Assistant Farbrace will stand in temporarily for head coach Trevor Bayliss for a one-off fixture against Australia at Edgbaston next week and the three-match series with India at the start of July.
Bayliss will return in time for three one-day internationals against India, starting at Trent Bridge on July 12.
Before then, Bayliss will watch England Lions in the remainder of their tri-series fixtures as well as the Royal London One-Day Cup final between Hampshire and Kent at Lord’s on June 30.
The Lions have limited-overs fixtures against both India A and West Indies A next week.
An England and Wales Cricket Board update read: “Paul Farbrace will be in charge of England’s T20 side for the Vitality IT20 matches against Australia and India.
“Head coach Trevor Bayliss will take a break from coaching duties and focus his attention during the two-week period watching the England Lions in the 50-over Tri-series competition against India A and West Indies A.
“He will also be in attendance at the Royal London One Day Cup final between Hampshire and Kent at Lord’s on Saturday, June 30 and will take the opportunity to watch some county cricket across the country.
“Bayliss will return to his role with England ahead of the ODIs against India starting at Trent Bridge on Thursday, July 12.”
Australian Bayliss, whose tenure started before the 2015 Ashes, has previously had minimal opportunity to see any prospective England players in domestic action.
England spinner Jack Leach’s comeback game following a finger injury ended in more pain as he suffered a concussion during Somerset’s innings defeat to Surrey in the County Championship.
Somerset became the second team in county cricket to enforce the new ruling regarding ‘concussion substitute’ after Leach was hit on the head by South African pacer Morne Morkel during the first innings. Leach continued to bat as Ryan Patel finished with figures of 6-5 and forced Somerset to follow on.
Somerset fared no better in their second outing after trailing Surrey’s 459 by 279 runs. They were bowled out for 210 in Guildford with Leach unable to bat and Max Waller used as the concussion substitute.
It was Leach’s comeback match after a finger injury ruled him out of England’s Test series against Pakistan and Somerset’s county game against the Notts.
Earlier, Lancashire employed Danny Lamb as a substitute for Joe Mennie in their game against Worcestershire after Mennie was hit on the head by a straight shot from Martin Guptill.
Jason Roy smashed a century as England chased down 311 inside 45 overs after scoring a world-record 481-6 in the third match of the series.
“If it does become the ‘normal’, that would be awesome because it creates an unbelievable tone at the top of the order,” Morgan said of the England top three.
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