The 37-year-old will step up from his role as assistant coach while regular boss Jim Troughton works with The Hundred's Birmingham Phoenix
Warwickshire assistant coach Ian Westwood will take the reins at the county during this summer's Royal London Cup campaign.
The move comes after regular first-team boss Jim Troughton was recruited by The Hundred's Edgbaston-based Birmingham Phoenix franchise to work alongside men's team head coach Andrew McDonald for the duration of the competition.
Westwood, who made 56 apperances for the county in List A cricket between 2005 and 2013, follows Worcestershire counterpart Alan Richardson in being confirmed as an interim leader for the 50-over competition.
Speaking about the 37-year-old's promotion, Warwickshire's sporting director Paul Farbrace praised the contributions Westwood had made to the county since joining the back-room staff upon his retirement in 2017.
"I've been very impressed with Ian and he has the makings of an excellent coach," Farbrace remarked.
"He played an important role in helping Rob Yates, Dan Mousley, George Garrett and Ethan Brookes step up from the academy to the professional ranks last year and he has made good progress with the 2nd XI, where he has further supported the development of several other promising young players.
"We're committed to giving opportunities to our coaches, as well as the players, to be the best that they can."
"With Jim benefitting from this excellent opportunity to work on a premier short-form tournament, it's right that Ian can grow as a coach by leading on first team matters with the support of Graeme [Welch, bowling coach] and Tony [Frost, batting coach]."
The Bears, whose Royal London Cup schedule includes a brace of fixtures at the Edgbaston Community Sports Ground in its first appearnce on the first-team calendar since 1961, are set to be without at least four members of their squad after they won gigs at the new competition at last October's draft event.
England star Chris Woakes will join county colleagues Adam Hose and Henry Brookes alongside coach Troughton for Birmingham Phoenix, while opener Ed Pollock will feature at Old Trafford for Simon Katich's Manchester Originals outfit.
Image: Tony March / Cricpix.com
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