Possibly R. Capistrano? That is the yellow I see most often in nureries that are in the same zone as you. A picture would make it easier.

Zone 5 and yellow rhododendrons don't mix well. All yellow rhododendrons are prone to root rot. They are also more tender. R. Capistrano is one of the best selling plants. Most people buy several since when the first one dies they replace it with another. It is quite profitable for nurseries, but not for gardeners.

Enjoy it while it lasts. Don't expect too much. Guard against root rot. This means use a raised bed with excellent drainage, avoid too much sun, and use a good layer of mulch to keep the roots cool. Cool roots and good drainage will keep it alive longer.