Date: 201411
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Weather elements / visibility: Rain; Turbulence
Light: Daylight
Aircraft: Large Transport; Low Wing; 2 Turbojet Eng
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Initial Approach
Airspace: Class B ZZZ
ATC / advisory: TRACON ZZZ
Reporter organization: Government
Reporter function: Approach
Reporter qualification: Air Traffic Control Fully Certified
Human factors: Workload; Troubleshooting; Situational Awareness; Confusion; Communication Breakdown; Distraction
Second reporter function: Approach
Anomaly: ATC Issue All Types; Conflict Airborne Conflict; Deviation / Discrepancy - Procedural Published Material / Policy; Inflight Event / Encounter Weather / Turbulence
Detector: Person Air Traffic Control
When detected: In-flight
Result: Air Traffic Control Separated Traffic
Contributing factors: Procedure; Human Factors; Weather; Airspace Structure; Environment - Non Weather Related
Primary problem: Procedure

Narrative: I was working DR1 during a flow change at ZZZ airport from south flow to north flow as weather passed over the airport.  I was informed by a TMU specialist that a specific aircraft was the last to depart.  I asked if we were shutting down the airport (no one had told me we were turning the airport around the other direction yet).  The specialist didn't answer me.   I found out a few minutes later from a supervisor that the airport was in fact changing direction.  After the aircraft I was told was the last to depart had come airborne; I was surprised to see yet another departure; and then a 3rd.  I asked the specific TMU specialist what was going on; and he informed me that the 2nd aircraft was now the last.  Around that time; as one of the departures came airborne (I don't remember which; but I think it was the 3rd one); a data-block was forced to my display from the arrival controller.  My aircraft were still departing off of Runway 17; and this data-block was an arrival; opposite direction; at 3;000 feet to Runway 36. No one from TMU informed me that there was an emergency aircraft inbound opposite direction; nor did I have any reason to believe any more departures were coming off opposite direction from Runway 17.  When my departure aircraft lost separation with the opposite direction arrival; I first asked the TMU specialist again what was going on. Since I didn't get any answer whatsoever; I then called the tower and asked them how many more aircraft were departing Runway 17; into the arrivals now coming to Runway 36. The local controller in the East Tower informed me he had 2 or 3 more to launch before they turned around to north flow. I said they need to hurry up because we had all this other stuff coming inbound now to the airport from the south; and I needed to get those departures out of the way. I had no idea what was going on; nobody at TMU informed me of the situation.  What little information I was told turned out to be inaccurate; as I continued to receive departures after the aircraft I was told was last; had departed.  Had I been informed of the opposite direction arrival to 36; I would have immediately informed the east tower to hold all departures.  I was utterly surprised to see the departures keep departing and the arrival suddenly displayed to me south of the airport inbound towards my departures.I recommend that before our TMU starts making decisions; they figure out what it is they need and stick with it.  A constantly changing plan is fine; however; people need to be informed. TMU was absolutely not informing me of what was going on throughout the entire day; regardless of where I sat (I will be filing a separate report on that shortly). The departure incident cited above is a direct result of miscommunication and misinformation between TMU and the departure/arrival controllers and FLM's.  Again; had I been informed; I could have easily stopped the departures and avoided this incident altogether.


Second narrative: I was working Arrival 3 and ZZZ airport was in a south flow running widely spaced approaches to the south runways XXR and XYL.  I was the side and was descending my aircraft to 3;000 feet; but they began complaining of severe turbulence at 3;000 feet. I advised the training team on Arrival 1 that I was going to be the high side and they needed to go low due to the turbulence.  This adjustment was made with no issues.  We then transitioned to monitored approaches with Arrival 3 (me) working Runway XXC while Arrival 1 worked runway XXR.  Soon thereafter a large cell of heavy/extreme precipitation began to build around the fix for Runway XXC and XXR.  There was no room to legally run aircraft to these runways with the weather so we transitioned quickly to XAR and XXC.  The first aircraft on the XAR final reported severe turbulence; asked to be vectored off the approach; and advised that no aircraft should go through this.  We then transitioned to a north flow operation where the aircraft would have to land with a slight tail wind knowing that the storm front that was approaching would force us to go north flow anyway.  At this point; we had aircraft everywhere in our airspace holding at multiple altitudes.  An air carrier on my frequency advised he was only 2 to 3 minutes from having to declare a fuel emergency.  I advised the supervisor of the situation and even mentioned that tower needed to take their remaining 3-5 departures and taxi them to the south end of the airport to depart north flow.  I was instructed to start vectoring the carrier towards Runway XZL final and was told when the departures were clear that I could clear the carrier for the approach.  Although there were no departures departing XYL; ZZZ tower east continued to launch their remaining 2 airplanes off of XXR. Another carrier was the last to depart XXR and a loss of separation occurred with the low fuel aircraft on the final for XZL.I recommend somebody make a decision next time and execute it.  There is no reason the tower could not have taxied the remaining aircraft to the south end of the airport for a north departure.  Communication was a major factor in this event.


Synopsis: Arrival Controllers describe situation of a configuration change that didn't go smoothly resulting in a loss of separation with an opposite direction arrival.