Jul 27, 2010 1630 UTC Day 1 Convective Outlook
Updated: Tue Jul 27 16:29:43 UTC 2010
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20100727 1630 UTC Day 1 Outlook Graphic
Probabilistic Tornado Graphic
20100727 1630 UTC Day 1 Tornado Probabilities Graphic
Torndao Legend Image
Probabilistic Damaging Wind Graphic
20100727 1630 UTC Day 1 Damaging Wind Probabilities Graphic
Wind Legend Image
Probabilistic Large Hail Graphic
20100727 1630 UTC Day 1 Large Hail Probabilities Graphic
Hail Legend Image
   SPC AC 271626
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1126 AM CDT TUE JUL 27 2010
   
   VALID 271630Z - 281200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE UPR MS VLY
   AND UPR GRT LKS...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS OVER PARTS OF THE SOUTHEAST...
   
   ...UPR MS VLY/UPR GRT LAKES...
   AS A VERY MOIST AND UNSTABLE AIR MASS CONTINUES TO SURGE NEWD ACROSS
   MN/WI INTO UPR GRT LAKES THIS AM...CONDITIONS STILL ON TRACK FOR A
   POTENTIALLY VERY ACTIVE SEVERE THUNDERSTORM EVENT.  WITH THE STRONG
   TROUGH NOW SCENTRAL CANADA CONTINUING TO TRANSLATE EWD...WIND
   PROFILES IN SUPPORT OF ORGANIZED SEVERE THUNDERSTORMS INCLUDING
   SUPERCELLS WILL BE IN PLACE THIS AFTERNOON/EVENING FROM CENTRAL/NRN
   MN EWD ACROSS NRN WI INTO THE UP OF MICHIGAN.
   
   CONSIDERED AN UPGRADE TO MDT ACROSS NRN WI INTO THE UP OF MI FOR
   LATER THIS AFTERNOON AS THE STRONG WIND MAX WITH THE UPR TROUGH
   ROTATES ACROSS...HOWEVER THERE IS STILL A CONCERN AS TO HOW THE
   ONGOING ELEVATED STRONG/SEVERE THUNDERSTORMS WILL IMPACT THE
   DESTABILIZATION PROCESS NWD INTO WI.  FOCUS FOR SURFACE BASED SEVERE
   DEVELOPMENT...I.E. POTENTIAL FOR TORNADIC SUPERCELLS...DEPENDENT ON
   THE BOUNDARIES THAT WILL EVOLVE FROM THIS MORNING CONVECTION.  GIVEN
   MLCAPES UPWARDS TO 4000 J/KG IN THE WARM SECTOR AND AT LEAST 30-40
   KT OF SHEAR...THERE IS THE POTENTIAL FOR STRONG TORNADOES WITH ANY
   SUPERCELL THAT DEVELOPS BY LATER THIS AFTERNOON.  WILL KEEP OPTION
   OPEN OF AN UPGRADE TO MDT IN 20Z OUTLOOK IF THE BOUNDARY LAYER IN
   FACT CAN RECOVER FAR ENOUGH N IN WI TO BECOME INVOLVED WITH THE
   STRONGER UPPER SUPPORT AND WIND FIELDS ASSOCIATED WITH THE TROUGH
   MOVING ACROSS SK/MB INTO WRN ONTARIO THIS EVENING.
   
   FARTHER SW...FROM SW MN INTO SD/NRN NEB...WARM TEMPERATURES ALOFT
   LIKELY WILL CAP AREAS ALONG/AHEAD OF COLD FRONT UNTIL LATE IN THE
   DAY. STRONG/SVR TSTMS SHOULD...HOWEVER...FORM IN RESPONSE TO STRONG
   HEATING AND LOW LVL UPLIFT ALONG STRENGTHENING FRONT.  WHILE DEEP
   SHEAR WILL BE WEAKER IN THIS REGION RELATIVE TO POINTS N...IT SHOULD
   BE SUFFICIENT FOR MULTICELLS AND SOME SUPERCELLS WITH LARGE
   HAIL/DMGG WIND.
   
   ULTIMATELY...AS MAIN SYNOPTIC COLD FRONT OVERTAKES LEAD BOUNDARY AND
   CONTINUES SEWD...STORMS OVER THE UPR MS VLY SHOULD ASSUME A QLCS
   STRUCTURE.  THE BAND AND ITS EMBEDDED BOWING SEGMENTS LIKELY WILL
   EXTEND FROM UPR MI WSW INTO SRN MN/NRN IA AND SE SD LATE TONIGHT.
   THE SVR THREAT...MAINLY FROM DMGG WIND...MAY PERSIST THROUGH EARLY
   WED IN WI AND MI...WHERE STRONGEST FORCING FOR ASCENT WILL EXIST.
   
   ...TN VLY/SRN APPALACHIANS/CAROLINA'S...
   LITTLE CHANGE IN THINKING THIS AREA AS A MOIST/POTENTIALLY UNSTABLE
   AIR WILL PERSIST INVOF REMNANT FRONT STALLED ROUGHLY NW/SE ACROSS
   REGION.  TSTM COVERAGE/INTENSITY SHOULD INCREASE NEAR THE BOUNDARY
   THROUGH THE AFTN.  COUPLED WITH BELT OF MODEST WNW FLOW ALOFT /15-20
   KT AT 500 MB/...POCKETS OF 2000-2500 J/KG SBCAPE MAY SUPPORT SOME
   MULTICELL CLUSTERS CAPABLE OF LOCALLY DMGG WIND THROUGH EARLY EVE.
   
   ...NRN RCKYS/INTERMOUNTAIN REGION...
   UPR RIDGE EXPECTED TO BUILD N ACROSS THE GRT BASIN/NRN INTERMOUNTAIN
   REGION TODAY...WHILE WRN PART OF COLD FRONT ASSOCIATED WITH SK/MB
   UPR TROUGH SETTLES S ACROSS PARTS OF ID/MT. LOW LVL MOISTURE
   SPREADING WWD INTO REGION IN WAKE OF FRONT... PRESENCE OF 30 KT SW
   TO WSWLY FLOW ON NRN FRINGE OF RIDGE...AND TERRAIN UPLIFT MAY
   SUPPORT A FEW SMALL CLUSTERS OF STORMS WITH GUSTY WINDS AND
   MARGINALLY SVR HAIL THIS AFTN AND EARLY EVE.
   
   ..HALES/ROGERS.. 07/27/2010
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 2000Z