THE FLC OF A B737-300 HAD A GPWS ALERT VOICE WARNING OF 'TOO LOW' DURING A VISUAL APCH ON A LONG LOW FINAL TO LAX RWY 24R BELOW THE OVCST AND IN OCCASIONAL RAIN SHOWERS. HOWEVER; THE GND WAS VISIBLE AND THEY COULD SEE NO IMMEDIATE DANGER TO TAKE EVASIVE ACTION. THEY HAD JUST TURNED OFF OF AN EXTENDED DOWNWIND VECTOR.

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2 SEPARATE GPWS WARNINGS OCCURRED WHILE MANEUVERING ON RADAR VECTORS FOR THE ILS RWY 24R AT LAX. BOTH OCCURRED WHILE IN LEVEL FLT AT 2500 FT MSL (MVA); AND I WAS HAND FLYING THE ACFT (B737-300). CONDITIONS WERE NIGHT IMC WITH SCATTERED RAIN SHOWERS; AND WE WERE JUST BELOW THE CEILING; WHICH WAS ABOUT 3000 FT BROKEN TO OVCST. THE FIRST WARNING; 1 CYCLE OF 'TOO LOW GEAR' OCCURRED WHILE THE ACFT ENTERED A HVY RAIN SHOWER AND ON AN EXTENDED DOWNWIND NE OF THE LOC ON A HDG OF 100 DEGS. THE SECOND WARNING; 1 CYCLE OF 'TERRAIN TERRAIN' OCCURRED AT 22.0 - 21.5 DME OF IGSS (RWY 24R LOC) WHILE ESTABLISHED ON THE LOC; ONCE AGAIN IN A HVY RAIN SHOWER. IN BOTH INSTANCES TERRAIN (HILLS -- I BELIEVE TO BE THE HOLLYWOOD HILLS WITH A MAX HT OF 1400 FT MSL) WERE VISIBLE. ACFT WAS HAND FLOWN +/-100 FT (DUE TO TURB) OF 2500 FT MSL IN BOTH INSTANCES. I BELIEVE BOTH WARNINGS WERE FALSE (AS OUTLINED IN OUR FLT MANUAL) DUE TO THE HVY RAIN SHOWERS. I WANTED TO ALERT YOU; THOUGH; IN CASE THERE IS ANY PROB WITH THE MVA. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR STATED THAT SINCE THE TERRAIN WAS VISIBLE UNDERNEATH THE ACFT; AND THE GPWS ALERT WAS OF A SHORT DURATION; THERE DID NOT APPEAR TO BE A NEED FOR EVASIVE ACTION. HOWEVER; THE CREW DID ADVISE ATC OF THEIR WARNING AND ATC RESPONDED WITH THE FACT THAT 2500 FT WAS THE MVA FOR THE AREA IN WHICH THEY WERE LOCATED. ATC ALSO ADDED THAT THEY HAD NOT BEEN ABLE TO TURN THEM INBOUND EARLIER DUE TO TFC. RPTR SUGGESTED THAT ATC EITHER RAISE THE VECTORING ALT IN THE AREA OF QUESTION OR ASSURE THAT A TURN INBOUND IS MADE EARLIER.