Narrative:

Departed miami runway 9L with large thunderstorm cell east of airport. Aircraft were making immediate left turns to the north. North of airport were numerous small cells that did not paint on radar and visually looked quite harmless. The aircraft was leveling off at 16000 ft. We entered an updraft that was quite violent. The autoplt disconnected and the aircraft was lifted to 16400 ft before I was able to recover. I used an almost full nose down correction with little effect. There was no turbulence, just tremendous uplift. I now have greater respect for small growing cells that do not paint on radar.

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Original NASA ASRS Text

Title: AFTER DEPARTING MIA, AN ACR CREW ENCOUNTERED SEVERE TURB IN AN AREA COVERED WITH SMALL WX CELLS.

Narrative: DEPARTED MIAMI RWY 9L WITH LARGE TSTM CELL E OF ARPT. ACFT WERE MAKING IMMEDIATE L TURNS TO THE N. N OF ARPT WERE NUMEROUS SMALL CELLS THAT DID NOT PAINT ON RADAR AND VISUALLY LOOKED QUITE HARMLESS. THE ACFT WAS LEVELING OFF AT 16000 FT. WE ENTERED AN UPDRAFT THAT WAS QUITE VIOLENT. THE AUTOPLT DISCONNECTED AND THE ACFT WAS LIFTED TO 16400 FT BEFORE I WAS ABLE TO RECOVER. I USED AN ALMOST FULL NOSE DOWN CORRECTION WITH LITTLE EFFECT. THERE WAS NO TURB, JUST TREMENDOUS UPLIFT. I NOW HAVE GREATER RESPECT FOR SMALL GROWING CELLS THAT DO NOT PAINT ON RADAR.

Data retrieved from NASA's ASRS site as of July 2007 and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.