Widebody; Low Wing; 2 Turbojet Eng
Flight Crew Last 90 Days 240; Flight Crew Total 24000; Flight Crew Type 810
Aircraft Equipment Problem Less Severe; Deviation / Discrepancy - Procedural Published Material / Policy; Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural MEL / CDL; Inflight Event / Encounter Weather / Turbulence
Flight Crew Became Reoriented; Flight Crew Returned To Clearance; Flight Crew Took Evasive Action
Weather; Procedure; Airspace Structure; Aircraft
We [were] dispatched in an aircraft that had two placards: MEL's limiting the aircraft to FL 350 due to L1 Cabin Air Compressor.  Enroute we were assigned FL350 which put us barely above thunderstorms. We received from dispatch a report for moderate turbulence from FL 290-340; and aircraft lower than us were complaining of bad rides; including moderate turbulence.We were then given the choice of FL310 or FL390 to pass ZZZZs ADIZ. Anything lower than our altitude would have put us in immediate danger of embedded thunderstorms; with no clear and safe deviation path around them. For safety reasons we elected to climb to FL390 for a short time; thereby exceeding maximum placarded altitude of 350. Upon clearing the thunderstorms we descended back to FL350. We had a safe and smooth ride; and no reports of any abnormal conditions in the crew rest areas.
[Report narrative contained no additional information.]
A B787 flight crew reported transiting China and approaching Korea with imminent weather was restricted to FL350 because a cabin pressurization compressor was MELd. The crew elected to temporarily climb to FL390 over the weather.