If it's been more than a year since that hose was replaced, then it'd be a good idea to get a new one. They disintegrate from the inside out, so anything happening on the outside like that is a sign it's about to split.
If one is about to split, you need to change ALL the hoses because they're just as old as the problem hose. The lower radiator hose, the bypass hose, the heater hose from the water pump and the two twisties at the firewall need to be changed.
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