The beginning of the advertised pattern change on the extended products is evident at the very end of the latest ens runs. The NPJ is forecast to be (too) extended for the last week of the month, but around NYE there is some retraction that relocates the exit region, so the GoA trough retrogrades while a downstream h5 ridge starts to redevelop. The jet configuration has been shifting, so its hard to say how stable this will be. In general a retracted jet is favored in a Nina, but with the weak nature of it(and tropical forcing) who knows. When it retracts too far westward the characteristic Nina NPAC ridge develops.