast | Weather Undergroundwunderground.com
- 9National Weather Serviceforecast.weather.gov
- 10National Weather Serviceforecast.weather.gov
- 11Precipitation in NYC in September 2026 | Lines.comlines.com
- 12National Weather Serviceforecast.weather.gov
- 13Climatological Report (Daily)forecast.weather.gov
- 14IEM:: NYC Data Calendar for Sep 2026mesonet.agron.iastate.edu
- 15Precipitation in NYC in September?polymarket.com
- 16Precipitation in NYC in September?probsee.com
- 17National Weather Serviceforecast.weather.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.
Outcome: Above 4 inches
📉 September 26, 2026: 58.0pp drop
Price decreased from 97.0% to 39.0%
What happened: The primary driver for the 58.0 percentage point drop was the release of an updated official weather forecast on September 26, 2026. The National Weather Service New York office updated its point forecast for New York City to predict approximately 1.85–2.75 inches of rain over the weekend [1][2]. This updated, lower forecast was significantly below the "Above 4 inches" threshold for the market outcome, making it substantially less likely [2]. Social media activity appears irrelevant as no related posts or viral narratives were identified in the provided research for this period.
Outcome: Above 2 inches
📈 September 25, 2026: 66.0pp spike
Price increased from 21.0% to 87.0%
What happened: The primary driver of the prediction market's 66.0 percentage point spike was traditional news and official announcements regarding an approaching nor'easter on September 25, 2026. Contemporaneous news reports from major outlets indicated forecasts of approximately 2–3 inches of rain in New York City over the weekend, with some localized totals potentially reaching 4–5 inches [3][4][5]. This widespread reporting of rainfall amounts exceeding 2 inches, coupled with city preparations for roughly 3 inches of rain, directly coincided with and supported the market's movement [3][4]. Social media activity was not identified in the provided research, indicating it was irrelevant to this price movement.
Outcome: Above 1 inch
📉 September 24, 2026: 28.0pp drop
Price decreased from 99.0% to 71.0%
What happened: The 28.0 percentage point drop in the "Above 1 inch" outcome on September 24, 2026, was primarily driven by a traditional news announcement regarding updated rainfall projections. On that day, the Mayor's office announced preparations for a nor'easter, stating that earlier forecasts for New York City had estimated "only about 1–1.5 inches" of rain [6]. This official communication, released on the same date as the market movement, likely represented a downward revision in expected rainfall totals compared to previous market expectations, leading to a significant decrease in confidence for the "Above 1 inch" outcome despite still being above the threshold. Social media activity was not a primary driver, as the available information on social channels was unrelated to the weather forecast [7].
Sources (7)
- 1NWS Forecast Office New York, NYweather.gov
- 2National Weather Serviceforecast.weather.gov
- 3NOR’EASTER: More heavy rain and wind expected in New York City this weekend as Mamdani issues travel advisory | amNewYorkamny.com
- 4New York City Emergency Management up and running to monitor nor'easter - CBS New Yorkcbsnews.com
- 5Nor'easter could bring days of rain. Maps show totals by regionusatoday.com
- 6Mayor Mamdani Prepares New Yorkers for Nor’easter - NYC Mayor's Officenyc.gov
- 7GPT-6 Hits AGI? Tech Euphoria 2.0, SF Mansion Shortage, NYC Bans AI in Schools & Venezuela Oil Dealyoutube.com
4. Market Data
Contract Snapshot
This Kalshi prediction market resolves based on the total rainfall in New York City between September 26 and September 27, 2026. A "YES" resolution occurs if the rainfall amount is above 4 inches. Conversely, a "NO" resolution is triggered if the rainfall is 4 inches or less. The maximum payout date for this market is September 28, 2026.
Available Contracts
Market options and current pricing
| Outcome bucket | Yes (price) | No (price) | Last trade probability |
|---|---|---|---|
| Above 0.5 inches | $0.99 | $0.34 | 99% |
| Above 1 inch | $0.94 | $0.18 | 98% |
| Above 1.5 inches | $0.96 | $0.42 | 97% |
| Above 2 inches | $0.96 | $0.21 | 88% |
| Above 2.5 inches | $0.96 | $0.19 | 87% |
| Above 3 inches | $0.74 | $0.61 | 47% |
| Above 4 inches | $0.72 | $0.63 | 38% |
| Above 3.5 inches | $0.75 | $0.64 | 33% |
| Above 5 inches | $0.45 | $0.92 | 20% |
| Above 4.5 inches | $0.47 | $0.99 | 7% |
Market Discussion
An official city advisory and initial National Weather Service (NWS) forecast indicated New York City could receive about 2–3 inches of rain citywide this weekend (Saturday–Sunday, September 26–27, 2026), with localized totals of 4–5 inches possible where heavier bands repeatedly pass [1][2]. However, later NWS extended forecasts for Saturday September 26 and Sunday September 27 predict lighter, scattered showers, with Saturday's rainfall generally under 0.10–0.25 inches and Sunday having a 50% chance of showers, leading to a practical estimate of a few tenths of an inch total, with substantial model uncertainty [3][4][5][6]. Prediction markets, primarily focused on total September precipitation rather than the specific weekend, suggest leading monthly buckets from 2–5 inches, but are characterized as thin and reflecting sentiment [7][8][9][10].
Sources (10)
- 1Mayor Mamdani Issues Travel Advisory as Nor’easter Tracks Closer to New York City - NYC Mayor's Officenyc.gov
- 2NOR’EASTER: More heavy rain and wind expected in New York City this weekend as Mamdani issues travel advisory | amNewYorkamny.com
- 37-Day Forecast 40.71N 73.98W - National Weather Serviceweather.gov
- 4National Weather Serviceforecast.weather.gov
- 5National Weather Serviceforecast.weather.gov
- 6Area Forecast Discussionweather.gov
- 7Will NYC have between 4 and 5 inches of precipitation in September? | Paritypredictparity.com
- 8NYC Weather | Prediction Market Forecastpredictmarketcap.com
- 9Rain in NYC in Sep 2026? | Paritypredictparity.com
- 10Precipitation in NYC in September 2026 | Lines.comlines.com
5. Trust Index
“Above 1.5 inches” made a sharp jump with almost no trading behind it.
Integrity risk· Thin-volume moves
How it adds up
Integrity80% of score72Good
Market integrity is low (51), but Integrity averages all three scores, so the other two pull it up. Only a critically low score would cap the total.
Trade quality20% of score60Caution
Includes the cost to trade: a $10,000 order can't be filled here because the order book is too thin.
Trust score70Good
Weighted blend with hard caps — a critically weak safety pillar, or a severe trading anomaly, caps the total regardless of the rest. Full methodology · About the Trust Index
Trust profile
Integrity4 screens run · 6 don't apply
6. How do rainfall forecasts from the National Weather Service and NYC Emergency Management compare for the weekend of September 26–27, 2026?
| NWS Forecast (Sept 24-25, 2026) | Approximately 2-3 inches citywide, with locally higher 4-5 inch totals possible [1][2] |
|---|---|
| NYCEM Public Briefing (Sept 24, 2026) | Approximately 1-1.5 inches of rain [3] |
| Citywide Storm-Total Forecast (Sept 26-27, 2026) | 2-3 inches, up from an earlier 1-1.5 inches [4] |
Early rainfall forecasts for the weekend of September 26–27, 2026, exhibited initial variations between the National Weather Service (NWS) and NYC Emergency Management (NYCEM). NYCEM's earlier public briefing on September 24 projected approximately 1–1.5 inches of rain from Friday afternoon through Sunday [3]. Conversely, NWS-associated guidance at an initial stage indicated a higher 2–3 inch weekend outcome, with potential for locally higher totals [1][2]. However, a direct comparison later indicated that NYCEM's public-facing estimate of 2–3 inches citywide, with local totals reaching 4–5 inches, became wetter than an NWS New York briefing's approximate 1–1.5 inches [4].
Forecasts converged to higher rainfall totals closer to the event. By September 24–25, 2026, the NWS-linked NYC forecast had been revised upward to approximately 2–3 inches of rain citywide for the Friday–Sunday storm period, with localized totals possibly reaching 4–5 inches in areas with heavier bands [1][2]. This revision by NWS represented a roughly 1–1.5 inch increase, occurring after the storm track shifted west toward New York City [1][3]. For the September 26–27 weekend, both NYCEM and the NWS-aligned city advisory ultimately forecast a nor’easter bringing rain from Friday evening through Sunday morning, with Saturday anticipated to have the heaviest rainfall [4].
Agencies shared a consensus on the storm's significant impact and timing. The citywide storm-total forecast ultimately converged to 2–3 inches, marking an increase from earlier predictions of 1–1.5 inches, with locally higher amounts still possible [4]. Both the NWS New York office activated an event page, and NYCEM initiated its Flash Flood Emergency Plan [4][5]. These actions signaled a shared expectation for a wet weekend, with peak rainfall anticipated on Saturday [4][5].
Sources (5)
- 1Mayor Mamdani Issues Travel Advisory as Nor’easter Tracks Closer to New York City - NYC Mayor's Officenyc.gov
- 2NOR’EASTER: More heavy rain and wind expected in New York City this weekend as Mamdani issues travel advisory | amNewYorkamny.com
- 3Mayor Mamdani Prepares New Yorkers for Nor’easter - NYC Mayor's Officenyc.gov
- 4Strong Winds and Moderate to Heavy Rain Expectedweather.gov
- 5NWS Forecast Office New York, NYweather.gov
7. What specific atmospheric dynamics are driving the high-end rainfall scenarios (4+ inches) for the incoming nor'easter?
| High-end rainfall scenario | 4+ inches for New York City [1][2][3][4][1][5] |
|---|---|
| Event duration | Friday night through Sunday [6][4][2][1][2][3] |
| Forecast precipitable water | Around 2 inches [6][4][7][8][9] |
NYC's 4+ inch rainfall hinges on specific atmospheric dynamics. High-end rainfall scenarios of 4+ inches for New York City are primarily driven by a combination of atmospheric dynamics, including a slow-moving, deepening offshore low and a decisive westward storm track shift [1][2][3][4][5]. A persistent east-northeast pressure-gradient flow into the NYC metro, generated by a strong Canadian high north of the storm interacting with the offshore low, sustains moisture transport, convergence, and prolonged wind-driven precipitation, rather than transient convective events [2][4][5].
Extended duration and abundant moisture are crucial for high rainfall. The event is characterized by multiple rounds of rain over a long duration, from Friday night through Sunday, with heavy-rain episodes persisting Saturday and overnight into Sunday [1][2][3][4][6]. This extended period is critical, allowing modest rainfall rates to accumulate into totals exceeding 4 inches [1][2][3][4][6]. Furthermore, the event is unusually potent and moisture-rich for late September, publicly forecasted as a large early-season nor’easter [4][6][7][8][9]. Substantial moisture availability, including forecast precipitable water around 2 inches, facilitates efficient warm-rain production and localized intense downpours [4][6][7][8][9].
Key meteorological ingredients contribute to significant track and rainfall uncertainty. Core meteorological ingredients supporting this event include a persistent eastern-U.S. upper trough, with shortwave and vorticity energy rounding its base, and a stalled or slowly moving frontal boundary that supports low-level lift and repeated precipitation waves [8][9]. The NWS New York forecast discussion notes a closed 500-mb low near the forecast area, with a surface low tracking near the 40°N/70°W benchmark on Saturday and meandering through the weekend [10][11]. This cutoff-low configuration introduces unusually high uncertainty in both storm track and rainfall [10][11]. Specifically for New York City, achieving a 4+ inch outcome would necessitate a major westward track shift, prolonged banding or repeated waves of precipitation, or localized convective training, none of which are present in the cited official baseline forecast [10][11].
Sources (11)
- 1Track where a potent nor’easter will bring heavy rain, winds and waves - The Washington Postwashingtonpost.com
- 2Tricky Nor’easter to bring multiple impacts to the Mid-Atlantic and southern New England this weekend – Balanced Weatherbalancedweather.com
- 3Wx4cast: A significant Nor'easter!wx4cast.blogspot.com
- 4Nor'easter brings strong winds, coastal flooding and high waves to East Coast - ABC Newsabcnews.com
- 5NWS Area Forecast Discussionweather.gfc.state.ga.us
- 6LIVE UPDATES: Nor'easter threatens millions with coastal flooding, heavy rain and high windsweather.com
- 7Millions in the US Northeast brace for a powerful stormphys.org
- 8National Weather Serviceforecast.weather.gov
- 9National Weather Serviceforecast.weather.gov
- 10Area Forecast Discussionforecast.weather.gov
- 11National Weather Serviceforecast.weather.gov
8. What is the forecasted timing for the heaviest rainfall bands over NYC between Saturday, September 26 and Sunday, September 27?
| Main heavy-rain window | Saturday [1][2] |
|---|---|
| Strongest rain expected | Saturday morning and continuing through Saturday [2][3] |
| Highest-risk window | Saturday evening through early Sunday morning, roughly 8 PM–6 AM EDT [4][5] |
The heaviest rainfall in NYC was forecasted for Saturday, September 26. The forecast indicated that Saturday was expected to have the heaviest rainfall over NYC, with the strongest rain potentially beginning early Saturday morning and continuing throughout the day [2][3]. Peak impacts of the storm were also anticipated on Saturday [2][3]. According to the best available evidence, the heaviest NYC-area rainfall was projected from late Saturday, September 26, into the overnight period and potentially early Sunday, September 27 [5][6]. For practical timing, the highest-risk window was approximately Saturday evening through early Sunday morning, with the strongest banding most likely late Saturday night, roughly 8 PM–6 AM EDT [4][5]. However, the exact timing and placement of shower and thunderstorm bands had limited confidence, as the National Weather Service explicitly noted these could shift by a few hours [6]. Official guidance consistently placed the main heavy-rain window on Saturday rather than Sunday [1][2].
Rain was expected to continue overnight, easing gradually on Sunday. Rain was forecast to persist through Saturday night, with approximately another 0.5–1 inch possible overnight [7][8]. Sunday, September 27, was expected to remain wet with rain or showers, but generally with less intensity, gradually easing later in the day and evening [7][8].
Sources (8)
- 1Area Forecast Discussionforecast.weather.gov
- 2Mayor Mamdani Issues Travel Advisory as Nor’easter Tracks Closer to New York City - NYC Mayor's Officenyc.gov
- 3NYC, NJ nor'easter timeline: When high winds, heavy rain, coastal flooding are expected | FOX 5 New Yorkfox5ny.com
- 47-Day Forecast 40.71N 73.98Wforecast.weather.gov
- 5WWA Summary by Location for 40.58N 74.16W with NYZ074/NYC085/NYZ212 emphasis Coastal Flood Statementforecast.weather.gov
- 6National Weather Serviceforecast.weather.gov
- 7NYC Weekend Weather Forecast: Rain, Wind And Coastal Floodinghoodline.com
- 87-Day Forecast 40.85N 73.87Wforecast.weather.gov
9. Which specific NOAA observation site will serve as the official measurement source for this market's resolution?
| Official Measurement Source | NOAA/NWS Central Park, New York City climate station [1][2][3] |
|---|---|
| NOAA Station ID | GHCND:USW00094728 [4] |
| NWS Operational Identifier | KNYC [5] |
The Central Park climate station serves as New York City's official measurement source. The National Oceanic and Atmospheric Administration (NOAA) and the National Weather Service (NWS) designate this site as the official observation location for the city [1][2][3]. Operationally, the station is labeled “New York City, Central Park” and uses the identifier KNYC [5]. Its precise location is approximately 40.77898° N, 73.96925° W, and it is also identified by the NOAA station ID GHCND:USW00094728 (or USW00094728) [4][6].
Central Park is considered the primary site for New York City's climate and precipitation data. NWS New York's climate materials specifically list Central Park as the main location, distinguishing it from other regional airports such as LaGuardia, JFK, and Newark [7]. For markets based on precipitation, such as a weekend covering September 26–27, 2026, the NWS daily climate and precipitation records for Central Park (NYC/KNYC) provide the official measurement series [8][9]. This designation is further corroborated by the Iowa Environmental Mesonet, which maps the NYC ASOS station to “NEW YORK CITY” using GHCN ID USW00094728, confirming Central Park as the definitive source over other metropolitan-area airports for settlement purposes [10][11].
Sources (11)
- 1Precipitation in NYC in September?polymarket.com
- 2Precipitation in NYC in September? — OMINARIominari.com
- 3100 Years of Weather Observations at Belvedere Castle in...vlab.noaa.gov
- 4Daily Summaries Station Details: NY CITY CENTRAL PARK, NY US, GHCND:USW00094728 | Climate Data Online (CDO) | National Climatic Data Center (NCDC)ncdc.noaa.gov
- 5New York City, Central Parkweather.gov
- 6National Weather Service New York, NY Hydro...weather.gov
- 7Local Climatological Dataweather.gov
- 8Central Park, NY Historical Dataweather.gov
- 9National Weather Serviceforecast.weather.gov
- 10Site Info: NYC NEW YORK CITY - IEMmesonet.agron.iastate.edu
- 11IEM:: NYC Data Calendar for Jun 2026mesonet.agron.iastate.edu
10. How does the official forecast for September 26-27, 2026 compare to historical rainfall data for late-September nor'easters in New York City?
| Forecasted Rainfall Sept 26-27, 2026 | 2–3 inches citywide (up to 4–5 inches locally) [1][2] |
|---|---|
| Central Park Rainfall Sept 29, 2023 | 5.80–5.86 inches [3][4][5] |
| Typical Central Park September Rainfall | 4.31 inches [6][7][8][9] |
The official forecast for the upcoming nor'easter indicates substantial rainfall. The official forecast for September 26–27, 2026, predicts 2–3 inches of rain across New York City, with localized totals potentially reaching 4–5 inches due to repeated heavy bands [1][2]. This updated forecast represents an increase from an earlier estimate of 1–1.5 inches [1]. Extended forecasts for the weekend, which sum daily predictions, largely align with the 2–3-inch range, suggesting approximately 1.77 to 2.75 inches of rain, alongside windy conditions with gusts up to 45 mph [2][10][11][12].
Forecasted rainfall totals are generally lower than significant historical events. While the predicted 2–3 inches of rain is considerable for late September, it generally falls below the amounts observed in major historical coastal storms [1][2][6][3][4]. For instance, a late-September 2023 coastal storm delivered 5.80–5.86 inches at Central Park and 8.65 inches at JFK over September 28–29 [3][4][5]. A weekend total of 2–3 inches would constitute roughly half to three-quarters of New York City's typical entire September rainfall, which averages between 3.58 and 4.31 inches across NYC airports and Central Park [6][7][8][9]. However, the potential for localized heavy bands could still push totals to 4–5 inches, aligning with the lower range of historical extreme rainfall amounts [1][2][3][4].
Sources (12)
- 1Mayor Mamdani Issues Travel Advisory as Nor’easter Tracks Closer to New York City - NYC Mayor's Officenyc.gov
- 2New York 14 Day Extended Forecast - Weathertimeanddate.com
- 3How much rain fell in NYC, NY, NJ and CT - ABC7 New Yorkabc7ny.com
- 4PowerPoint Presentationweather.gov
- 5National Weather Servicepreview-forecast.weather.gov
- 6CENTRAL PARK NY SEPTEMBER ALMANACweather.gov
- 7LAGUARDIA NY SEPTEMBER ALMANACweather.gov
- 8EWR_New_AbridgedVersion_September_Almanac_Finalized_READY3 (1).xlsmweather.gov
- 9* occurred in multiple yearsweather.gov
- 10National Weather Serviceforecast.weather.gov
- 11National Weather Serviceforecast.weather.gov
- 12National Weather Serviceforecast.weather.gov
11. What Could Change the Odds
Key Catalysts
Forecasts indicate a strong likelihood of measurable precipitation in New York City over the September 26–27, 2026 weekend. The National Weather Service (NWS) predicted rain throughout Saturday, September 26, with a 90% probability and expected daytime accumulation of 0.5–0.75 inches, followed by an additional 0.75–1.0 inches Saturday night [1][2]. For Sunday, September 27, the NWS forecast a 90% chance of rain with 0.5–0.75 inches during the day and a 70% chance of rain with 0.1–0.25 inches possible Sunday night [1][2]. This implied a weekend total of roughly 1.75–2.75 inches from Saturday daytime through Sunday night if forecast ranges were realized [1][2]. Other local forecasts supported rain showers on both days, with approximately 0.62 inches expected across the cited day/night periods [3][4][5].
The rain is driven by a powerful nor'easter expected to bring waves of precipitation through Saturday and Sunday, with the steadiest rain after dark on Saturday [5][6]. In addition to rain, strong northerly winds are expected, with gusts around 45–55 mph in the region and up to 61 mph at Republic Airport [5][3][4]. Coastal flooding is also a hazard, particularly in low-lying areas of Queens, Brooklyn, Staten Island, and Long Island [5][3][4]. These conditions, including wind and coastal flood advisories, were cited as strongly bearish for dry/no-rain outcomes for a rain-related prediction market [7].
The prediction market contract resolves "Yes" if official CLINYC precipitation is strictly greater than 0 inches on either September 26 or September 27, 2026 [8][9]. The detailed forecasts materially support a "Yes" outcome, as any measurable precipitation above 0 inches on either day would trigger settlement [3][4][8]. Bearish risks for this contract include station-specific dry readings, precipitation recorded only as trace or missing (which counts as zero), or a forecast bust resulting in zero precipitation on both days [3][4][8]. The market page indicated an 81% implied probability for New York City to experience rain [8][9].
Key Dates & Catalysts
- Expiration: October 04, 2026
- Closes: September 28, 2026
Sources (9)
- 1National Weather Serviceforecast.weather.gov
- 2National Weather Serviceforecast.weather.gov
- 3New York City, NY Hourly Weather Forecast | Weather Undergroundwunderground.com
- 4New York City, NY Hourly Weather Forecast | Weather Undergroundwunderground.com
- 5NYC braces for two days of rain and wind as coastal flooding threat grows - Gothamistgothamist.com
- 6NYC weather: Nor'easter conditions headed toward...silive.com
- 7New York, NYweather.gov
- 8Where will it rain this weekend (Sep 26 - Sep 27)? - Kalshi Odds | CoinRithmcoinrithm.com
- 9Where will it rain this weekend (Sep 26 - Sep 27)robinhood.com
