The prophecy speaks of a time in the future where, due to reasons not yet revealed (perhaps global disasters, a global economic collapse, EMP/CME, etc) people all over the nation will be living without any form of electricity, heat, water, etc.  Basically it's a massive grid down scenario or perhaps something else that takes away the normal creature comforts we've all become accustomed to.  However, in the midst of this, God will miraculously provide food, water, heat and other necessities to born again believers during what I believe is the Tribulation.  There's several ways the events of this prophecy are described, including people praying over empty plates after which they're filled with food, God miraculously heating homes in the middle of winter even though there's no viable source of heat in the house, etc.

This prophecy, while modern in nature, has some very strong biblical support in the fact that similar events have happened in the past.  This includes the feeding of the Israelites in the desert, the feeding of Elijah, the feeding of the widow who took in Elijah, Jesus's own feeding of the 5000 and 4000, the miraculous provision of fish after His resurrection, and so on.  Therefore this does have some good biblical backing.  As for all of the known sources, I've seen several prior to this, but never thought to write them down or track them until recently.  The ones I have linked here are just for starters to get things rolling, but as I find the more detailed entires I've seen before, I'll post them here.

Also, this prophecy goes both along with, as well as above and beyond the promises made in Philippians 4:19 as these will be miraculous supernatural provisions to believers.  Now that's not saying the verse doesn't cover that.  What I'm saying is that, whereas its typical application is day to day needs, it also covers supernatural provision where normal mechanisms of blessing and supply (job, grocery store, food bank, giving, etc) either aren't in play or are no longer possible due to extenuating circumstances.  Thus these modern prophecies are more or less an extension of that promise made in Philippians 4:19, perhaps to reassure those left behind that, even in their extreme and perilous situation, God will STILL provide all their needs, no matter what, even if it has to be done supernaturally.