Date: 201810
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: Marginal
Weather elements / visibility: Thunderstorm; Turbulence; Windshear
Light: Daylight
Aircraft: Regional Jet 900 (CRJ900)
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach; Landing
Airspace: Class C ZZZ
ATC / advisory: Tower ZZZ
Reporter organization: Air Carrier
Reporter function: Pilot Flying; Captain
Reporter qualification: Flight Crew Instrument; Flight Crew Air Transport Pilot (ATP); Flight Crew Multiengine
Human factors: Workload; Situational Awareness
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Deviation / Discrepancy - Procedural Published Material / Policy; Flight Deck / Cabin / Aircraft Event Illness / Injury; Inflight Event / Encounter Weather / Turbulence; Inflight Event / Encounter Unstabilized Approach
Detector: Automation Aircraft Other Automation; Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Provided Assistance; Flight Crew Requested ATC Assistance / Clarification; Flight Crew Took Evasive Action; Flight Crew Exited Penetrated Airspace; Flight Crew Executed Go Around / Missed Approach; Flight Crew Diverted; Flight Crew FLC complied w / Automation / Advisory
Contributing factors: Human Factors; Weather
Primary problem: Weather

Narrative: Encountered windshear inside the final approach fix to land XXR at ZZZ. Upon windshear warning I advanced full power and followed FD escape guidance; the FO/PM (First Officer/ Pilot Monitoring) advised tower we are going missed due to windshear. Once clear of the windshear we cleaned up the aircraft and asked for delay vectors to remain in the area as the weather may be clearing quicker and we had sufficient fuel to hold. In the moments following; we received a call from the FA (Flight Attendant) and were told that she felt ill and there were many passengers that were feeling sick due to the turbulence. During this call; another aircraft had gone missed due to the same windshear. I made the decision to divert to our filed alternate due to the safety and consideration of the passengers and crew on board. We would not put them through the same approach and more than likely receive the same result. Dispatch; ATC; the flight attendants and passengers were informed of the decision to divert. We sent a message to Dispatch asking to have medics standing by as a precaution for the passengers who had felt ill; this was also forwarded by me to ATC. No emergency was declared. Landed ZZZ1 without incident and medical personnel met the aircraft at the jet bridge; walked down the aisle and ensured each passenger was well. All were in good health and happy to disembark. We were delayed 2.5 hours on the ground out of [our departure field] and rerouted/refiled at 8000 feet. This added time and our original weather window was closing. I had asked for maximum fuel on board in anticipation of weather and ground delays being an issue. All these elements were taken into consideration and added to our plan to be on the lookout for sporadic airspeed deviations and review windshear escape maneuvers; go-around procedures; crosswind limitations; diversion/hold procedures and were all briefed.


Second narrative: [Report narrative contained no additional information.]


Synopsis: CRJ-900 flight crew reported a windshear event on final approach required an escape maneuver; followed by a diversion.