HIGH LEVEL WIND SHEAR ENCOUNTER. TEMPORARY LOSS OF ACFT CTL.

Narrative

A FAST MOVING COLD FRONT WAS JUST PASSING OUT OF THE DFW- TXK-ACT AREA MOVING IN A SE DIRECTION EXTENDING ALONG TX; ARK; LA AREAS. WE PICKED OUR WAY AROUND THE FRONT COMING IN FROM THE BACK SIDE ON OUR WAY TO MIA. AS WE LEVELED OFF AT FL370; NO STORMS WERE ABOVE US AND WE COULD SEE THE LINE BELOW US WITH MOST OF THE ACTIVITY TO OUR R. WE WERE VECTORED TOWARD LFK AND THEN TO PROCEED OVER MSY AND OUT OVER THE GULF TO MIA. AT ABOUT THE 295R FROM MSY AT ABOUT 210 MI FROM MSY; THE ACFT SUDDENLY; WITH AUTOPLT ON; SWUNG INTO A 35-45 DEGS R BANK; LOST 600-700 FT ALT AND OUR AIRSPD DROPPED FROM 280-290 KIAS TO 205 KIAS ALL IN LESS THAN 5 SECONDS. WE HEARD STALL BUFFET GOING OVER OUR WINGS FOR AT LEAST 20-30 SECONDS. THE ACFT PITCHED UP TO A PLUS 400 FT OVER FL370; AIRSPD WOULD NOT RECOVER AND BANK WAS STILL OSCILLATING BACK AND FORTH ABOUT 15-20 DEGS. WE IMMEDIATELY REQUESTED LOWER; WERE GIVEN FL330 AND AS WE DSNDED; ACFT'S STABILITY RETURNED. NO PAX NOR FLT ATTENDANTS WERE INJURED AT ANY TIME. I HAD SAT EVERYONE DOWN WELL BEFORE WE ENCOUNTERED THIS SIT. I NOTIFIED ATC AND DISPATCH. OTHER ACFT ESPECIALLY ONE AT FL410 RPTED SIMILAR PROBS. THE REST OF THE FLT WAS UNEVENTFUL. I FEEL THAT WITH THIS COLD FRONT HITTING THE WARM MOIST GULF AIR; WE EXPERIENCED HIGH ALT WIND SHEAR. SUPPLEMENTAL INFO FROM ACN 294483: WE NOTIFIED ATC AND OPS TO INSURE OTHER ACFT WOULD AVOID THE AREA WE HAD ENCOUNTERED HIGH ALT WIND SHEAR INDICATIONS.