Jun 25, 2010 0600 UTC Day 1 Convective Outlook
Updated: Fri Jun 25 09:14:45 UTC 2010
Probabilistic to Categorical Outlook Conversion Table
Public Severe Weather Outlook

The SPC is forecasting ...severe thunderstorms expected over parts of the northern plains to upper mississippi valley later today and tonight....   Please read the latest public statement about this event.

Categorical Graphic
20100625 1200 UTC Day 1 Outlook Graphic
Probabilistic Tornado Graphic
20100625 1200 UTC Day 1 Tornado Probabilities Graphic
Torndao Legend Image
Probabilistic Damaging Wind Graphic
20100625 1200 UTC Day 1 Damaging Wind Probabilities Graphic
Wind Legend Image
Probabilistic Large Hail Graphic
20100625 1200 UTC Day 1 Large Hail Probabilities Graphic
Hail Legend Image
   SPC AC 250551
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1251 AM CDT FRI JUN 25 2010
   
   VALID 251200Z - 261200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS FROM SRN MN...EXTREME NRN IA
   INTO WI...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NRN PLAINS...UPPER MS
   VALLEY AND UPPER GREAT LAKES...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS OVER A PORTION OF THE
   CAROLINAS...
   
   ...SYNOPSIS...
   
   LARGE SCALE PATTERN WILL REMAIN DOMINATED BY A LOW AMPLITUDE UPPER
   RIDGE OVER THE NRN PLAINS AND A TROUGH ADVANCING THROUGH THE WRN
   STATES. IMPULSE CURRENTLY MOVING THROUGH SRN SASKATCHEWAN WILL TURN
   ESEWD TODAY INTO SRN ONTARIO AND NRN MN AS IT CRESTS UPPER RIDGE.
   THIS FEATURE WILL FORCE A SURFACE BOUNDARY SEWD THROUGH THE NRN
   PLAINS AND UPPER MS VALLEY DURING THE AFTERNOON. ANOTHER SHORTWAVE
   TROUGH NOW APPROACHING THE PACIFIC NW WILL MOVE THROUGH THE NRN
   ROCKIES...REACHING THE NRN HIGH PLAINS LATER FRIDAY NIGHT. FARTHER
   SOUTH A REMNANT FRONTAL BOUNDARY WILL PERSIST FORM THE CAROLINAS WWD
   THROUGH THE TN VALLEY AREA.
   
   
   ...NRN PLAINS THROUGH UPPER MS VALLEY AND GREAT LAKES...
   
   THE IMPULSE MOVING ESEWD THROUGH S-CNTRL CANADA WILL FORCE A WEAK
   FRONT SEWD THROUGH THE NRN PLAINS TODAY WHILE A CONVECTIVELY
   REINFORCED E-W BOUNDARY PERSISTS FROM NRN MN EWD INTO NRN WI. THE
   SWLY LOW LEVEL JET WILL VEER AND SHIFT EWD THROUGH THE UPPER MS
   VALLEY IN RESPONSE TO THE PROGRESSIVE SHORTWAVE TROUGH. THIS FEATURE
   WILL TRANSPORT HIGHER THETA-E AIR NEWD THROUGH THE WARM SECTOR
   BENEATH STEEP MID LEVEL LAPSE RATES RESULTING IN 2000-2500 J/KG
   MLCAPE. A FEW STORMS MAY STILL BE ONGOING PRIMARILY NORTH OF
   BOUNDARY ACROSS NRN MN AND ND AT THE START OF THIS PERIOD. THIS
   ACTIVITY WILL BE ELEVATED WITH LIMITED SEVERE POTENTIAL. OTHER
   STORMS ARE EXPECTED TO DEVELOP ALONG AND AHEAD OF SEWD ADVANCING
   BOUNDARY FROM ERN SD INTO SRN MN AS THE ATMOSPHERE DESTABILIZES AND
   THE CAP WEAKENS. BELT OF STRONGER 60-70 KT MID LEVEL FLOW ASSOCIATED
   WITH THE PROGRESSIVE IMPULSE WILL CONTRIBUTE TO 40-50 KT BULK SHEAR.
   INITIAL STORMS WILL LIKELY BE SUPERCELLULAR IN NATURE WITH A THREAT
   FOR LARGE HAIL. WITH THE LOW LEVEL JET EXPECTED TO VEER WITH
   TIME...0-1 KM HODOGRAPHS WILL NOT BE PARTICULARLY LARGE...BUT
   SUFFICIENT TO SUPPORT A THREAT FOR ISOLATED TORNADOES THROUGH EARLY
   EVENING. STORMS ARE EXPECTED TO EVENTUALLY GROW UPSCALE TO AN MCS
   WITH AN INCREASING THREAT FOR WIDESPREAD DAMAGING WIND MAINLY
   THROUGH SRN MN...NRN IA AND WI.
   
   FARTHER UPSTREAM ACROSS THE CNTRL AND NRN PLAINS...EXTENT OF SEVERE
   THREAT IS MORE UNCERTAIN DUE TO POTENTIAL FOR A STRONGER CAP AND
   PRESENCE OF UPPER RIDGE. POST FRONTAL ELY UPSLOPE FLOW WILL BECOME
   ESTABLISHED LATER IN THE AFTERNOON OR EVENING. STORMS MAY DEVELOP
   OVER THE HIGHER TERRAIN AND SPREAD EWD INTO THE UNSTABLE POST
   FRONTAL ENVIRONMENT WITH A THREAT FOR SUPERCELLS WITH ISOLATED LARGE
   HAIL. OTHER STORMS MAY INCREASE IN COVERAGE DURING THE EVENING OVER
   THE HIGHER TERRAIN OF MT AS LARGE SCALE FORCING FOR ASCENT INCREASES
   DOWNSTREAM FROM ADVANCING UPPER TROUGH. THIS ACTIVITY MAY EVENTUALLY
   MOVE INTO THE NRN HIGH PLAINS OVERNIGHT WITH AT LEAST A MODEST
   THREAT FOR ISOLATED DAMAGING WIND AND HAIL.
   
   ...SERN STATES...
   
   STORMS ARE EXPECTED TO ONCE AGAIN DEVELOP IN VICINITY OF STALLED
   BOUNDARY FROM THE CAROLINAS WWD INTO THE TN VALLEY AND SERN STATES.
   DESPITE WEAK VERTICAL SHEAR...STRONG INSTABILITY WILL SUPPORT A
   THREAT FOR WET MICROBURSTS DURING THE AFTERNOON. HAVE INTRODUCED A
   SLIGHT RISK OVER THE CAROLINAS WHERE THE ATMOSPHERE WAS NOT
   OVERTURNED BY CONVECTION ON THURSDAY AND WHERE THE FRONT MAY RESULT
   IN A GREATER CONCENTRATION OF STORMS AND SEVERE EVENTS.
   
   ..DIAL/DEAN/JEWELL.. 06/25/2010
   
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   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z