In the absence of Gregor Townsend, Blair will step up as interim head coach for the three-game programme.
The former Scotland scrum-half and captain will be joined on the tour by Jim Mallinder, Scottish Rugby’s director of high performance.
Townsend is on British & Irish Lions duty in South Africa, along with the Scotland defence coach Steve Tandy.
The Scotsman can reveal that the first game of the summer schedule will see Scotland A play their English counterparts in late June on a date and at a venue yet to be confirmed.
The full national team will then head to Europe to face Romania on July 10 and Georgia on July 17 in Test matches. Kick-off times, venues and broadcast arrangements are yet to be finalised but the intention is for the games to be played in Romania and Georgia, Covid permitting.
Blair will be supported by national forwards coach John Dalziel and scrum coach, Pieter de Villiers. Peter Murchie, the recently appointed Glasgow Warriors assistant coach, will also join the coaching team on tour.
Blair, who has been part of the Scotland set-up since 2017 as an assistant coach specialising in attack, said: “I’d like to thank Gregor and Jim for this opportunity to lead the Scotland summer tour and I’m looking forward to continuing to build the positive culture and results we have achieved in recent months.
“This tour gives us the chance to work with a wider group of players and see how they can step up into the international game, whilst also continuing to look to improve with our established Scotland players.
“The three matches will present very different challenges and as a squad and coaching group we will be looking to continue to create depth and competition for places within strong team performances.”
With several Scotland players expected to be selected for the Lions’ trip to South Africa and others rested or recuperating after a long international season, there is likely to be the opportunity for several fringe contenders to stake a claim.
Mallinder said: “The opportunity to put out a Scotland A side enables the coaches to see and work with a wider group of players with an eye on the future, before we face two Test matches, away from home, against quality opposition in Georgia and Romania.
“It also gives me personally a chance to spend time with coaches and players which will help develop those important relationships and connections that come with spending an extended period of time together.”
Scotland last played Romania at the 2011 Rugby World Cup in New Zealand, winning 34-24 in a pool match in Invercargill during Andy Robinson’s tenure as head coach.
They played Georgia last autumn in Edinburgh and won 48-7 in a match in which Duhan van der Merwe made his Scotland debut, scoring a try in the process.