Flight Crew Air Transport Pilot (ATP)
Flight Deck / Cabin / Aircraft Event Illness / Injury; Inflight Event / Encounter Weather / Turbulence
Flight Crew Diverted; General Physical Injury / Incapacitation
Company Policy; Weather
In cruise flight at FL290 as we approached 50 West we detected weather along our course. Deviated 25nm left of course to avoid the weather and began a turn back on course when we detected additional weather ahead. We returned to our 25nm offset. Throughout we were in and out of cloud layers with light chop and had the seat belt sign on due to this. We briefly broke out of the layer to see what appeared to be a hole in the weather as illuminated by the full moon. We quickly realized it was actually a buildup even though it did not appear on our radar. The First Officer (Pilot Flying) began an immediate turn to the left to avoid the buildup. The aircraft briefly entered the cloud and encountered two jolts each lasting two to three seconds. We then emerged again into clear air between the layers. We received reports from the cabin of injuries and began to assess the situation that led to our decision to divert.  We requested clearance to ZZZZ as well as a climb to FL340 to climb above the weather.  Our landing in ZZZZ an hour later was uneventful. Paramedics met the aircraft to tend to the injured. The emergency responders; ZZZZ station and airport personnel were all exceptional in their support.
[Report narrative contained no additional information.]
Air carrier flight crew and a Flight Attendant reported diverting to a nearby alternate after several injuries resulted from a turbulence encounter.