B737-700
Flight Crew Multiengine; Flight Crew Air Transport Pilot (ATP); Flight Crew Instrument
Flight Crew Last 90 Days 511
Communication Breakdown; Distraction; Situational Awareness
Deviation / Discrepancy - Procedural Published Material / Policy; Ground Event / Encounter Other / Unknown
General None Reported / Taken
Human Factors; Airport
We landed just prior to a storm hitting the field and subsequently closing the airport. On taxi in; Operations advised us the ramp was closed due to lightning; however; they could use the Mobile Aircraft Parking System (MAPS) to park us at XXX. They would not be able to chock us and bring up the jet bridge due to the closed ramp. We decided to wait on Taxiway A until the storm passed; and the ramp opened. After approximately 30 minutes; Operations radioed us to let us know the Supervisor was in the MAPS vehicle at our gate and that he would direct us in and be able to chock the aircraft to allow the jet bridge to approach the plane; even though the ramp was still closed. We proceeded to the gate.It was nighttime and the visibility was poor due to rain and wet surfaces making it very difficult to see the taxi lines or the J-line. We attempted to line up with the MAPS vehicle and realized we were well to the right of the J-line. We came to a stop because we were not lined up properly and noticed the MAPS vehicle was lined up on the right side of the J-line from our view. We had thought the MAPS vehicle was directly over top of the J-line and they were not. I had to make a hard left inside the Safety Zone to line up with the J-line and park the aircraft.  After parking the aircraft; I realized how dumb an idea the MAPS vehicle really is. We are required to have a Marshaller; and two wing walkers when the weather is good. When the visibility is poor; it's dark; and the ramp is closed; it's acceptable to use a truck with lights to park the aircraft? The MAPS vehicle was in the wrong position for parking and we lined up with it. We could have easily hit something in the very congested XXX gate area because of bad operational ideas (i.e. MAPS vehicle). I allowed Operations to talk me into taxiing into the gate with the MAPS vehicle and I completely regret making that decision.
B737 Captain reported an unsafe environment when using the Mobile Automatic Parking System during ramp closure due to lack of personnel and tight clearances while taxiing to the gate with thunderstorms.