SPC AC 150729

   DAY 3 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0229 AM CDT SUN SEP 15 2013

   VALID 171200Z - 181200Z

   ...NO SVR TSTM AREAS FORECAST...

   ...SYNOPSIS...
   STRENGTHENING/AMPLIFYING WESTERLIES ARE EXPECTED OVER THE NORTHWEST
   QUADRANT OF THE CONUS ON TUESDAY...WITH A CONSIDERABLE UPPER TROUGH
   EXPECTED TO SPREAD EAST-NORTHEASTWARD OVER THE PACIFIC
   NORTHWEST/NORTHERN INTERMOUNTAIN REGION.

   ...MT AND ADJACENT INTERMOUNTAIN REGION/WESTERN DAKOTAS...
   APPRECIABLE HEIGHT FALLS/FORCING FOR ASCENT ARE EXPECTED TO
   OVERSPREAD THE REGION ESPECIALLY TUESDAY AFTERNOON INTO TUESDAY
   NIGHT IN ASSOCIATION WITH THE AFOREMENTIONED UPPER TROUGH. CURRENT
   THINKING IS THAT STORMS WILL INITIALLY DEVELOP OVER THE HIGHER
   TERRAIN/DIVIDE VICINITY OF MT TUESDAY AFTERNOON...WITH SUBSEQUENT
   DEVELOPMENT/PERSISTENCE INTO ADDITIONAL PARTS OF EASTERN MT TUESDAY
   EVENING. THE BOUNDARY LAYER WILL NOT BE PARTICULARLY MOIST OR
   UNSTABLE...BUT ADEQUATE MOISTURE/STEEPENING LAPSE RATES SHOULD ALLOW
   FOR SOME STRONGER/POSSIBLY SEVERE TSTMS BY TUESDAY AFTERNOON. AMID
   STRENGTHENING MID-LEVEL SOUTHWESTERLY WINDS...VERTICAL SHEAR SHOULD
   BE SUFFICIENT /35-40 KT DEEP LAYER/ FOR SOME ORGANIZED STORMS
   POTENTIALLY INCLUDING A FEW SUPERCELLS/SUSTAINED LINEAR
   SEGMENTS...WITH SEVERE HAIL/WIND POSSIBLE.

   SUBSEQUENT OUTLOOKS WILL ALSO REEVALUATE THE NEED OF POSSIBLE LOW
   SEVERE PROBABILITIES ACROSS ADDITIONAL PORTIONS OF THE CENTRAL
   ROCKIES/EASTERN GREAT BASIN.

   ..GUYER.. 09/15/2013

   CLICK TO GET WUUS03 PTSDY3 PRODUCT

   NOTE: THE NEXT DAY 3 OUTLOOK IS SCHEDULED BY 0730Z