Atmospheric River in the Pacific Northwest and Northern Rockies this Weekend

A Pacific storm and atmospheric river will impact the Pacific Northwest states and northern Rockies this weekend, bringing locally heavy low elevations rain and heavy high elevation snow in the mountains. By Sunday over the Interior Northwest, rain combined with snowmelt will increase the risk of flood hazards. Flood Watches are in effect. Read More >

Lightning Potential Index Header Image

Using the weather.gov/gjt website, you can obtain forecast lightning information year-round. The Lightning Potential Index (LPI) provides graphical guidance for the potential of lightning over a 60 hour period. This looping product will update continuously on a 3 hourly basis as new computer model information becomes available. This information should be used for general planning purposes only and is provided for the National Weather Service Grand Junction area of responsibility (eastern Utah and western Colorado). You are urged to seek out the latest forecast information by visiting WFO Grand Junction. Please see our Lightning Safety Page for more information.

To access the LPI:

First, click on the ‘Forecasts’ section of our website (red arrow below). A drop-down menu will then appear. Click on the 7^th entry from the top (or 2^nd one from the bottom) called ‘Lightning Potential Index (red oval).

From there, you will see the following webpage:

From this page, you can loop the current forecast, stop the loop, and step through each image in the loop.

And at the bottom of the page (or right above this text) you will find the Color Key and Explanation section of the page (or the legend). Think of the LPI as a stop light; Green means go, Yellow exercise caution and Red means stop (or take the day off from climbing that 14er).

If you have any questions on how to use the Lightning Potential Index, don’t hesitate calling us at 970-243-7007 or email us at wxgjt@noaa.gov.

Follow us on X

Follow us on Facebook

Follow us on YouTube

GJT RSS Feed

Atmospheric River in the Pacific Northwest and Northern Rockies this Weekend

Lightning Potential Index Tutorial