Date: 201505
Local time of day: 1201-1800
Location: PAO.Airport, CA
Flight conditions: VMC
Weather elements / visibility: 30
Light: Daylight
Aircraft: Small Aircraft; Low Wing; 1 Eng; Retractable Gear
Operator: Personal
Operating under: Part 91
Flight plan: None
Mission: Personal
Flight phase: Descent
Airspace: Class D PAO; Class E NCT
ATC / advisory: TRACON NCT; Tower PAO
Reporter organization: Personal
Reporter function: Single Pilot
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Flight Instructor
Human factors: Communication Breakdown
Anomaly: ATC Issue All Types; Airspace Violation All Types
Detector: Person Flight Crew
When detected: In-flight
Result: Air Traffic Control Issued Advisory / Alert; Air Traffic Control Issued New Clearance; Flight Crew Became Reoriented
Contributing factors: Airspace Structure; Procedure
Primary problem: Ambiguous

Narrative: I was on a return flight from the valley. The route was the same ZZZ-VPKGO-Traintressel for a right 45 into PAO- that I had flown hundred of times before and always flight-following with NorCal until the handover to PAO Tower around Leslie Salt. I started a 500 foot descent from 6;500 feet 25 miles out of KGO as always. After a handoff from NorCal just before Leslie Salt; I contacted PAO Tower as instructed by NorCal; at about 2;500 feet between Leslie Salt and KGO (outside Class D) with the note to Tower 'direct KGO; then Traintressel for a right 45 due to being (still) high and fast (160 kts). Tower came back with 'right base approved'. I responded 'I'll take direct KGO; then Traintressel'. Tower then pointed out traffic at two locations ahead of me; one at roughly my altitude and one lower and asked for acknowledgment; which I gave shortly thereafter. Tower also requested (I think it was at that transmission or one after that) to remain at 2;500 feet but gave no reason! I acknowledged the traffic contact AGAIN after being asked for it by Tower and at about 2;300 feet of altitude; Tower -FOR THE FIRST TIME- in a very fast voice mentioned a TFR near Leslie Salt at 19.4m nm from OAK VOR from 2;000 feet down to the surface. This was the first time ANYONE mentioned a TFR being in effect for an area that I might have already flown through... NOT PAO ATIS Romeo; which I called prior to departure. No mention by any of the THREE NorCal controllers! No mention by the updated PAO ATIS; which I received around XA:35 near Patterson/I-5 at 6;500 feet. AND no mention by PAO Tower after the initial call-up and subsequent THREE submissions!!! And when PAO Tower finally mentioned that there was a TFR in my immediate area I was directed to remain at 2;500 feet (at that time I was about 2 miles outside of Class Bravo) RIGHT INTO CLASS BRAVO!! My next transmission was' That'll get me right into Class Bravo; Man!' No response from Tower until I was close to the Traintressel and cleared to land as #2 on Runway 31.I have no idea whether I was below 2;000 feet in that 2-mile TFR or not. The situation was so unsettling that all I remember being 2;300 feet about 2 miles from KGO and descending.I understand that I have a responsibility per Part 91 CFR to 'obtain all available information' on the destination airport which I did part of it by calling PAO ATIS before my preflight. And TFR at that time had not been in effect. So if a pilot experiences a 'pop-up' TFR during flight; how [are they] supposed to find out if the controllers don't relay that information?Lastly; I checked on my cell after the landing in PAO and found out that the 'Newark Police Department' was the official contact for this 'Hazards-based' TFR. Since when can a local small-town police department declare sudden TFR's? There was a [police] situation on the ground in Newark; okay; but a TFR for that?




Synopsis: A General Aviation pilot is informed by PAO Tower during approach that a law enforcement TFR is in effect along his approach path; 2;000 feet and below. The reporter had been unaware until this point and thought that the information should be part of the PAO ATIS.