Narrative:

Climbing out of austin with the controller's report of thunderstorms to the south and level 3 activity at 2 O'clock position and 10 mi, we emerged from a haze layer to a boxed canyon arrangement of cells with tops a few thousand ft above our altitude. They had not showed up on radar. We were level at 12000 ft and immediately asked for higher. Clearance was denied and we were directed to turn right when able and to change frequencys to ZHU. We could not wait. I declared an emergency and started a climb into airspace that appeared clear visually and on TCASII. We established communication with center as we passed 13000 ft. He cleared us to FL230. Even though the first controller sounded adamant about not climbing, in my opinion, if we had waited to change frequencys, establish contact, and get permission to climb, we would have experienced -- at a minimum -- moderate turbulence, and probably severe. I cannot be certain, because I do not remember ever flying into anything that looked like that. I saw no way out, except to climb. I regret that we found ourselves in a situation that required rejection of controller instructions to resolve. Supplemental information from acn 431589: we took off from aus with a clearance to 4000 ft. After contacting aus departure, we were issued a series of heading changes towards heading 250 degrees and issued a climb clearance to 12000 ft. I had responded to the frequency change and was about to switch frequencys when the captain requested to climb from aus approach. The controller responded with, 'say again' to which the captain responded, 'we are climbing for WX.' the controller responded by saying, 'maintain 12000 ft,' to which the captain said, 'we are declaring an emergency and climbing.' aus approach then said, 'ok' and told us to contact houston. After a couple of queries from ZHU about the nature of the emergency, which the captain stated was his grave concern about the WX immediately around us, the emergency was terminated and the flight continued on uneventfully.

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Original NASA ASRS Text

Title: MD80 CREW DECLARED EMER AND CLBED ABOVE ASSIGNED ALT TO AVOID TSTMS.

Narrative: CLBING OUT OF AUSTIN WITH THE CTLR'S RPT OF TSTMS TO THE S AND LEVEL 3 ACTIVITY AT 2 O'CLOCK POS AND 10 MI, WE EMERGED FROM A HAZE LAYER TO A BOXED CANYON ARRANGEMENT OF CELLS WITH TOPS A FEW THOUSAND FT ABOVE OUR ALT. THEY HAD NOT SHOWED UP ON RADAR. WE WERE LEVEL AT 12000 FT AND IMMEDIATELY ASKED FOR HIGHER. CLRNC WAS DENIED AND WE WERE DIRECTED TO TURN R WHEN ABLE AND TO CHANGE FREQS TO ZHU. WE COULD NOT WAIT. I DECLARED AN EMER AND STARTED A CLB INTO AIRSPACE THAT APPEARED CLR VISUALLY AND ON TCASII. WE ESTABLISHED COM WITH CTR AS WE PASSED 13000 FT. HE CLRED US TO FL230. EVEN THOUGH THE FIRST CTLR SOUNDED ADAMANT ABOUT NOT CLBING, IN MY OPINION, IF WE HAD WAITED TO CHANGE FREQS, ESTABLISH CONTACT, AND GET PERMISSION TO CLB, WE WOULD HAVE EXPERIENCED -- AT A MINIMUM -- MODERATE TURB, AND PROBABLY SEVERE. I CANNOT BE CERTAIN, BECAUSE I DO NOT REMEMBER EVER FLYING INTO ANYTHING THAT LOOKED LIKE THAT. I SAW NO WAY OUT, EXCEPT TO CLB. I REGRET THAT WE FOUND OURSELVES IN A SIT THAT REQUIRED REJECTION OF CTLR INSTRUCTIONS TO RESOLVE. SUPPLEMENTAL INFO FROM ACN 431589: WE TOOK OFF FROM AUS WITH A CLRNC TO 4000 FT. AFTER CONTACTING AUS DEP, WE WERE ISSUED A SERIES OF HDG CHANGES TOWARDS HDG 250 DEGS AND ISSUED A CLB CLRNC TO 12000 FT. I HAD RESPONDED TO THE FREQ CHANGE AND WAS ABOUT TO SWITCH FREQS WHEN THE CAPT REQUESTED TO CLB FROM AUS APCH. THE CTLR RESPONDED WITH, 'SAY AGAIN' TO WHICH THE CAPT RESPONDED, 'WE ARE CLBING FOR WX.' THE CTLR RESPONDED BY SAYING, 'MAINTAIN 12000 FT,' TO WHICH THE CAPT SAID, 'WE ARE DECLARING AN EMER AND CLBING.' AUS APCH THEN SAID, 'OK' AND TOLD US TO CONTACT HOUSTON. AFTER A COUPLE OF QUERIES FROM ZHU ABOUT THE NATURE OF THE EMER, WHICH THE CAPT STATED WAS HIS GRAVE CONCERN ABOUT THE WX IMMEDIATELY AROUND US, THE EMER WAS TERMINATED AND THE FLT CONTINUED ON UNEVENTFULLY.

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.