When Alan and the family are down the river at night, when it's raining like crazy, he uses the satellite phone to call Elly. It's really dark where Alan is calling. Well, where Elly is, it's during the day, and it's very bright. Regardless of where Elly is in the US (except possibly Alaska and Hawaii, although judging by her home, I doubt it), there are no dramatic time differences between where Alan is (near Costa Rica) and where she is.