A B737-300 AUTOPLT PITCHED UP TO CAPTURE THE GS CAUSING THE FO TO EXECUTE STALL RECOVERY PROCS BECAUSE OF THE RAPID AIRSPD LOSS.

Narrative

DURING APCH VECTOR TO LOC WHILE AUTOPLT COUPLED WITH APCH SELECTED; ACFT PITCHED UP TO CAPTURE GS. AIRSPD QUICKLY SLOWED TO BELOW MANEUVER SPD FOR CONFIGN. FO FLYING DISCONNECTED AUTOPLT AND RECOVERED. FLAPS WERE EXTENDED TO SPD RETURN TO CORRECT CONFIGN. APCH CONTINUED MANUALLY TO VFR LNDG. DIGITAL ATIS RPTED 'ILS RWY 23 GS UNUSABLE BEYOND 5 DEGS R OF COURSE;' HOWEVER; APCH VECTORED US ON R DOWNWIND; VECTORED TO INTERCEPT HDG AND CLRED US FOR APCH. EVERYTHING APPEARED NORMAL ON THE INSTS WITH IDENT CHK. SITUATION WAS INTERMITTENT SNOW CLOUDS WITH RWY IN SIGHT ON DOWNWIND. CLOUDS ON FINAL CAUSED US TO CONTINUE INST APCH RATHER THAN DECLARE VISUAL. CONDITIONS WERE RELAXED WITH THE EXPECTATION OF A VISUAL LNDG TO A GROOMED RWY. I WAS LOOKING L AT THE GND TO DETERMINE STREET CONDITIONS WITH BANK OF ABOUT 10-15 DEGS R AND DID NOT FEEL THE PITCH UP OR SLOW DOWN. WHEN I RETURNED ATTN TO INSTS; FO WAS ALREADY MAKING CORRECTIVE ACTIONS. SPD WAS ABOUT 181 KTS IN CLEAN CONFIGN. FO FOLLOWED STALL RECOVERY PROCS AND ACFT WAS QUICKLY RETURNED TO NORMAL FLT. I SHOULD HAVE GIVEN MORE THOUGHT TO THE ATIS INFO. A MANUALLY FLOWN APCH WOULD HAVE BEEN APPROPRIATE UNDER THE CONDITIONS. MY ATTN SHOULD HAVE BEEN DIRECTED TO THE ILS CAPTURE WITH GND CONDITIONS DETERMINED EARLIER DURING DOWNWIND. I WAS STARTLED WITH THE RAPID DETERIORATION FROM NORMAL AIRSPD. THIS TYPE OF ATIS INFO COULD HAVE BEEN INCLUDED IN THE WX PACKAGE BUT WAS NOT.