Date: 201909
Local time of day: 0601-1200
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: 10
Light: Daylight
Aircraft: Small Transport
Operator: FBO
Operating under: Part 91
Flight plan: None
Mission: Skydiving
Flight phase: Cruise
Airspace: Class E ZZZ
ATC / advisory: TRACON ZZZ
Reporter organization: FBO
Reporter function: Single Pilot
Reporter qualification: Flight Crew Instrument; Flight Crew Multiengine; Flight Crew Commercial
Human factors: Communication Breakdown; Situational Awareness; Time Pressure
Anomaly: Deviation / Discrepancy - Procedural FAR; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew; Person Observer
When detected: In-flight
Result: Flight Crew Returned To Departure Airport
Contributing factors: Company Policy; Weather; Procedure
Primary problem: Procedure

Narrative: I took off from ZZZ to conduct skydive operations. VFR conditions prevailed and VFR flight was maintained through the duration of the flight. I climbed to the south of the field. The climb was to level off to a jump altitude of 17;500' MSL over the airfield. A scattered layer of clouds approximately 2000' AGL started to form south of the airfield and appeared to be moving northwest at a slow pace during my climb.  The plan was to conduct a jump run parallel to the extended centerline of Runway XX/XY with an offset of 0.2 NM south of the airfield. During the climb I communicated with the Ground Spotter directly on how our plan was looking. Furthermore; appropriate calls were made both to Approach and the local CTAF frequencies; and supplemental oxygen was utilized.Due to the clouds moving north; we agreed that we would move jump run 0.4 NM north from the original spot which placed the aircraft 0.2 NM north the centerline of Runway XX/XY. Upon turning base leg for jump run at an altitude between 16;000' MSL and 17;000' MSL; I had the drop zone in sight; and I double checked with my Ground Spotter to confirm that the modified jump run plan held integrity. My primary visual reference on jump run is a sight picture of the foothills/mountains. This sight picture is attained by establishing the desired offset through GPS way points programmed into a Garmin G430. These way points define the extended centerline of Runway XX/XY.Once stabilized and configured on jump run; I confirmed one last time with my Ground Spotter that our spot was appropriate for skydiving operations. After verbal confirmation with my Ground Spotter; I set the jump light to amber which signifies to the jumpers that they can open the door of the aircraft and spot their landing. Shortly thereafter; I set the jump light to green which signifies to the jumpers that they can jump; provided they have spotted their landing area. Once again; appropriate radio calls were made both to Approach and CTAF. The information available to me provided no reason to withhold jumpers from conducting their jump.  All jumpers left the aircraft. As soon as jumpers were away; I got an additional call from a different ground crew member to 'red light' or stop jumpers from exiting the aircraft. It was unfortunately too late as all jumpers had exited. I descended maintaining VFR; and landed at ZZZ. All jumpers made it back to the designated drop zone without issue. I feared jumpers may have gotten too close to the scattered clouds that were developing.I believe there are a few factors contributing to this occurrence. First and foremost; the changing weather and developing clouds moving north are the centerpiece of this occurrence. Secondly; the jumpers' decision to get out of the aircraft is their responsibility just as much as it is mine. As stated previously; my perception of the situation at hand gave no reason to withhold sky dive operations. I provided the jumpers with the criteria they needed to conduct a safe jump. Jumpers have the best view of the drop zone out of anybody; and must decide if they can maintain the criteria for a safe jump (cloud clearances; safe landing at the designated drop zone; etc.). Although corrective actions couldn't be applied to the stated occurrence; I decided to put jump operations on a 'weather hold' until ALL clouds were well clear of the drop zone.




Synopsis: Sky dive pilot reported possibly canceling the jump due to clouds in the area; but decided against it.