I would say a slightly unhelpful comment by the FO.
But entirely prompted by bad CRM on the point of the skipper.
Capt should have asked the FO what his plan was for dealing with the weather. If the response was unsuitable (vague, unsafe or un commercial) the Captain would then be in a position to make sure the FO and he had the same mental picture of the various factors involved. You never know - sometimes the FO knows something the Captain hasn't realised - but on balance it is the Captains responsibility to overrule the FOs choice of flight path even though it is the FO's leg.
Instead, what the Captain did was blur the lines between the flight deck roles. Cartainly if I was the FO in that situation I would be identifying the possibility for confusion. I'd be thinking along the following lines:
"Was that a one off intervention? Am I responsible for the heading or has the Captain taken it over until further notice?"
Its just like basic training - "I have control / you have control" exists for a reason. Now the FO does not know who is responsible for the lateral flight path! Its bad CRM and bad captaincy.
Personally, I would probably (if I was FO) have said something like: "Will you be organising the weather avoidance or would you like me to deal with it from here?". Hopefully that would be a little less sulky / sarcastic and elicit a clear statement from the Captain about what he wants the FO to do.