Date: 201705
Local time of day: 1201-1800
Location: ZZZ.Airport, US
Flight conditions: VMC
Weather elements / visibility: Cloudy; Rain; Icing; 9
Aircraft: A320
Operator: Air Carrier
Operating under: Part 121
Flight plan: IFR
Mission: Passenger
Flight phase: Final Approach; Landing
Airspace: Class B ZZZ
ATC / advisory: Tower ZZZ
Aircraft component: GPWS
Component problem: Malfunctioning
Reporter organization: Air Carrier
Reporter function: Captain; Pilot Not Flying
Reporter qualification: Flight Crew Air Transport Pilot (ATP)
Second reporter function: Pilot Flying
Anomaly: Aircraft Equipment Problem Less Severe
Detector: Automation Aircraft Terrain Warning; Person Flight Crew
When detected: In-flight
Result: Flight Crew Overcame Equipment Problem; General Maintenance Action
Contributing factors: Aircraft
Primary problem: Aircraft

Narrative: I believe we did everything correctly and this is a safety issue related to OEB XXX-X. At no point did I feel the continuation or safe conduct of the flight was in jeopardy with all the visual references and instrumentation available. We were set up for an approach to RWY 32 at PIT. Winds on second to last ATIS we received were reported to be gusting around 310-320 at 21 G 26 kts. They had calmed down to about 320 at 13 kts at time of landing. During the descent between 12;000 to 8;500 feet we were in and out of the clouds with moderate rain and the temperature varied between +13C and 8 degrees. There were Airmet's for icing for the state. ATC was vectoring us away from the more intense rain areas. We went through one more layer of clouds; but picked up the airport well outside the FAF. We had 9 miles visibility. The aircraft was configured and we were spot on the the GS. I believe the pilot flying disconnected the AP at 800'. The pilot flying had a perfect PAPI indication. At approximately 400' (visual; day conditions) we got two 400' ft calls (obvious reason for the dips in terrain) and then the EGPWS went berserk. VOL 2 memory items say for day; VMC conditions; you may consider the information cautionary. The GPWS was still going off on the ground during roll out.  I talked to dispatch and maintenance control about it immediately after the flight. Dispatch had no information regarding any published terrain alerts for RWY 32 or any reason not to land on 32. Nothing in our [manual]. Conferring with maintenance; the opinion was that the radio altimeter antenna accumulated ice or was weather sensitive with the fluctuation of temperature in and out of the clouds and the moderate rain conditions. Referencing OEB XXX-X; I believe this to be the case also.I don't believe this event is something that can be prevented. I would probably advise landing on 28L where there are less variations in the terrain prior to the runway threshold unless crosswind limitations preclude it. I am not sure if the variations in terrain prior to RWY 32 played a factor in the alert; but it probably exacerbated the situation.


Second narrative: [Report narrative contained no additional information.]


Synopsis: A320 flight crew reported that during landing with glideslope captured they received a GPWS warning and it continued after landing.