Update: The line weakened considerably and is now no longer severe.
A destructive line of thunderstorms is moving across northern Utah this evening, producing 70 to 80 MPH winds, intense lightning, and very heavy rainfall as it continues east towards the I-15 corridor. 78 MPH winds were reported as this storm moved through parts of NW Utah a little while ago.
Even if there aren't any storms in Salt Lake City, there could be a gust front/outflow boundary/line of winds moving in conjunction with the storms.
And here's the wind velocity (in MPH) as of the same time:
If you live in or around Salt Lake City, make sure you secure anything loose (lawn furniture, plants, decorations, whatever) that could blow around once the storms hit. Stay away from the windows, don't go outside during the storm, and make sure you move away from any tall trees or otherwise unstable structures when the storms do hit.
You can keep track of the storms yourself by using this radar from Wunderground.