I've been using WeatherPop (Advanced) for a very long time.

It's really quite helpful/useful.

The problem is, there's some sort of bug in it that causes it to crash and disappear from the menu-bar. The programmer cannot seem to nail this problem down, as it's been reported by many users for quite a few versions now.

on idle
	tell application "System Events" to get name of every process
	if the result does not contain "WeatherPopApp" then
		tell application "WeatherPop" to launch
	end if
	return 900 -- checks every 15 minutes adjust to suit your needs
end idle

tell application "System Events"
	if not (exists process "WeatherPopApp") then
		tell application "WeatherPopApp"
			activate
		end tell
	end if
end tell