There is a saying in Wisconsin that goes "If you don't like the weather in Wisconsin, wait five minutes; it'll change."
Some of you are now wondering why we stole your phrase. Or why you stole it from us. Or why we all stole it from Mark Twain, who in its original form was referring to New England.
Here's a basic fact of weather: it changes. All the time, everywhere. Even in places that have a pretty stable climate- San Francisco, perhaps- it still gets sunny and cloudy and rainy and foggy and the temperature does still fluctuate to some degree.
What appears to be the chief criteria for gaining this phrase is that the location has the following two weather phenomena:
1) Sometimes it rains.
2) But sometimes, it doesn't rain.
So let's just clear this up now. What follows is a list of every location I was able to track down that has used the magic words (or slightly altered the time period) to describe their area, in alphabetical order. This is absolutely an incomplete list. At some point I just had to stop.
Auckland, New Zealand
British Columbia, Canada
Little Rock, AR
Los Angeles, CA (with a 'drive five miles' variation)
Machu Picchu, Peru
Maritime Provinces, Canada
Nevada (someone has actually invoked this on Las Vegas, contrary to everything known to man about Las Vegas' actual climate, and gotten 3,483 likes on Facebook over it)
New Orleans, LA
Outer Banks, NC
Mitt Romney... no, he is not a location, but the joke's been used on him too, so in he goes
San Francisco, CA
If I have missed your home region and you have seen the phrase used as well... for God's sake, get a new saying.