In my opinion, it was the cold front that moved in. Water temps have remained pretty stable in the 50-53* range for the last 3 to 4 weeks. Stable water temps in the early spring promote bass activity. The bass bite was really good last week for a couple of reasons, #1 being the stable water temps, and #2 the stained water color that is clearing up.
Obviously there was no bite going on after the big rains hit which confused the bass with the high water levels, and the super dirty stained water, but............this stained water helped turn the bite on last week because the bass haven't been feeding very well. If I can't see my 5" grub, 6" below the surface, neither can the bass. Those bass didn't get to feed very well, if at all, for a good week or more after the heavy rains. Now that the lake has started to clear up, and the bass have adjusted to the higher water levels, they where hungry !
Early spring cold fronts shut down the bite more so then any other time of the year, once again imho.
This dirty water color is going to make for some killer fishing within the next week or two as is continues to clear up. There's a boat load of hungry fish out there looking for an easy, flashy BIG meal