According to the latest weather forecast, highs will be in the lower to mid 70's, and lows in the low 50's or even high 40's this weekend. Wednesday is usually a pretty good day to predict weekend weather for the coming weekend. This is an ideal weather forecast for elk viewing.
If you have been timing your visit, this weekend is a great choice. The elk rut is at the beginning of the peak. For photographers clear skies will make photography more difficult, but there are many good pictures to be had at the ends of the day. The field at the south end of Boxley Valley is on the west side of 21 so the early light would be ideal. Most other fields in the valley are better suited to evening shooting, they are on the east side of the highway.
If you spend the day, this is also ideal hiking weather. During the mid day the elk will probably not be visible. Consider taking a side trip to Lost Valley. It is located in the upper third of Boxley Valley near the elk observation pullout. The trail is ideal for families. It is relatively flat, short, and very scenic. It is consistently rated at the top of hiking trails in the Buffalo National River system.
Visitors should also plan on visiting the award winning Ponca Elk Education Center in Ponca. This is a national class facility. It has many educational exhibits and free posters, educational materials, and paper antlers for the kids.