How about ColdSnap! Frost Alarm for Android ? ;-)

I ran into similar trouble and couldn't find anything that really worked...so I developed my own !

I'm afraid its only for Android Mobile phones, as that's the extent of my developer skills...

It just runs silently in the background until a temperature is forecast below a set level, then pops up a notification in the notification bar. It'll also restart if you restart the phone...so given we're now verging on summer, you can still intsall and forget about it for a few months without worrying that it'll still be checking in the background for that innevitable frost ! (or wierd freak of weather...who knows...)

https://market.android.com/details?i...=search_result

it's 99p so cheaper than a pack of Burpless Tasty

any feedback welcome.
Ant.