Narrative:

Cruise flight about midway observed line of thunderstorms developing and closing in approximately along a north/south line. Our route was through the line of thunderstorm. Approximately 120 mi prior advised flight attendants that they should plan to be seated and equipment stowed in 15-20 mins. Approximately 40-50 mi prior to thunderstorms; requested a deviation to the 'right.' ATC cleared us to a 180 degree heading. It appeared this would not be quite enough. To make an end run around what appeared to be the open area and also the upwind (85 KTS) side we requested a heading of 190 degrees. Controller advised unable; he would be descending us and then turning us. As we got closer; controller wanted us to turn left (east) through line of thunderstorms. We replied unable but we needed to turn further right. At a particular point in time; it seemed we could make a left turn and get between some large cumulo nimbus; seeing clear on the other side; or we would need to turn immediately to right to avoid thunderstorm in our 12 O'clock position. First officer advised ATC; 'we can turn left or right right now.' ATC responded 'roger.' at this point; our ability to turn left had passed. I picked up microphone and stated; 'we are turning right.' ATC objected so I declared an emergency. ATC asked how far right we needed to turn and I replied our current heading would do for about 5-10 mi then we could turn left around thunderstorm. Controller told us to turn right and I replied; 'negative.' he again asked us to turn right and I replied; 'negative; negative; we are emergency aircraft; once we get around thunderstorm we will cancel emergency.' he immediately switched frequencys to ZFW. ZFW asked the nature of emergency and I replied we did not get cooperation to avoid thunderstorm from prior center. Via ACARS was asked to contact center manager upon landing. I did and the controller manager said she could not see why we declared emergency. I told her to avoid possible injury/damage to aircraft. I also indicated I thought controller had lost situational awareness and to avoid flying into thunderstorm I exercised my emergency authority/authorized. No turbulence or chop was experienced during this incident. Manager controller said she was turning this over to their quality review department.

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Original NASA ASRS Text

Title: ACR AT FL330 DESCRIBED EVENT WHEN ATC'S REFUSAL TO PERMIT WX DEVIATION REQUIRED EMER DECLARATION.

Narrative: CRUISE FLT ABOUT MIDWAY OBSERVED LINE OF TSTMS DEVELOPING AND CLOSING IN APPROX ALONG A N/S LINE. OUR RTE WAS THROUGH THE LINE OF TSTM. APPROX 120 MI PRIOR ADVISED FLT ATTENDANTS THAT THEY SHOULD PLAN TO BE SEATED AND EQUIP STOWED IN 15-20 MINS. APPROX 40-50 MI PRIOR TO TSTMS; REQUESTED A DEV TO THE 'R.' ATC CLRED US TO A 180 DEG HDG. IT APPEARED THIS WOULD NOT BE QUITE ENOUGH. TO MAKE AN END RUN AROUND WHAT APPEARED TO BE THE OPEN AREA AND ALSO THE UPWIND (85 KTS) SIDE WE REQUESTED A HDG OF 190 DEGS. CTLR ADVISED UNABLE; HE WOULD BE DSNDING US AND THEN TURNING US. AS WE GOT CLOSER; CTLR WANTED US TO TURN L (E) THROUGH LINE OF TSTMS. WE REPLIED UNABLE BUT WE NEEDED TO TURN FURTHER R. AT A PARTICULAR POINT IN TIME; IT SEEMED WE COULD MAKE A L TURN AND GET BTWN SOME LARGE CUMULO NIMBUS; SEEING CLR ON THE OTHER SIDE; OR WE WOULD NEED TO TURN IMMEDIATELY TO R TO AVOID TSTM IN OUR 12 O'CLOCK POS. FO ADVISED ATC; 'WE CAN TURN L OR R RIGHT NOW.' ATC RESPONDED 'ROGER.' AT THIS POINT; OUR ABILITY TO TURN L HAD PASSED. I PICKED UP MIKE AND STATED; 'WE ARE TURNING R.' ATC OBJECTED SO I DECLARED AN EMER. ATC ASKED HOW FAR R WE NEEDED TO TURN AND I REPLIED OUR CURRENT HDG WOULD DO FOR ABOUT 5-10 MI THEN WE COULD TURN L AROUND TSTM. CTLR TOLD US TO TURN R AND I REPLIED; 'NEGATIVE.' HE AGAIN ASKED US TO TURN R AND I REPLIED; 'NEGATIVE; NEGATIVE; WE ARE EMER ACFT; ONCE WE GET AROUND TSTM WE WILL CANCEL EMER.' HE IMMEDIATELY SWITCHED FREQS TO ZFW. ZFW ASKED THE NATURE OF EMER AND I REPLIED WE DID NOT GET COOPERATION TO AVOID TSTM FROM PRIOR CTR. VIA ACARS WAS ASKED TO CONTACT CTR MGR UPON LNDG. I DID AND THE CTLR MGR SAID SHE COULD NOT SEE WHY WE DECLARED EMER. I TOLD HER TO AVOID POSSIBLE INJURY/DAMAGE TO ACFT. I ALSO INDICATED I THOUGHT CTLR HAD LOST SITUATIONAL AWARENESS AND TO AVOID FLYING INTO TSTM I EXERCISED MY EMER AUTH. NO TURB OR CHOP WAS EXPERIENCED DURING THIS INCIDENT. MGR CTLR SAID SHE WAS TURNING THIS OVER TO THEIR QUALITY REVIEW DEPT.

Data retrieved from NASA's ASRS site as of May 2009 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.