Narrative:

About 25 mi west of ord. We were climbing out of ord at about 7000 ft with WX radar on when we broke out of an overcast layer. In front of us was a buildup that did not show up on radar. Asked center for a 20 degree right turn and he said approved, followed by out of 9000 ft. We were around 8000 ft and said we need to turn now and he said now, and we said now and made the turn. No traffic seen on TCASII nor did the controller seem there was any problem. When received frequency change, I asked him if there had been a problem and he said no. If we did not turn we would have gone right into the buildup. We would have declared an emergency if the controller had said he was unable to let us turn.

Related reports:

Google
 

Original NASA ASRS Text

Title: ACR PIC RPT ON CLRNC INTERP WHEN DEVIATING AROUND TSTM ACTIVITY. USE OF NONSTANDARD PHRASEOLOGY LED RPTR TO INITIALLY BELIEVE HE HAD DEVIATED FROM ATC CLRNC.

Narrative: ABOUT 25 MI W OF ORD. WE WERE CLBING OUT OF ORD AT ABOUT 7000 FT WITH WX RADAR ON WHEN WE BROKE OUT OF AN OVCST LAYER. IN FRONT OF US WAS A BUILDUP THAT DID NOT SHOW UP ON RADAR. ASKED CTR FOR A 20 DEG R TURN AND HE SAID APPROVED, FOLLOWED BY OUT OF 9000 FT. WE WERE AROUND 8000 FT AND SAID WE NEED TO TURN NOW AND HE SAID NOW, AND WE SAID NOW AND MADE THE TURN. NO TFC SEEN ON TCASII NOR DID THE CTLR SEEM THERE WAS ANY PROB. WHEN RECEIVED FREQ CHANGE, I ASKED HIM IF THERE HAD BEEN A PROB AND HE SAID NO. IF WE DID NOT TURN WE WOULD HAVE GONE RIGHT INTO THE BUILDUP. WE WOULD HAVE DECLARED AN EMER IF THE CTLR HAD SAID HE WAS UNABLE TO LET US TURN.

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.