Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument; Flight Crew Multiengine
Communication Breakdown; Situational Awareness
ATC Issue All Types; Deviation - Track / Heading All Types; Inflight Event / Encounter Loss Of Aircraft Control; Inflight Event / Encounter Weather / Turbulence
Flight Crew Regained Aircraft Control
Human Factors; Weather
Taking off out of MIA on WINCO2. Passing 4;000 feet (climbing to 16000 feet); vectored to 340 heading. Saw two large cells (tops to FL550) between my position and BORLE intersection. Cleared on heading 310; direct BORLE when able. I told the controller I wanted a heading of 350 to pass to the north of both cells. I was told 'No;' aircraft are getting through the gap between the two cells. Skirted the first cell to the south; but the gap had closed. Immediately got severe turbulence from the cell on the right. Turbulence was severe (off and on) for 2-3 minutes. Aircraft also had two distinct short periods of uncontrolled flight. First Officer was commanding a right hand turn in both instances and the aircraft turned left 45 degrees. No over speed; no G exceedance; no altitude deviations; no aircraft limitations exceeded. No injuries. Flight attendants were told to remain seated. After 3 minutes; the aircraft exited the cell and was VFR.This event occurred because MIA Departure was unwilling to let me head 350 as requested to miss all storms. I understand that FLL airspace is just to the north of MIA and leaving me on a 350 heading would conflict with arrivals into FLL is a concern. Telling me that aircraft are getting through the gap only works until it doesn't. For our flight; it did not work. Once we turned to a heading of 310; we were committed. There just is not a lot of room between where we were and BORLE.If the crew does not want to try to shoot a gap; another solution should have been offered. Once on the heading toward the storms; the aircraft was committed! Turning right 270 degrees and skirting the storms to the south should have been offered. Luckily; no one was hurt and no aircraft damage was noted.
A319 Captain reported asking for a turn out of weather; ATC said no; flight went through area of severe turbulence.