Jun 5, 2010 0600 UTC Day 1 Convective Outlook
Updated: Sat Jun 5 08:44:24 UTC 2010
Probabilistic to Categorical Outlook Conversion Table
Public Severe Weather Outlook

The SPC is forecasting ...severe thunderstorms expected over parts of the mid mississippi and ohio valleys this afternoon and tonight....   Please read the latest public statement about this event.

Categorical Graphic
20100605 1200 UTC Day 1 Outlook Graphic
Probabilistic Tornado Graphic
20100605 1200 UTC Day 1 Tornado Probabilities Graphic
Torndao Legend Image
Probabilistic Damaging Wind Graphic
20100605 1200 UTC Day 1 Damaging Wind Probabilities Graphic
Wind Legend Image
Probabilistic Large Hail Graphic
20100605 1200 UTC Day 1 Large Hail Probabilities Graphic
Hail Legend Image
   SPC AC 050549
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1249 AM CDT SAT JUN 05 2010
   
   VALID 051200Z - 061200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS IN EXTREME SE IA...EXTREME NE
   MO...NRN/CNTRL PARTS OF IL/IND AND NW OH...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE NERN/MID-ATLANTIC
   STATES TO THE MID/UPPER MS VALLEY...
   
   ...SYNOPSIS...
   FAST ZONAL FLOW OVER THE NRN-HALF OF THE COUNTRY WILL BUCKLE OVER
   THE UPPER MS VALLEY BY SATURDAY NIGHT AS A STRONG JET STREAK
   TRANSLATES RAPIDLY EWD FROM THE NRN ROCKIES.  TO THE SOUTH...AN
   ELONGATING UPPER LOW OVER THE CNTRL/WRN GULF STATES WILL REMAIN IN
   PLACE.
   
   ...UPPER MS VLY EWD ACROSS THE MIDWEST/UPPER OH VALLEY...
   A WEAK IMPULSE MOVING EWD ACROSS THE CORN BELT EARLY THIS MORNING
   WAS ENHANCING THUNDERSTORMS AND CLUSTERS OF STORMS WILL BE ONGOING
   AT 12Z OVER PARTS OF IA AND NRN IL.  MAINTENANCE OF ROUGHLY 40-45 KT
   OF UNIDIRECTIONAL WSW MID-LEVEL FLOW ATTENDANT TO THIS IMPULSE AND
   STRONG HEATING OF AN AMPLY MOIST BOUNDARY LAYER WILL LIKELY
   CONTRIBUTE TO A CONTINUED SEVERE RISK ACROSS CNTRL/NRN PARTS OF
   IND/OH THROUGH THE AFTERNOON. 
   
   ATTENTION WILL THEN FOCUS UPSTREAM DURING THE MID-LATE AFTERNOON
   AHEAD OF THE AMPLIFYING UPPER TROUGH AND RECOVERING AIR MASS IN WAKE
   OF MORNING STORMS.  SURFACE DEW POINTS IN EXCESS OF 70F...PRESENCE
   OF 50-55 KTS OF DEEP LAYER SHEAR...INCREASING LARGE SCALE ASCENT AND
   REBOUNDING MID-LEVEL LAPSE RATES WILL FOSTER SUPERCELLS AS ACTIVITY
   INITIATES OVER CNTRL/ERN IA.  LARGE HAIL AND A FEW TORNADOES ARE
   LIKELY.  AS WLY FLOW INCREASES ALONG THE BASE OF THE
   TROUGH...ACTIVITY WILL TRANSITION INTO A BOWING MESOSCALE SYSTEM
   WITH EMBEDDED SUPERCELLS AND ACCELERATE DOWNSTREAM INTO CNTRL/NRN
   IL...CNTRL/NRN IND AND POSSIBLY PARTS OF NWRN OH ALONG/S OF AN E-W
   ORIENTED BAROCLINIC ZONE BY EVENING.  ALL FACETS OF SEVERE WEATHER
   CAN BE ANTICIPATED WITH VERY STRONG DAMAGING WIND GUSTS...LARGE HAIL
   AND A FEW TORNADOES.
   
   WHILE LEADING STORMS WILL FORWARD-PROPAGATE INTO THE UPPER OH VALLEY
   OVERNIGHT...THERMODYNAMIC/KINEMATIC SET-UP WILL FAVOR BACKBUILDING
   STORMS ALONG THE SURGING COLD FRONT/OUTFLOW INTO NERN MO AND CNTRL
   IL OVERNIGHT WITH AT LEAST ISOLATED RISKS FOR HIGH WINDS/HAIL.
   
   ...NERN STATES...
   CONSIDERABLE CONVECTION WILL MOVE ACROSS THE NERN STATES EARLY
   SATURDAY BUT WILL PROBABLY CLEAR THE REGION IN TIME FOR AFTERNOON
   HEATING.  MOIST BOUNDARY LAYER AND ANTICIPATED HEATING WILL
   CONTRIBUTE TO MLCAPES AROUND 1000-1500 J/KG.  AS THE IMPULSE OVER
   THE GREAT LAKES REGION MOVES OVER THE REGION BY LATE
   AFTERNOON...WIDELY SCATTERED THUNDERSTORMS WILL DEVELOP OVER ERN
   NY/WRN NEW ENGLAND.  ENVIRONMENT WILL BE STRONGLY SHEARED WITH 55
   KTS OF 0-6KM SHEAR AND BRIEF SUPERCELLS MAY RESULT WITH LARGE HAIL
   AND ISOLATED TORNADOES.  ACTIVITY WILL MOVE TOWARD THE COAST DURING
   THE EVENING WITH RISKS FOR PRIMARILY DAMAGING WINDS.
   
   ...MID-ATLANTIC...  
   AT LEAST ISOLATED...DIURNALLY-ENHANCED THUNDERSTORMS WILL DEVELOP
   ALONG THE LEE TROUGH/HIGHER TERRAIN OF SERN PA AND WRN MD/VA ON
   SATURDAY.  REGION WILL REMAIN ALONG SRN PERIPHERY OF 30-40 KTS OF
   WLY MID-LEVEL FLOW...FAVORABLE FOR MULTICELL STORMS CAPABLE OF
   DAMAGING WINDS/HAIL.
   
   ...ERN CO...
   ISOLATED THUNDERSTORMS WILL FORM ALONG THE HIGHER CO TERRAIN AS ENE
   UPSLOPE FLOW TRANSPORTS IMPROVING LOW-LEVEL MOISTURE ACROSS THE HIGH
   PLAINS BEHIND A COLD FRONT. AN ISOLATED HIGH-BASED SUPERCELL STORMS
   WITH LARGE HAIL/LANDSPOUT WILL BE POSSIBLE IN THE VICINITY OF THE
   PALMER DIVIDE...DIMINISHING DURING THE EVENING.
   
   ...NRN PLAINS...
   A FEW STRONG/ISOLATED SEVERE THUNDERSTORMS CAN BE EXPECTED SATURDAY
   AFTERNOON/EVENING AS MID-LEVEL COLD POCKET ASSOCIATED WITH THE
   AMPLIFYING TROUGH SPREADS ATOP RESIDUAL 50S SURFACE DEW POINTS. 
   PRIMARY THREAT WILL BE MARGINALLY SEVERE HAIL AND SHOULD DIMINISH
   AFTER SUNSET.
   
   ...FL...
   ANOTHER ROUND OF THUNDERSTORMS WILL DEVELOP ALONG SEA
   BREEZES...FAVORING THE INTERIOR AND EAST COAST.  FORECAST SOUNDINGS
   EXHIBIT COMPARATIVELY DRIER MID-LEVEL ENVIRONMENT OVER FRIDAY.  THIS
   MAY YIELD AT LEAST ISOLATED PULSE SEVERE STORMS WITH DAMAGING WIND
   GUSTS.
   
   ..RACY/SMITH.. 06/05/2010
   
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   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1300Z