A CRJ700 First Officer reported that the Captain flying temporarily lost control during landing in a strong crosswind resulting in a wingtip strike.

Narrative

While on arrival into ZZZ; with current ATIS winds and punching in the landing data; the CA and I have determined that we are going to land RWY XX; as the landing data for XY would only work with bleeds off; APU off; no AI (Anti-Ice); and thrust reverser credit. The CA was PF. As we are on the ILS XX; we hear Tower give winds 310@19g39. These are more aligned with Runway XX than the ATIS said; however the gust factor was much much stronger. The CA left the autopilot engaged during the approach until about 300'. During this approach; I found zero reason to call a go around. After disconnecting the AP (Autopilot); I noticed the CA struggled to maintain wind correction and was making big thrust changes. CA seemed to overcorrect; then undercorrect; and overcorrect again till landing. The approach was stable; allowing for transitory increases in airspeed due to gusts. Over the threshold; she actually was looking set up for success and found best yoke correction. However; at the 30' aural call; she swung in rudder entirely too much; too fast; and too soon. This caused the plane to drift right of centerline. The CAs correction to this was to use too much aileron; added with what felt like a 40 knot gust; led to the wingtip striking; and landing well off centerline (still on the runway boundaries). About 1-2 seconds before making main wheel contact; I saw the Captain release the thrust lever; and had both hands on the yoke. This led me to raising my hands towards thrust levers as protection for a potential balked landing. After landing; Tower asked if we were alright; and to contact Ground. This; along with visibly seeing the damage to the aircraft during my post flight walk around; confirmed that we made ground contact with the slat leading edge/wingtip of the aircraft.Cause: Poor crosswind correction and failure to maintain aircraft control in the last 10-20 feet of flare. Failure to call balked landing by me (PM).Suggestion: Call for balked landing/ go around at first instinct and that low that the PF has poor crosswind control.