Threshold Weather Data Methodology

A clear explanation of how Threshold sources, analyzes, and evaluates weather data for event planning decisions.

1. How Threshold Chooses Weather Data

Forecast vs. Historical Context

Threshold uses different data sources depending on how far away your event is.

Events within the next 10 days

• Threshold displays weather forecast data for your event's exact location and date.

Events beyond 10 days

• Threshold displays historical climatological data, calculated using a 15-year average for your event's location.

This approach ensures you always see the most reliable information available — forecasts when they are dependable, and historical patterns when long-range forecasts are not.

2. Weather Limits You Control

Threshold allows you to define what conditions are acceptable for your event.

You can set custom limits for:

• Maximum wind speed
• Maximum chance of precipitation
• Maximum rainfall amount
• Minimum temperature
• Maximum temperature

Threshold continuously evaluates weather data against your limits, rather than applying generic or fixed thresholds.

3. Event Status Logic

Each event is assigned one of three statuses based on your defined limits.

No-Go

An event is marked No-Go if any weather value:

• Exceeds your maximum limits (wind speed, precipitation chance, rainfall amount, or maximum temperature), or
• Falls below your minimum temperature limit

This logic applies to both forecast data and climatological data, depending on the event date.

Risk

An event is marked Risk when conditions are approaching your limits:

• Wind speed or precipitation chance: Within 20% of your maximum limit
• Rainfall amount or maximum temperature: Within 10% of your maximum limit
• Minimum temperature: Within 10% above your minimum temperature limit

Risk indicates that conditions are close enough to warrant attention, even if limits have not yet been exceeded.

Go

An event is marked Go when all weather values are comfortably within your defined limits.

4. How Climatological Data Is Calculated

For events occurring more than 10 days in the future, Threshold analyzes 15 years of historical weather data for the event's location.

The calculation method depends on the type of weather limit.

Temperature

• Uses a month, day, and hour match across the past 15 years
• Calculates the average of the 15 historical hourly temperatures
• Displays the resulting average value

Wind

• Uses a month and day match across the past 15 years
• Identifies the maximum wind gust for that day in each year
• Calculates the average of those 15 daily maximum gusts

Rainfall Amount

• Uses a month and day match across the past 15 years
• Collects the rainfall total for each of the 15 days
• Displays the average rainfall amount

Chance of Precipitation

• Uses a month and day match across the past 15 years
• Reviews each year to determine whether measurable rainfall (greater than 0.01 inches) occurred on that day
• Calculates the average probability of precipitation based on how often measurable rainfall occurred over the 15-year period

5. How Forecast Data Is Used

For events occurring within the next 10 days, Threshold displays weather forecast data based on the event's location and date.

Forecast data reflects current conditions and is updated as new information becomes available.

6. Why Threshold Uses This Approach

Weather forecasts are most accurate in the short term. For longer-term planning, historical patterns provide a more reliable foundation.

Threshold combines both approaches so you can:

• Make confident decisions today
• Plan responsibly for events weeks or months in advance

Threshold is designed as a decision-support tool and should be used alongside professional judgment.