Date: 201703
Local time of day: 1201-1800
Location: PIT.Airport, PA
Aircraft: B737-800
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach
Airspace: Class B PIT
ATC / advisory: Tower PIT
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Human factors: Time Pressure
Second reporter function: Pilot Not Flying; First Officer
Anomaly: Inflight Event / Encounter Fuel Issue; Inflight Event / Encounter Unstabilized Approach; Inflight Event / Encounter Weather / Turbulence
Detector: Person Flight Crew
When detected: In-flight
Result: Flight Crew Diverted; Flight Crew Took Evasive Action
Contributing factors: Procedure; Weather
Primary problem: Weather

Narrative: Flight to ZZZ. We executed two missed approaches into ZZZ because of winds in excess of 50 knots at ZZZ. After the second missed approach we proceeded to the planned alternate; which was PIT. When we left ZZZ for PIT the winds on ATIS at were 240 at 20 knots gusting 34 knots. When we were approaching we received ATIS and winds were 270 at 30 knots G53 knots and gains and losses of 20 knots on final were reported. We briefed 28L visual approach and talked about all the ramifications of very gusty winds on final. We had fuel for the first approach and one very quick go around and return to PIT if absolutely necessary. We discussed using my Captain's authority to land above the 50 knots and the possibility of an unstable approach using [Company] and FAA policies and go-around procedures. We did not have the fuel to go anywhere else.We intercepted final for 28L and Tower reported the winds gusting to 44 knots and down the runway (I don't remember the exact winds; but I do know they were gusting to somewhere in the mid 40 knots). We were experiencing light and occasional moderate turbulence at this point. Tower cleared us to land on 28L. We intercepted the localizer and glide slope on the ILS 28L. We were 5 to 10 knots fast at 1;000 feet and I was correcting. At approximately 600 feet we experienced a 20 knot gain in airspeed. I pulled the throttles back some; but not all the way to idle; to avoid flap 30 over speed. I was hesitant to pull them all the way back to idle in case the airspeed suddenly dropped off so I pulled the nose up slightly to bleed airspeed which put us above glide slope. We did not meet stable approach criteria at 500 feet; but I was confident in my ability to land in the situation and a third go-around was going to put us very fuel critical. It was a smooth landing at approximately 1;500 down the runway. I felt like we had to land if it could be done safely. 28L is 11;500 feet long and at this point I was only going to go-around if I became convinced that I couldn't land safely. Our rate of descent was never excessive (1;100 FPM max) and we didn't land out of the touchdown zone. We slowed and exited at high speed taxiway F5 from 28L.In hindsight; I would have preferred a better alternate; but I had no way of knowing that PIT's winds would change so drastically from forecast.


Second narrative: One lesson learned is that ZZZ advised us that they were reporting winds to us on final that were a 2 minute average. We asked for spot winds on the second approach at ZZZ; but at 500 feet the winds reported to us were still above 50 knots. They sounded like the exact same winds that were reported on the first approach; so we are unsure if we actually received spot winds. While 2 minute average winds are helpful to analyze current conditions and max gusts; when winds are near limits; it would be preferred to receive exact winds when requested during the approach.With respect to the approach at PIT; I think Captain did a great job briefing his intentions and making a difficult decision to continue the approach knowing he would be second guessed. No one wants to be in a position where you have no option; but to land due to insufficient fuel and Captain was able to avoid that scenario. He did an excellent job flying a safe approach and landing in very challenging conditions and received many thanks from the passengers as they deplaned in PIT.The winds at PIT were not forecast to exceed or even approach 50 knots. After checking the PIT ATIS while on downwind at ZZZ and seeing suitable conditions; we did not expect to arrive and find winds beyond limits at PIT or we would have looked for other options. My thoughts about avoiding this in the future are focused on the wind callouts by ZZZ Tower. I am not sure if it is FAA procedure to call out winds that are a 2 minute average that may only be for the gust factor; but I would like to know if we would have been able to land legally if we received spot winds less than 50 knots. Also; winds indicated on the PFD never exceeded 50 knots and I wonder if we could use those winds; along with other information for situational awareness; to make a decision on a safe and legal landing.


Synopsis: B737-800 flight crew reported an unstable approach as a result of gusty winds at the end of a divert from another airport also experiencing gusty winds.