Horses.   All day grass turnout.   Summer weather.   Thunderstorms.   Keeping safe.   That pretty much sums up summer time horse turnout management.   :-)
Most of our weather comes from the west, allowing us to see it approaching if we happen to be looking out the kitchen window.   However, if we're sitting at a computer, radar is our friend.
My favorite weather radar site is this one from Radar.Weather.Gov and allows me to view weather coming from all directions via the Adjacent Radars arrows.
I first learned about this site when a colleague at Sun Microsystems emailed out a warning to everyone in the Nashua office about a strong front speeding its way to New Hampshire in July 2005.   Thanks, Eric!
The storm of July 2005 was quite intense, rather terrifying, and caused a lot of damage including shearing many of our tallest trees and washing out the entrance to our driveway, as shown in this photo.   While we have not seen a storm as strong as that since, we still listen for rumbles of thunder, keep an eye on the skies and watch the radar whenever thunderstorm alerts are posted.