Right now is a perfect time to treat for mites. Just because you don't see mites doesn't mean that they are not there. If you start seeing mites on bees the mite population is very high in the hive. Be proactive, the hive you save may be your own.
The weather is perfect right now for Formic Pro or Mite Away Quick Strips. Both of these treatments are considered organic and can be applied with supers on the hive.
Treating now will lower the mite population before the bees start making winter bees, which usually starts around mid to late August.
Winter bees are the bees that live through the winter. Winter bees have a different physiology than summer bees. Winter bees have the ability to store more lipids (fat) in their bodies.
Having winter bees as mite free as possible is the key to overwintering success.
Waiting to treat your bees into September can cause your winter bees to be weakened and get viruses by a higher mite population. The odds of survival are much lower.
Dave Dahl from KSTP is forecasting hot weather coming back in about a week. If it is too hot, you may not be able to use Formic Pro or MAQS, other mite treatments will have to be used.