B737-500 ACFT ON APCH WAS GIVEN MICROBURST WARNING FROM TWR WHEN ON SHORT FINAL. FLC EXECUTED GAR AND TURNED R VERSUS PUBLISHED IN ORDER TO GET AROUND WX. RPTR FO HAD DIFFICULTY MAINTAINING A TWR CLRED ALT OF 2500 FT DUE TO UPDRAFT.

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AFTER HOLDING TWICE WITHIN 30 MI OF CVG; CTR HANDED US OFF TO APCH CTL. THE FIRST TIME WE HELD W AT THE ARPT BECAUSE OF TSTMS MOVING W TO E OVER THE ARPT. THE SECOND TIME WAS SE AT THE ARPT; AGAIN BECAUSE OF WX. APCH INFORMED US THAT WE WOULD BE THE FIRST ACFT IN A WHILE TO TRY AN APCH; BUT THE FIELD WAS ALSO 3500 FT BROKEN WITH OVER 6 MI VISIBILITY. WE WERE INFORMED THAT THERE HAD BEEN A MICROBURST ALERT EARLIER; BUT NO SPECIFICS. ILS FINAL TO RWY 36L WAS PERFECTLY EXECUTED UNTIL HDOF TO TWR WHOM INFORMED US THAT PREVIOUS ACFT 5-10 MINS EARLIER HAD LOST 25 KTS ON FINAL. OUR ACR REGS REQUIRE A GAR NO OPS AT A 15 KT LOSS. WE WENT AROUND AND PROCEEDING TO THE GAR ALT OF 3000 FT MSL AND INSTEAD OF TURNING INTO THE MISSED APCH DIRECTION; WE TURNED R BECAUSE OF WX. THE PROB AROSE FROM MY NOT BEING ABLE TO STOP THE CLB. THE TWR TOLD US TO CLB TO 2500 FT; BUT I WAS STRUGGLING TO KEEP IT FROM CLBING TO 3000 FT. I REACHED 3000 FT MSL AND TRIED TO DSND BUT WAS UNABLE. WITH FLUCTUATIONS IN ALT AND AIRSPD I WAS GLAD TO GAR. TWR HANDED US TO APCH; WHO WANTED A CLB TO 4000 FT MSL; AND NEITHER TWR OR APCH SAID ANYTHING. WE ENDED UP DIVERTING TO IND. THERE WERE NO OTHER ACFT ANYWHERE NEAR US. THE RADAR SHOWED MODERATE WORSE WX N AND W OF THE ARPT. ALL CTLRS SEEMED SATURATED WITH TOO MANY PLTS DEVIATING. THE FREQS WERE TOO BUSY TO TRY TO CLARIFY THE DEV. THE SAME NIGHT APR/XX/98; WE FOUND OUT THERE WERE TORNADOES N OF THE CVG ARPT. CALLBACK CONVERSATION WITH RPTR REVEALED THE FOLLOWING INFO: RPTR FO WAS ASKED ABOUT BEING UNABLE TO DSND BACK TO ASSIGNED ALT OF 2500 FT AND HE RPTS IT WAS DUE TO SEVERE UPDRAFT. RPTR SAYS THAT ACFT HAD NOT BEEN LNDG AND THAT THEIR ACFT WAS THE 'EXPERIMENTAL' APCH TO SEE IF THE WX WAS ADEQUATE. RPTR QUESTIONS WHY THE TWR GAVE A MICROBURST WARNING WHEN THEY WERE ON FINAL INSTEAD OF SOONER. IT IS LIKELY THAT THE ALERT HAD NOT OCCURRED PRIOR TO THE NOTIFICATION. RPTR'S ACR REQUIRES A GAR IF A MICROBURST WARNING IS RECEIVED ON FINAL APCH OR IF PRECEDING ACFT RPT 15 KTS OR GREATER AIRSPD LOSS. RPTR ALSO QUESTIONED WHY THE TWR CLRED THEM TO STOP CLB AT 2500 FT RATHER THAN THE PUBLISHED 3000 FT. ON THE GAR THEY FLEW A HEADING TO THE R RATHER THAN THE PUBLISHED L TURN. THE RADAR WAS PAINTED RED AND PURPLE AHEAD DURING THE GAR. PURPLE REPRESENTING TURB AND RED; A SEVERE CELL. RPTR FO WAS HAPPY THAT THE CAPT ELECTED TO DIVERT. HE RPTS THAT IT WAS ONE OF A FEW TIMES WHEN HE ACTUALLY EXPERIENCED FEAR.