Water coming in under new wooden door

It sounds like water could be tracking back underneath the threshold, **if there is one**, particularly as it only happens during heavy or wind-driven rain. Water can run down the door and, with the wind and heavy rain, work its way back underneath the timber threshold and onto the floor. As it’s a timber door and surround, it’s difficult to say for certain without seeing it. Sealing around the outside of the frame won’t necessarily stop water getting underneath if the issue is with how the threshold or bottom of the frame has been fitted and sealed. I’d have a close look at the bottom of the door, threshold (if fitted), and how the water is being directed away from the entrance.