Lightning impacts Southern Oregon and Northern California in many ways. First, it can have significant impacts on the landscape of Southern Oregon and Northern California, including the start of wildfires. Additionally, thunderstorms can bring damaging winds, hail, flooding rainfall, and impacts to roadways via downed trees and other hazards.  Last but not least, lightning alone poses a safety risk as humans are killed each year due to lightning. 

We at the National Weather Service Office in Medford have been mapping and studying lightning over Southern Oregon and Northern California since about 2015. We'll share some of the imagery we've created here, and hopefully it provides some actionable information for people in terms of where and when lightning is most/least common for Southern Oregon and Northern California. 

Below is a flash density map, showing where cloud to ground lightning flashes are most common across the forecast area.  Additionally, the bar chart shows how cloud to ground lightning flashes vary throughout the year across the forecast area.  There is a "spring spike" followed by multiple peaks in the summer.

Over 800 million cloud to ground lightning flashes were observed between 1988 and 2017 across the Continental US. We've visualized these flashes per hour per week of the year for all counties, fire weather zones, and airports in the Continental US, and we're excited to share this imagery with you! Each image really tells a story of thunderstorm activity for each geographic area.

Access heatmaps centered on Southern Oregon and Northern California.

Access heatmaps for entire Continental United States.

Here's a video that describes this service: 

This service is experimental, so we encourage feedback via the survey provided at the top of the map. The primary goals for this imagery are to better enable weather-related decisions and reduce risk for interests that are impacted by thunderstorms.

Note: imagery is not standardized per unit area (except for airports layer) and the intent of this first iteration of imagery isn't to compare geographic areas but instead to visualize when lightning is least/most likely per given geographic area.