The average temperature the first half of April in Fairbanks was10.8ºF. This is a remarkable 16.3 degrees below normal and the fourth coldest of record (second coldest in the WB/NWS era). The chart plots the mean temperature the first half of April and the 10-year running mean.
The 10 year running mean shows nicely that there has been little trend in April temperatures over the past 50 years except for the decade or so of warm Aprils in the 1990s. This year is a good example of an "outlier" that we have no reason to think is tied to a larger pattern (unlike say, Barrow temperatures in October).
Here's a link to the NWS Alaska Region Facebook graphic showing how the cold weather this month is distributed across Alaska. Northwest and Southeast Alaska have not been notably cold but in between it sure has been.