These are uncharted waters for Birmingham who were one of the clubs expected to be fighting a relegation battle.
Jerome's goals gave Birmingham their fifth successive win and their best ever run of success in the Premiership.
But Jerome epitomises the spirit in the Birmingham side at the present time. His enthusiastic running and his partnership with Christian Benitez has been a main reason for City's recent improved form.
Struggling Blackburn had no answer to Jerome's positive play and paid the penalty as they slumped to their 12th away defeat in 13 games despite skipper Ryan Nelsen pulling back a 69th-minute goal.
Jerome, who had previously only scored one goal, was on the mark in the 12th minute and added his second three minutes after the break.
Birmingham's latest success demonstrated their confidence which has been generated over the last month and they were in a confident mood from the start as they attempted to build on their recent impressive form.
Blackburn were under considerable pressure from the hugely confident home team who were determined to build upon their recent unbeaten run.
The pressure paid off in the 12th minute following a Seb Larsson corner which was headed on by Benitez. Liam Ridgewell then pushed the ball back into the middle where Jerome was on hand to finish off from close range for only his second goal of the season.
Benitez had the ball in the net but his effort was ruled offside to the relief of a Blackburn side which had their backs to the wall at this stage.
Blackburn were eager to get back on level terms with Nikola Kalinic producing some skilful play but Birmingham's resolute defence, which has the best home record in the Premiership, were in no mood to concede.
Kalinic had the best opportunity to equalise but the former Hajduk Split player completely missed his kick in the six-yard area.
With Scotland international Barry Ferguson controlling the midfield, Birmingham were generally in command but, as against West Ham in the previous game, they were unable to consolidate their lead.
Nothing appeared to be going Blackburn's way and they had Steven N'Zonzi booked before half-time.
The game, however, was settled three minutes after the restart when skipper Stephen Carr raced forward and pulled back a low cross from the right which Jerome guided in past Paul Robinson.
Blackburn battled gamely and, following a Morten Gamst Pederson free-kick in the 69th minute, Nelsen bundled the ball home after Joe Hart had saved a Jason Roberts effort.
Benitez hit the bar in the closing stages and Robinson saved from Larsson but Birmingham were full value for their record-breaking victory.