Narrative:

I was working west radar during a runway change from northeast to southwest landing direction. I had a departure going southeast. I handed aircraft off to east radar but held onto aircraft to put him over the airport to get above departure and arrival traffic. Simultaneously east radar had a departure going northeast but needed a turn to the north. I observed a jet off the arrival and told east radar that they could go into my airspace with aircraft X. My intention with this was roughly a 350 heading to ride the boundary to allow the climb with the arrival medevac. I turned a VFR aircraft; aircraft Y; at 4500 feet to heading 180 to go directly over the airport. The east controller had turned aircraft X further west than I anticipated. I saw the conflict and advised east radar. Aircraft X was at 3700 feet when east issued aircraft X to stop at 4000 feet. I immediately turned my aircraft further southwest to avoid an RA and called traffic. Aircraft Y reported the air carrier in sight and was instructed to maintain visual with aircraft X who was at 4200 descending back down to 4000. Aircraft Y then descended rapidly into aircraft X anticipating that aircraft X was climbing. I had advised aircraft Y that aircraft X was at 4000 feet. Aircraft X responded to an RA causing him to descend.my aircraft was in east radar's airspace. However; the runway change we were performing put him in my airspace. This caused the aircraft to be on 2 different frequencies. Additionally; I should have been more clear about my intentions with aircraft Y and ascertained east radar's intentions more clearly.I should have had better situational awareness for myself. With the complexity of the runway change I did let aircraft Y extend further east than normal. I should have been clearer about my intentions.

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Original NASA ASRS Text

Title: RSW TRACON Controller reported during a runway/airspace change he approved an adjacent sector's aircraft to enter their airspace resulting in a conflict with a VFR aircraft they were working.

Narrative: I was working West Radar during a runway change from NE to SW landing direction. I had a departure going southeast. I handed aircraft off to East Radar but held onto aircraft to put him over the airport to get above departure and arrival traffic. Simultaneously East Radar had a departure going northeast but needed a turn to the north. I observed a jet off the arrival and told East Radar that they could go into my airspace with Aircraft X. My intention with this was roughly a 350 heading to ride the boundary to allow the climb with the arrival Medevac. I turned a VFR aircraft; Aircraft Y; at 4500 feet to heading 180 to go directly over the airport. The East controller had turned Aircraft X further west than I anticipated. I saw the conflict and advised East Radar. Aircraft X was at 3700 feet when East issued Aircraft X to stop at 4000 feet. I immediately turned my aircraft further southwest to avoid an RA and called traffic. Aircraft Y reported the air carrier in sight and was instructed to maintain visual with Aircraft X who was at 4200 descending back down to 4000. Aircraft Y then descended rapidly into Aircraft X anticipating that Aircraft X was climbing. I had advised Aircraft Y that Aircraft X was at 4000 feet. Aircraft X responded to an RA causing him to descend.My aircraft was in East Radar's airspace. However; the runway change we were performing put him in my airspace. This caused the aircraft to be on 2 different frequencies. Additionally; I should have been more clear about my intentions with Aircraft Y and ascertained East Radar's intentions more clearly.I should have had better situational awareness for myself. With the complexity of the runway change I did let Aircraft Y extend further East than normal. I should have been clearer about my intentions.

Data retrieved from NASA's ASRS site and automatically converted to unabbreviated mixed upper/lowercase text. This report is for informational purposes with no guarantee of accuracy. See NASA's ASRS site for official report.