Best Tornado Prediction Market Sites and Apps 2026: Trade on Monthly Tornado Counts and Outbreaks
Mike Goodpaster Last Verified
15/07/2026
Tornado prediction markets let you trade on how many confirmed tornadoes will be reported in the US during a given month. Each contract is a monthly count bracket, and the outcome resolves on official data from NOAA's Storm Prediction Center. It is one of the more analytically tractable weather categories because historical tornado frequency data is publicly available and the primary drivers of seasonal activity are well understood.
This page covers the best sites for tornado prediction markets, how the bracket format works, what the settlement process looks like, which signals move prices, and how to get started.
Best Sites for Tornado Prediction Markets
Both Kalshi and Polymarket carry monthly tornado count contracts. Kalshi is the primary destination for US-based dollar traders. Polymarket has a broader weather catalog and runs tornado markets alongside its international climate category, which currently requires USDC for US traders.
| Prediction market site | Welcome offer | Tornado coverage | Funding |
|---|---|---|---|
| Kalshi | $10 bonus | Monthly US tornado count brackets; natural disaster category | ACH, debit card, PayPal, Venmo, crypto |
| Polymarket | Deposit $20 get $50 | Monthly tornado brackets; broader weather and climate catalog; international platform for US traders | USDC (Polygon), crypto wallet required |
| OG | Trade $20 get $20 | Selected severe weather and natural disaster contracts | ACH, debit card, crypto |
| Crypto.com | 100% up to $250 | Selected climate and natural event contracts | ACH, debit card, Apple Pay, Google Pay, crypto |
Kalshi
- Sports, politics, and crypto predictions
- Economics, culture, and climate events
- Optimized Android and iOS apps
- 2% debit card deposit fee
Kalshi runs monthly US tornado count contracts as part of its broader natural disasters and climate category. The format is a bracket structure, with each bracket covering a range of tornado counts and a separate Yes/No contract running on each. Settlement uses NOAA Storm Prediction Center official data, and the contract rules name the SPC as the resolution source before you trade. Kalshi is the cleanest dollar-native option for US traders who want to take a position on tornado frequency based on meteorological analysis, seasonal patterns, or ENSO conditions without dealing with crypto infrastructure.
New users get a $10 bonus after placing $10 in trades with no promo code needed. Kalshi accepts ACH, debit card, PayPal, and Venmo and is live in all 50 US states. The weather and climate section of the Kalshi app sits alongside the full range of event contract categories, and the Ideas section lets traders share meteorological analysis and propose new market parameters based on developing severe weather patterns.
Polymarket
- Polymarket is live in the USA
- Easy pick-up-and-trade mechanics
- Sign-up rewards may be available
- Beginner-friendly platform
- Dynamic trading topics
- Long wait list to join
- High regulatory scrutiny
- Not all markets are available yet
Polymarket runs monthly US tornado count contracts as part of its broader weather and climate catalog, which currently has 200-plus active weather markets. The tornado bracket format is similar to Kalshi's, dividing the month's expected count into ranges and running a contract on each. Polymarket also carries related severe weather contracts beyond tornado counts, including questions on specific outbreak events or whether a major tornado will affect a particular state in a given period. The platform's global user base includes traders with genuine meteorological backgrounds, particularly in active tornado season months where position sizes tend to be larger than on lighter weather markets.
For US traders, Polymarket's weather markets are currently only accessible through the international version of the platform, which requires USDC and a compatible crypto wallet. New users who deposit $20 or more receive a $50 trading bonus. The Polymarket iOS app is well-designed and easy to navigate across the full weather market catalog.
OG
- Owned by Crypto.com
- Up to $150 referral bonus
- Well-designed Android and iOS app
- No culture prediction markets yet
OG covers selected severe weather and natural disaster contracts as part of its broader prediction market catalog. For US traders who already use OG for sports or culture markets, checking for active tornado count contracts during peak spring tornado season requires no separate account setup. OG operates on the same CFTC-regulated infrastructure as Crypto.com, giving it the same regulatory protections and account structure, with ACH, debit card, and crypto all accepted for deposits.
New users receive a Trade $20 get $20 welcome offer. The OG interface is designed for casual trading rather than specialist meteorological analysis, which suits traders who want to enter a single bracket position based on seasonal patterns rather than monitoring model output on a six-hour cycle. Coverage is narrower than Kalshi on the specific tornado count bracket format, but the platform is worth checking during major outbreak periods when markets are most likely to be active.
Crypto.com
- Great range of sports predictions
- Simple fee structure
- Stylish website and mobile apps
- Good trade volume for its predictions
- The app is geared towards crypto trading
- No welcome bonus
Crypto.com covers selected climate and natural event contracts including severe weather categories. Like OG, the coverage is less systematic than Kalshi's dedicated tornado bracket section, but climate and natural disaster contracts appear during active weather periods. Crypto.com's Hollywood.com partnership is primarily for entertainment markets, but the broader platform infrastructure supports natural event contracts through its financials and culture categories.
New users who sign up through our link receive a 100% deposit match up to $250, the largest welcome offer on this page. The Crypto.com app holds a 4.7-star rating across more than 320,000 App Store reviews and supports Apple Pay and Google Pay for deposits alongside ACH and debit card. The dual $1 and $10 contract format gives tornado traders more position sizing flexibility than sites limited to a single contract size.
How Tornado Count Contracts Work
A monthly tornado count contract asks one question: how many confirmed tornadoes will the NOAA Storm Prediction Center report for the US in the given calendar month? That total is divided into numerical brackets, and a separate Yes/No contract runs on each bracket simultaneously. For more on how this binary contract format works across all prediction market categories, see our guide on how prediction market contracts are structured.
A typical set of brackets for a peak-season month like April or May might look like this:
| Bracket | Example Yes price | What it implies |
|---|---|---|
| Below 100 tornadoes | $0.04 | 4% chance: an extremely quiet month for a peak-season period |
| 100 to 129 | $0.08 | 8% chance: well below the historical average |
| 130 to 159 | $0.15 | 15% chance: a below-average month |
| 160 to 189 | $0.25 | 25% chance: slightly below average |
| 190 to 219 | $0.28 | 28% chance: near the historical mean for June |
| 220 to 249 | $0.12 | 12% chance: an above-average month |
| 250 to 279 | $0.05 | 5% chance: a well above-average month |
| 280 and above | $0.03 | 3% chance: a very active outbreak month |
Reading the full bracket set gives you the market's current probability distribution for the month's total. The brackets with the highest prices are where market participants are concentrating their bets. Prices shift throughout the month as the actual count accumulates and SPC weekly summaries arrive.
How Tornado Contracts Settle
Settlement uses NOAA Storm Prediction Center official data. The SPC publishes confirmed tornado counts from storm survey reports, Doppler radar analysis, and ground-truth field surveys. The preliminary monthly total is typically available within a few days of month end and usually finalises within about a week. A June contract, for example, would typically resolve around July 8, giving the SPC time to process late-cycle reports from the final days of the month.
An important nuance: the SPC distinguishes between preliminary reports and confirmed counts. A tornado sighting that appears in initial storm reports may be downgraded, upgraded, or split into multiple separate tornadoes during the survey process. The contract resolves on the final confirmed count for the month as published by the SPC, not on preliminary real-time tracking. This means the resolution number can differ from what you see in real-time SPC storm reports during the month. Always check whether the specific contract uses the preliminary or final SPC count, as this can affect contracts that are close to a bracket boundary.
What Drives Tornado Count Contracts
Tornado frequency in any given month is driven by atmospheric ingredients that are measurable and publicly available through NOAA data products. Traders who understand these signals have a genuine informational edge. For more on how weather contract prices respond to model updates generally, see our hurricane prediction markets page for context on how similar atmospheric dynamics affect storm market pricing. For the broader weather category overview including all sub-pages, see our weather prediction markets hub.
- CAPE (Convective Available Potential Energy). CAPE is the primary measure of atmospheric instability that fuels severe convection and tornado formation. High CAPE values across the central US in spring indicate a volatile atmosphere where supercell thunderstorms and tornado-producing squall lines are more likely. CAPE is published in real-time by NOAA's operational models and is the most direct ingredient-based signal for tornado count contracts.
- Wind shear profiles. Tornadic supercells require a specific combination of directional and speed wind shear through the troposphere. Deep-layer and low-level shear forecasts, available in NOAA's SPC daily convective outlooks, are a forward indicator of tornado-favorable environments. A week with sustained strong shear and high CAPE across Tornado Alley is a signal to check whether count contracts are still pricing near-average outcomes.
- ENSO state (El Niño/La Niña). La Niña conditions are historically associated with higher tornado frequency in the Great Plains, particularly in spring. The current ENSO state from NOAA's Climate Prediction Center is a baseline adjustment for any tornado count view: a La Niña spring should command higher expected counts than an El Niño spring, all else equal.
- SPC convective outlooks and mesoscale discussions. The SPC publishes day-1 and day-2 severe weather outlooks that include explicit tornado probability areas. An SPC High Risk outlook for tornado-prone areas is one of the strongest near-term signals that active reports will accumulate quickly. SPC Mesoscale Discussions, published in real time when a threatening situation is developing, update faster than the formal outlooks and are watched closely by tornado traders.
- Accumulated SPC reports through the month. Once a month is underway, the running count of confirmed tornadoes is the most direct input into repricing existing brackets. A week with several large outbreak days can shift the entire bracket distribution by moving the expected total well above its previous range, causing lower brackets to collapse in price and higher brackets to spike.
Tornado Season Calendar
Tornado frequency in the US follows a predictable seasonal pattern, which directly affects how much liquidity is available and how actively tornado count contracts trade across the year.
| Period | Activity level | Primary active region | Contract trading interest |
|---|---|---|---|
| March to May | Peak | Southern Plains, Tornado Alley (Texas, Oklahoma, Kansas) | Highest liquidity and trading volume |
| June | High | Northern Plains, upper Midwest | Active, particularly early in the month |
| July to August | Moderate | Northern Plains, Southeast | Lighter than spring peak |
| September to November | Secondary peak | Southeast corridor | Moderate; autumn outbreaks can surprise |
| December to February | Low | Gulf Coast, Southeast | Minimal; contracts often thin or inactive |
How to Start Trading Tornado Prediction Markets
Tornado count contracts run on a monthly cycle, with a new contract opening each month. Having your account set up before the active spring season begins means you can enter positions at the start of a month rather than mid-cycle when some of the count has already accumulated.
- Create and verify your account: Sign up on your chosen site and complete KYC with a government-issued ID. Required before depositing or trading.
- Fund your account: Kalshi and OG accept ACH, debit card, and other dollar methods. Polymarket requires USDC via the international platform.
- Navigate to the tornado contracts: Look in the Climate, Weather, or Natural Disasters category. Tornado count contracts are typically labeled by month (e.g. "US Tornado Count: April").
- Read the full bracket set: Check all active brackets for the current month simultaneously. The full set gives you the market's probability distribution and shows where the most uncertainty lies.
- Check the resolution criteria: Confirm whether the contract uses the preliminary SPC count or the final confirmed count, and check the resolution date (typically around eight days after month end).
- Choose your bracket and set your size: Enter Yes on the bracket you expect the count to land in, or No if you believe the count will miss that bracket. Market orders fill immediately; limit orders let you set a target price.
- Monitor SPC weekly summaries: The SPC publishes weekly severe weather summaries that update the running count. Checking these keeps your position calibrated against actual reported activity as the month progresses.
Tips for Trading Tornado Prediction Markets
Use historical SPC data to build a baseline
The SPC publishes complete historical tornado count data by month going back decades. Before entering any bracket, checking the historical average and median for that calendar month gives you an anchoring point. A contract that prices the 190-219 bracket at $0.20 when the historical June average is 200 is mispriced relative to history unless there is a specific pattern suggesting a departure.
Watch the first two weeks closely
The first two weeks of a month tend to set the tone. If the SPC is already tracking 80 confirmed tornadoes by mid-month in a period where the average full month is 150, the upper brackets reprice sharply upward. Entering a bracket position after you have two weeks of actual data is less risky than entering at the start of the month, though the price will reflect that reduced uncertainty.
Check ENSO conditions before spring contracts
La Niña transitions historically increase Great Plains tornado frequency in spring. If NOAA's Climate Prediction Center is forecasting a La Niña state through April and May, that is a systematic upward adjustment to expected counts relative to a neutral or El Niño pattern. Checking the CPC's ENSO outlook before trading peak-season contracts adds real analytical value.
Be cautious about data source risk
Tornado contracts resolve on SPC data, and the SPC is a federal agency whose budget and staffing are subject to government policy. Disruptions to SPC operations, whether through government shutdowns or agency reorganisations, could delay the publication of confirmed count data and therefore delay contract resolution. Always check the specific resolution criteria for how delayed data is handled before entering a long-duration tornado count position. For more on how prediction market sites handle edge cases in resolution, see our guide on what slippage means in prediction markets.
The Bottom Line on Tornado Prediction Markets
Tornado count contracts are one of the more analytically grounded weather prediction market categories. Historical frequency data is extensive and publicly available, the primary atmospheric ingredients are measurable in real time, and the settlement source is official and unambiguous. Peak activity in spring (March through June) generates the most liquidity, while winter months are quiet. Traders who follow SPC convective outlooks, understand CAPE and shear dynamics, and track ENSO conditions have a genuine, publicly available informational edge.
For more on the weather category, see our pages on hurricane prediction markets and the broader earthquake prediction markets page.
Tornado Prediction Markets FAQ
Which sites offer tornado prediction markets?
Kalshi runs monthly US tornado count bracket contracts as the primary US-accessible dollar-funded option. Polymarket also carries tornado count markets as part of its broader weather catalog but requires the international platform with USDC for US traders. OG and Crypto.com cover selected severe weather contracts during active tornado periods.
How do tornado count contracts work?
Each contract covers a single calendar month and divides the expected US tornado count into numerical brackets. Multiple bracket contracts run simultaneously. You pick Yes on the bracket you expect the count to land in. All brackets for the same month should sum to roughly 100% probability, making the full set a probability distribution over possible outcomes.
How are tornado count contracts settled?
Contracts resolve on the official confirmed tornado count published by NOAA's Storm Prediction Center. The SPC preliminary monthly total typically finalises within about a week after month end. Resolution dates are set around eight days after month end to allow the SPC to process late-cycle survey reports.
What is the difference between preliminary and confirmed tornado counts?
The SPC publishes preliminary tornado reports during and immediately after events, which can later be revised up or down during the formal survey process. Preliminary counts can differ from final confirmed counts, particularly when tornadoes are later found to be multiple separate tracks or a single continuous track rather than separate events. Always check whether the specific contract resolves on preliminary or confirmed figures.
When is tornado season, and when are these markets most active?
The primary US tornado season runs from March through June, with a secondary peak in autumn across the Southeast. Spring contracts, particularly April and May, generate the most trading volume. Winter contracts are quiet given low historical tornado frequencies and limited market interest.
What atmospheric signals should I follow when trading tornado contracts?
The most relevant signals are CAPE (Convective Available Potential Energy), low-level and deep-layer wind shear forecasts, ENSO state (La Niña increases Great Plains tornado risk in spring), SPC Day 1 and Day 2 convective outlooks, and SPC Mesoscale Discussions during active setups. The SPC's weekly severe weather summaries give you the running count as the month progresses.
What is the minimum to start trading tornado prediction market contracts?
Minimum deposits are $10 at Kalshi, OG, and Crypto.com. At Polymarket's international platform, a USDC transfer is required with a practical minimum of around $20 via card. Individual contracts can cost as little as $0.01.
