Narrative:

ZZZ weather was below VFR minima. Aircraft X was cleared for ILS approach to ZZZ via (IAF). Between [IAF] and the localizer; the pilot of aircraft X reported the airport in sight and requested a visual approach. I instructed the aircraft to continue via the ILS approach for departing traffic. When the departure was airborne; I asked aircraft X if he still had the airport in sight and he responded that he did. I cleared the aircraft for a visual approach. I coordinated the visual approach with ZZZ tower and then terminated radar service with the aircraft and transferred communication to ZZZ tower. As the aircraft was descending through approximately 1;100 ft MSL; I realized I did not have weather minima for a visual approach and called ZZZ tower and told them. The controller at ZZZ offered to send the aircraft back to me but at that point I determined it was safer to allow the aircraft to continue to a straight in landing as he was already at the ZZZ VOR 900 ft below the mia but within the confines of the ILS localizer at an altitude appropriate for the approach. The aircraft landed without incident. Recommendation; shortly before clearing the aircraft for the ILS approach; ZZZ tower had called to return the class D/east surface area. The aircraft reported having the current ZZZ ATIS information. With the return of the surface area; and the aircraft reporting having the current weather; I assumed the weather was VFR. I should have checked to verify the reported weather prior to clearing the aircraft for a visual approach from the ILS.

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Original NASA ASRS Text

Title: Enroute Controller described an incorrect issuance of a visual approach clearance when an IFR aircraft on final requested same even though the weather was still IFR.

Narrative: ZZZ weather was below VFR minima. Aircraft X was cleared for ILS approach to ZZZ via (IAF). Between [IAF] and the localizer; the pilot of Aircraft X reported the airport in sight and requested a visual approach. I instructed the aircraft to continue via the ILS approach for departing traffic. When the departure was airborne; I asked Aircraft X if he still had the airport in sight and he responded that he did. I cleared the aircraft for a visual approach. I coordinated the visual approach with ZZZ Tower and then terminated RADAR service with the aircraft and transferred communication to ZZZ Tower. As the aircraft was descending through approximately 1;100 FT MSL; I realized I did not have weather minima for a visual approach and called ZZZ Tower and told them. The Controller at ZZZ offered to send the aircraft back to me but at that point I determined it was safer to allow the aircraft to continue to a straight in landing as he was already at the ZZZ VOR 900 FT below the MIA but within the confines of the ILS localizer at an altitude appropriate for the approach. The aircraft landed without incident. Recommendation; shortly before clearing the aircraft for the ILS approach; ZZZ Tower had called to return the Class D/E surface area. The aircraft reported having the current ZZZ ATIS information. With the return of the surface area; and the aircraft reporting having the current weather; I assumed the weather was VFR. I should have checked to verify the reported weather prior to clearing the aircraft for a visual approach from the ILS.

Data retrieved from NASA's ASRS site as of July 2013 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.