Flights: There are direct flights to Munich from different cities in the U.S., e.g., Boston, and other countries via different airlines with a train connection to Munich. There also trains from Munich airport to Augsburg (1.30 mins for $17 to $36) or from Munich train station (half hour for $2-$4). There are also busses and share rides from the airport.
Train site from Munich: https://www.rome2rio.com/map/Munich/Augsburg
Train Site from Munich Airport: htpps://www.rome2rio.com/map/Munich-Airport-MUC/Ausgrburg
Climate: The weather at the end of June varies from 71 F / 56 F
Visa Requirements: At this point in time, the U.S. passport holders do not need a visa for a short stay (3 months) in Germany. For the EU countries no visa, and other countries, please visit the site: https://www.schengenvisainfo.com/germany/