CRJ-900 First Officer reported encountering moderate turbulence and wind shear at FL330 that resulted in large airspeed variations; including a stall warning.

Narrative

Enroute from ZZZ to ZZZ1 Day 0; we immediately began the climb out portion of the flight with radar vectors and deviations for Cumulus buildups and weather in the area. Reaching our cruising altitude of 33;000. We continued with vectors around buildups that we could see visually as well as with the aircraft radar and EFB weather app. We requested a climb to 35;000 to attempt to top out a build up. Reaching 35;000 it was evident we would not out climb it. The onboard weather radar showed no significant precipitation and marking only light green 'color' projections in the buildup. The EFB app also did not show significant turbulence in it when refreshed on the app. I did have issues with wifi connection with the aircraft and EFB as it was often slow to refresh. I still checked mine before continuing on course through. There was all no warnings from ATC about ride conditions on our path. Pre-emptively we called the flight attendants and told them of possible rough air coming up so to take their seats in the cabin. The buildup was wide and through discussion with the Captain we evaluated the best solution. With our combination of evidence from the radar; EFB; and visual evaluation of the path it was concurred to continue on the path we were on that would go through a portion of the visual cloud buildup. From my seat the build up seemed to be in its dissipation stage and had a large amount of blowoff at the tops. It did not seem we would be going through such a aggressively turbulent area but we did expect rough air. When we initially entered IMC we entered a portion of moderate turbulence and we reported to ATC. We were changed to the next sector and issued a descent instruction to FL330 and request a turn to exit the area. As we entered this descent the turbulent air increased with more aggressive jolts on the aircraft. The autopilot disconnected abruptly and the airspeed entered a large increase then decrease in speed/trend. With the movement of the aircraft I had difficulty reading clearly the specific data on the PFD (Primary Flight Display). The Captain was Pilot Flying and was hands on the controls to stabilize the aircraft. I look up at the Continuous ignition switch/light and see it turning on/off. I press in the button to keep it on. I knew the continuous ignition coming on was the first indication of an impending stall. I see the airspeed is still oscillating. The pitch remains down in the descent as the Captain is at the controls. After a few more seconds we exit the cloud layer and are back in Visual conditions and the turbulence stops. We re engage the autopilot and finish the descent. We then receive reports from ATC and Dispatcher via ACARS about the area of turbulence. I call the flight attendants to check on the condition of the cabin and passengers. There was no injury or damage. Debriefing in the air; the Captain and I were both surprised at what had happened. Those conditions were not expected to be as rough as they were. He mentioned to me that during the recovery process in manual controls he felt there may have been a possible stick shaker which he respected of the aircraft. I did not have my hands on the controls and could not confirm that. All I noticed was the continuous ignition turning on on its own. We each had not experienced turbulence strong enough to disconnect the autopilot and were surprised. It also was not the worst turbulence either of us had felt in the aircraft before.We reviewed the required reportable events list in the FOM and did not see a report for what had just happened. I personally did not expect the details to be as they were until receiving a call from the FOQA department.Today; Day 2 I received a call from the FOQA department in which i was informed we actually encountered a stick shaker and pusher event on the aircraft. I was surprised and did not realize such a serious event occurred. Since we were already in a descent and going through turbulence I could not identify thestick pusher activating and did not recognize the red stall warning indications going off. My only reference was the continuous ignition light as a caution to us. I did not physically have my hands on the controls of the aircraft and did not feel such movement of the pusher activation. Going through the FOQA data; an 8 knot headwind turned into a 37 knot tailwind totaling a 45 knot airspeed loss. The initial pitch attitude on the descent was 2 degrees and went down to negative 6.59 degrees (a 8 degree swing in pitch). When the pusher occurred the load factor went from 1.4 g's to .17 g's. Airspeed in knots went from 244 to 216 knots (mach data not available to me yet). This was 15 knots below the buffet Vmd.Cause: The weather conditions were much more aggressive than indicated. A large wind shift to a tailwind decreased aircraft performance bringing airspeed below VMD activating the stick shaker and pusher on the aircraft. Our expectation of the conditions was evidently wrong and resulted in the uncommanded aircraft state. The data from our weather radar; EFB; ATC; and our visual judgement was not sufficient to deter us from the area we ultimately decided to go through. In the duration of our 5 day trip together we dealt with a lot of thunderstorm avoidance even holding and a diversion. Our communication about weather was open in the flight deck and discussed thoroughly especially in the moments leading up to this event. We started with the possibility of out climbing it and continued with deviations. It was a decision made through positive CRM and evaluating all of our options. Suggestions: This event was a learning moment in the areas of Weather; decision making; CRM; and aircraft systems.I expected the aircraft autopilot had disconnected because the turbulence was greater than the autopilot could maintain control over; when in fact it disconnected as the initial response to the stick shaker activating.In the flight deck we do always do our best to avoid dangerous and uncomfortable weather conditions. Throughout our 5 day trip(this flight was the last leg of our trip) we encountered and navigated around several thunderstorms one flight which ended up in a diversion because we made the mutual decision attempting an approach at the field in ZZZ2 would not be a good decision due to the risk as well as fuel conditions. This is to say we had numerous discussions about weather and had an open communication with each other and did what we could with the information we had to make the best possible decision.The moving radar feature on the Weather app would surely be a benefit to have along with more consistent wifi with the aircraft. While that is just a secondary resource it is still a valuable resource when it come to decision making.I definitely will use the experience from this event to make decisions in the future in regarding to weather avoidance as well as undesired aircraft states. Again; with the information we had we made the decision we judged would be safest. Our training on stall recovery and turbulent mitigation was evident especially as the Captain remained in control of the aircraft on the descent.