TAILWHEEL ACFT FLIPS OVER WHILE TAXIING WITH A GUSTING CROSS AND TAILWIND.

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AFTER MAKING 5 PRACTICE LNDGS AND TKOFS FROM RWY 32; (WIND NW 320 DEGS; LIGHT TO MODERATE WITH SOME STRONGER GUSTS); FLEW W 2-3 MI TO TAKE PICTURES OF A BOAT YARD AND RETURNED AND LANDED ON RWY 32. AFTER TAXIING ABOUT 1000 FT TO THE INTXN OF RWY 25/7; I COMMENCED A 180 DEG TURN TO ENTER THE TXWY FOR RWY 32. BTWN 1/4 TO 1/2 WAY INTO THE TURN A GUST OF WIND LIFTED THE R WING AND SIMULTANEOUSLY BEGAN LIFTING AND TURNING THE TAIL TO THE L. I ADDED A BURST OF PWR TO GAIN MORE CTL OF THE RUDDER AND HORIZ STABILIZER; SINCE THE ACFT WAS MOVING SLOWLY AS I INITIATED THE XWIND TURN; PULLED THE STICK FULLY BACK; APPLIED MORE L RUDDER AND APPLIED FULL DOWN AILERON ON THE R SIDE TO TRY TO LOWER THE RISING R WING. WHILE THE TAIL RESPONDED TO CTL INPUT AND BEGAN TO MOVE TO THE R AND REALIGNING THE NOSE WITH THE ENTRANCE OF THE TXWY; THE R WING CONTINUED AT A HIGH ATTITUDE NOT RESPONDING TO CTL SURFACE INPUT. THE EVER CHANGING WIND ANGLE IN RELATION TO THE ACFT AS IT TURNED BECAME 'CRITICAL.' (IN ATTEMPTING TO CORRECT THE SIT DESCRIBED ABOVE; THE RADIUS OF THE INTENDED TURN HAD INCREASED AND INTENDED DIRECTION AND SPD HAD CHANGED RESULTING IN THE SUBSEQUENT DAMAGE TO THE ACFT.) THE ACFT AT THIS POINT; EXITED THE RWY (RWY 25) SLIGHTLY TO THE R OF THE INTENDED TXWY ENTRANCE WHERE THE L MAIN GEAR IMPACTED THE SNOW AND ICE BUILD-UP FROM RECENT SNOW STORM PLOWING; CAUSING ME TO INADVERTENTLY APPLY PWR DUE TO THE SUDDEN IMPACT! THE ACFT BECAME AIRBORNE FOR 3-5 FT; AS DETERMINED BY THE WHEEL MARKS IN THE SNOW; AND SETTLED INTO 6-8 INCHES OF PACKED SNOW; THE WINGS WERE FINALLY LEVEL; BUT THE COMBINATION OF FORWARD MOMENTUM AND RESTRICTING SNOW CAUSED THE ACFT TO FLIP OVER -- WITH THE NOW EFFECTIVE TAILWIND AIDING THE PROCESS. THE ACFT SETTLED UPSIDE DOWN WITH THE VERT STABILIZER SMASHING ONTO THE ONLY OBSTRUCTION AROUND; THE RWY 32 TAXI/RWY 7/25 IDENT SIGN BOX! THE PROP WAS CURVED BACKWARD ALMOST SYMMETRICALLY SINCE THE ENG CONTINUED TO RUN UNTIL THE ACFT WAS ALMOST INVERTED. SEEING SOME FUEL BEGIN TO LEAK FROM THE TANK IN FRONT OF ME; I RELEASED THE 3-POINT SHOULDER HARNESS AND BELT; DROPPED TO THE CEILING OF THE ACFT; OPENED THE WINDOW/DOOR AND CRAWLED OUT OF THE ACFT UNINJURED. I REACHED INTO THE ACFT FROM OUTSIDE AND TURNED THE MAGNETO SWITCH AND FUEL FLOW LEVER TO OFF POS. IN RETROSPECT; WITH MY 300+ HRS OF TAILWHEEL EXPERIENCE; I SHOULD HAVE BETTER ANTICIPATED: 1) THE POSSIBILITY OF STRONGER WIND GUSTS DURING THE REQUIRED 180 DEG TURN TO THE TXWY AND THE PROBABLE EFFECT ON THE STABILITY OF THE ACFT THROUGHOUT THE TURN. 2) THE POSSIBILITY OF THE SNOW BANKS; N OF INTENDED TURN; AFFECTING THE WIND PATTERN AND POSSIBLE VENTURI EFFECT OF BANKS ON THE WIND PATTERN AND VELOCITY WIND BLOWING OVER THEM ONTO THE RWY/TXWY AREA IN QUESTION. 3) 'ALLOWING' THE ACFT TO 'WEATHER VANE' FULLY INTO THE CTRLINE OF RWY 25; INSTEAD OF ADDING PWR; MANIPULATING THE CTLS; ETC; TO TRY TO REGAIN MY INTENDED TRACK TOWARD THE TXWY. (MY INSTINCT; HOWEVER; INSTILLED MY CONTINUOUS PLT TRAINING AND PROFICIENCY RETRAINING -- HAVE LEVEL VIII FAA PLT PROFICIENCY WINGS -- WAS TO REGAIN CTL OF THE ACFT AND NOT JUST TAKE AN UNCTLED RIDE IN IT!) IN RECALLING THE EVENT; I MUST SAY THAT MY THOUGHTS AND CONCERN AT THE TIME WAS TO KEEP THE ACFT L WING FROM STRIKING THE GND OR POSSIBLY OVERTURNING ALTOGETHER WHEN THE TAIL BEGAN TO LIFT AS WELL. THE FINAL OUTCOME SIMPLY WAS NEVER CONSIDERED. IF I HAD CONTINUED TO THE HANGAR ON THE N SIDE OF THE ARPT AND PUT THE ACFT AWAY WITHOUT REFUELING (AS IS CONTRARY TO OUR CLUB'S CUSTOM) AND NOT MAKE THE TURN TO THE FUEL PUMPS ON THE S SIDE OF THE FIELD; THIS INCIDENT WOULD NOT HAVE OCCURRED. UNFORTUNATELY; WE HAVE NO 'CRYSTAL BALL' (ON INST PANEL).