Large Transport
Flight Crew Air Transport Pilot (ATP)
Flight Crew Last 90 Days 55
Communication Breakdown
Deviation - Altitude Excursion From Assigned Altitude; Deviation - Track / Heading All Types; Deviation / Discrepancy - Procedural Clearance; Inflight Event / Encounter Weather / Turbulence
Air Traffic Control Provided Assistance
Human Factors; Procedure; Weather
Heavy weather and thunderstorms moving through the bay area. Winds were gusting on the surface and all Bay area airports were using non-standard runways. OAK closed while we were on arrival and aircraft were holding and diverting. The frequency was very congested. We were a couple of miles north of MNTNA intersection descending via the FRLON2 Arrival. A large cell was just past the MNTNA intersection and we asked Approach if we could maintain present heading for one to two miles for weather and then go direct MISSS. That request was approved. We finished the deviation and reported we were turning direct MISSS.The turn toward MISSS ended up being a fairly hard left turn. The Controller at one point asked if we were turning direct MISSS and we answered affirmative. He then said we weren't headed to MISSS and gave us a heading. The navigational display clearly showed we were headed to MISSS. After established on the heading we realized we hadn't been given an altitude after deviating off the arrival. We were at about 6500 feet with 5500 feet set in the altitude window. We asked what altitude we were cleared to and the Controller said 7000 feet. We said 'roger climbing back to 7000 feet;' and he said just maintain 6000 feet. He then gave us a frequency change and added that we were never headed toward MISSS. With all the frequency congestion and the high workload; we just shrugged; acknowledged the frequency and pressed. We never got an altitude clearance when cleared to deviate off the arrival; but we should have thought to ask.
[Report narrative contained no additional information.]
Air carrier flight crew; while deviating around weather; was questioned by ATC if they were proceeding to the cleared waypoint. The crew was convinced they were but ATC still questioned their track.