"The one answer I could not find was the minimum wx criteria when PRMs are used? Is it 1,000 ft, 1,500 ft or other ceiling or viz and what does the wx need to improve to in order for ATC to cease the PRM approaches, or is it also a matter of traffic/delays regardless of wx?"
Jenna Talia, it's up to the traffic manager to decide if we run PRM approaches but basically anything less than full IVA'S, PRM is the way to go. The acceptance rate for PRM is higher than any ILS/IVA rate. One possible reason they continued with PRM'S the other morning is maybe the Met people were forcasting some cloud to come in sometime soon. It's not so easy to go in and out of PRM's due to the longer downwinds required.
The suggestion of PRM'S running all the time is a good one, if we were serious about using this airport anywhere near it's capacity then we would run PRM anytime we could not do IVA'S.