Polymarket Weather Trader

Trade temperature markets on Polymarket using NOAA forecast data.

This is a template. The default signal is NOAA temperature forecasts — remix it with other weather APIs, different forecast models, or additional market types (precipitation, wind, etc.). The skill handles the plumbing (market discovery, NOAA parsing, trade execution, safeguards). Your agent provides the alpha.

Risk Management

Weather market outcomes are discrete: a temperature bucket ("34-35°F") either matches the actual high on resolution day or it doesn't. The strategy works when the NOAA forecast is more accurate than what the market has priced in.

Test before going live. The skill defaults to paper mode — trades are simulated at real market prices while your USDC stays untouched. Pass

--live

when you're ready. For a fully virtual sandbox, switch the SDK venue to

sim

for $SIM-denominated paper trading.

Simmer's server-side risk monitor handles stop-loss and take-profit automatically. Defaults (editable at

simmer.markets/dashboard → Settings → Auto Risk Monitor

Stop-loss at 20% drawdown from entry
Take-profit at 50% price

External wallet users: monitors emit alerts via the briefing endpoint — your agent must be running for sells to execute. Managed wallet users: server executes directly.

You can override defaults per-skill in the dashboard.

When to Use This Skill

Use this skill when the user wants to:

Trade weather markets automatically
Set up gopfan2-style temperature trading
Buy low on weather predictions
Check their weather trading positions
Configure trading thresholds or locations

What's New in v1.18.1

SKILL.md rewrite highlighting paper mode (default) and $SIM venue as first-class ways to test the skill before going live.

What's New in v1.18.0

Autotune config defaults aligned with documented defaults (entry 0.15, exit 0.45, max position $2, sizing 5%).
```
SIMMER_WEATHER_BINARY_ONLY
```
is now an autotune-exposed tunable — set
```
true
```
to trade only binary yes/no weather markets.
Autotune ranges for
```
max_position_usd
```
and
```
sizing_pct
```
tuned to match typical use.
Risk management documentation clarified: auto-risk monitor handles stop-loss/take-profit at the user level.

What's New in v1.17.0

Volatility Targeting: Dynamic position sizing based on realized market volatility. Uses EWMA of log returns from price history. High vol → smaller positions, low vol → larger positions. Enable with
```
--vol-targeting
```
flag or
```
SIMMER_WEATHER_VOL_TARGETING=true
```
.
- ```
SIMMER_WEATHER_TARGET_VOL
```
  — target annualized vol (default 20%)
- ```
SIMMER_WEATHER_VOL_MAX_LEVERAGE
```
  — max scale-up multiplier (default 2.0x)
- ```
SIMMER_WEATHER_VOL_MIN_ALLOC
```
  — min allocation floor (default 20%)
- ```
SIMMER_WEATHER_VOL_SPAN
```
  — EWMA responsiveness (default 10)

v1.14.0

Fixed env var names to match autotune registry (old names still work as aliases):

SIMMER_WEATHER_ENTRY

→

SIMMER_WEATHER_ENTRY_THRESHOLD

SIMMER_WEATHER_EXIT

→

SIMMER_WEATHER_EXIT_THRESHOLD

SIMMER_WEATHER_MAX_POSITION

→

SIMMER_WEATHER_MAX_POSITION_USD

SIMMER_WEATHER_MAX_TRADES

→

SIMMER_WEATHER_MAX_TRADES_PER_RUN

New tunable:
SIMMER_WEATHER_SLIPPAGE_MAX
— adjustable slippage safeguard (default 15%). Set higher for research mode on illiquid markets.
New tunable:
SIMMER_WEATHER_MIN_LIQUIDITY
— skip markets with liquidity below this USD threshold (default 0 = disabled). Pre-filters thin markets before execution.

SIMMER_WEATHER_LOCATIONS
and
SIMMER_WEATHER_BINARY_ONLY
now exposed as autotune tunables.

v1.13.0

Binary Only Mode: New
```
SIMMER_WEATHER_BINARY_ONLY
```
config to skip range-bucket events (e.g., "NYC 34-35°F") and only trade binary yes/no weather markets

v1.2.0

Max Trades Per Run: New
```
SIMMER_WEATHER_MAX_TRADES
```
config to limit trades per scan cycle (default: 5)

v1.1.1

Status Script: New
```
scripts/status.py
```
for quick balance and position checks
API Reference: Added Quick Commands section with API endpoints

v1.1.0

Source Tagging: All trades tagged with
```
sdk:weather
```
for portfolio tracking
Smart Sizing: Position sizing based on available balance (
```
--smart-sizing
```
)
Context Safeguards: Checks for flip-flop warnings, slippage, time decay
Price Trend Detection: Detects recent price drops for stronger signals

Setup Flow

When user asks to install or configure this skill:

Install the Simmer SDK

pip install simmer-sdk

Ask for Simmer API key
- They can get it from simmer.markets/dashboard → SDK tab
- Store in environment as
```
SIMMER_API_KEY
```
Ask for wallet private key (required for live trading)
- This is the private key for their Polymarket wallet (the wallet that holds USDC)
- Store in environment as
```
WALLET_PRIVATE_KEY
```
- The SDK uses this to sign orders client-side automatically — no manual signing needed
Ask about settings (or confirm defaults)
- Entry threshold: When to buy (default 15¢)
- Exit threshold: When to sell (default 45¢)
- Max position: Amount per trade (default $2.00)
- Locations: Which cities to trade (default NYC)
Save settings to environment variables
Set up cron (disabled by default — user must enable scheduling)

Configuration

Setting	Environment Variable	Default	Description
Entry threshold	`SIMMER_WEATHER_ENTRY_THRESHOLD`	0.15	Buy when price below this
Exit threshold	`SIMMER_WEATHER_EXIT_THRESHOLD`	0.45	Sell when price above this
Max position	`SIMMER_WEATHER_MAX_POSITION_USD`	2.00	Maximum USD per trade
Max trades/run	`SIMMER_WEATHER_MAX_TRADES_PER_RUN`	5	Maximum trades per scan cycle
Locations	`SIMMER_WEATHER_LOCATIONS`	NYC	Comma-separated cities (NYC, Chicago, Seattle, Atlanta, Dallas, Miami)
Binary only	`SIMMER_WEATHER_BINARY_ONLY`	false	Skip range-bucket events (e.g., "34-35°F"), only trade binary yes/no markets
Smart sizing %	`SIMMER_WEATHER_SIZING_PCT`	0.05	% of balance per trade
Slippage max	`SIMMER_WEATHER_SLIPPAGE_MAX`	0.15	Skip trades with slippage above this (0.15 = 15%)
Min liquidity	`SIMMER_WEATHER_MIN_LIQUIDITY`	0	Skip markets with liquidity below this USD amount (0 = disabled)
Vol targeting	`SIMMER_WEATHER_VOL_TARGETING`	false	Enable volatility targeting for dynamic position sizing
Target vol	`SIMMER_WEATHER_TARGET_VOL`	0.20	Target annualized volatility (0.20 = 20%)
Vol max leverage	`SIMMER_WEATHER_VOL_MAX_LEVERAGE`	2.0	Max scale-up multiplier in calm markets
Vol min alloc	`SIMMER_WEATHER_VOL_MIN_ALLOC`	0.2	Min allocation floor in volatile markets (0.2 = 20%)
Vol EWMA span	`SIMMER_WEATHER_VOL_SPAN`	10	EWMA span for vol calculation (lower = more responsive)

Legacy env var aliases (still accepted for backwards compatibility):

SIMMER_WEATHER_ENTRY

SIMMER_WEATHER_EXIT

SIMMER_WEATHER_MAX_POSITION

SIMMER_WEATHER_MAX_TRADES

Supported locations: NYC, Chicago, Seattle, Atlanta, Dallas, Miami

Quick Commands

# Check account balance and positions
python scripts/status.py
Detailed position list

python scripts/status.py --positions

API Reference:

Base URL:
```
https://api.simmer.markets
```
Auth:
```
Authorization: Bearer $SIMMER_API_KEY
```
Portfolio:
```
GET /api/sdk/portfolio
```
Positions:
```
GET /api/sdk/positions
```

Running the Skill

# Dry run (default — shows opportunities, no trades)
python weather_trader.py
Execute real trades
python weather_trader.py --live
With smart position sizing (uses portfolio balance)
python weather_trader.py --live --smart-sizing
Check positions only
python weather_trader.py --positions
View config
python weather_trader.py --config
Disable safeguards (not recommended)
python weather_trader.py --no-safeguards
Disable trend detection
python weather_trader.py --no-trends
Enable volatility targeting (dynamic sizing based on market vol)
python weather_trader.py --live --smart-sizing --vol-targeting
Quiet mode — only output on trades/errors (ideal for high-frequency runs)
python weather_trader.py --live --quiet
Combine: frequent scanning, minimal noise

python weather_trader.py --live --smart-sizing --quiet

How It Works

Each cycle the script:

Fetches active weather markets from Simmer API
Groups markets by event (each temperature day is one event)
Parses event names to get location and date
Fetches NOAA forecast for that location/date
Finds the temperature bucket that matches the forecast
Safeguards: Checks context for flip-flop warnings, slippage, time decay
Trend Detection: Looks for recent price drops (stronger buy signal)
Entry: If bucket price < threshold and safeguards pass → BUY
Exit: Checks open positions, sells if price > exit threshold
Tagging: All trades tagged with
```
sdk:weather
```
for tracking

Smart Sizing

With

--smart-sizing

, position size is calculated as:

5% of available USDC balance (configurable via
```
SIMMER_WEATHER_SIZING_PCT
```
)
Capped at max position setting ($2.00 default)
Falls back to fixed size if portfolio unavailable

This prevents over-deployment and scales with your account size.

Volatility Targeting

With

--vol-targeting

, position sizes are dynamically adjusted based on realized market volatility:

position_size = base_size × clamp(target_vol / realized_vol, min_alloc, max_leverage)

High volatility (price swinging): positions scale down → less risk
Low volatility (price stable): positions scale up → more alpha capture
Falls back to base size if insufficient price history (< 15 data points)

Combines with smart sizing: first calculate base size from portfolio %, then apply the vol multiplier.

Safeguards

Before trading, the skill checks:

Flip-flop warning: Skips if you've been reversing too much
Slippage: Skips if estimated slippage > 15%
Time decay: Skips if market resolves in < 2 hours
Market status: Skips if market already resolved

Disable with

--no-safeguards

(not recommended).

Source Tagging

All trades are tagged with

source: "sdk:weather"

. This means:

Portfolio shows breakdown by strategy
Copytrading skill won't sell your weather positions
You can track weather P&L separately

Example Output

🌤️ Simmer Weather Trading Skill
==================================================
⚙️ Configuration:
Entry threshold: 15% (buy below this)
Exit threshold:  45% (sell above this)
Max position:    $2.00
Locations:       NYC
Smart sizing:    ✓ Enabled
Safeguards:      ✓ Enabled
Trend detection: ✓ Enabled
💰 Portfolio:
Balance: $150.00
Exposure: $45.00
Positions: 8
📍 NYC 2026-01-28 (high temp)
NOAA forecast: 34°F
Matching bucket: 34-35°F @ $0.12
💡 Smart sizing: $2.00 (capped at max position)
✅ Below threshold ($0.15) - BUY opportunity! 📉 (dropped 15% in 24h)
Executing trade...
✅ Bought 62.5 shares @ $0.12
📊 Summary:
Events scanned: 12
Entry opportunities: 1
Trades executed: 1

Troubleshooting

"Safeguard blocked: Severe flip-flop warning"

You've been changing direction too much on this market
Wait before trading again

"Slippage too high"

Market is illiquid, reduce position size or skip

"Resolves in Xh - too soon"

Market resolving soon, risk is elevated

"No weather markets found"

Weather markets may not be active (seasonal)

"External wallet requires a pre-signed order"

```
WALLET_PRIVATE_KEY
```
is not set in the environment
The SDK signs orders automatically when this env var is present — no manual signing code needed

Fix:

export WALLET_PRIVATE_KEY=0x<your-polymarket-wallet-private-key>

Do NOT attempt to sign orders manually or modify the skill code — the SDK handles it

"Balance shows $0 but I have funds on Polygon"

Polymarket V2 (live 2026-04-28) uses pUSD (PolyUSD, 1:1 backed by USDC.e). If your wallet holds USDC.e, migrate at simmer.markets/dashboard with one click (~30s)
If you bridged native USDC (Circle), swap to USDC.e first, then migrate to pUSD
Full migration guide: docs.simmer.markets/v2-migration

"API key invalid"

Get new key from simmer.markets/dashboard → SDK tab

Polymarket Weather Trader

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