May 23, 2013 0100 UTC Day 1 Convective Outlook
Updated: Thu May 23 01:05:36 UTC 2013
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20130523 0100 UTC Day 1 Outlook Graphic
Probabilistic Tornado Graphic
20130523 0100 UTC Day 1 Tornado Probabilities Graphic
Probability of a tornado within 25 miles of a point.
Hatched Area: 10% or greater probability of EF2 - EF5 tornadoes within 25 miles of a point.
Probabilistic Damaging Wind Graphic
20130523 0100 UTC Day 1 Damaging Wind Probabilities Graphic
Probability of damaging thunderstorm winds or wind gusts of 50 knots or higher within 25 miles of a point.
Hatched Area: 10% of greater probability of wind gusts 65 knots or greater within 25 miles of a point.
Probabilistic Large Hail Graphic
20130523 0100 UTC Day 1 Large Hail Probabilities Graphic
Probability of hail 1" or larger within 25 miles of a point.
Hatched Area: 10% or greater probability of hail 2" or larger within 25 miles of a point.
Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
SLIGHT 59,917 19,655,763 Baltimore, MD...Washington, DC...Syracuse, NY...Alexandria, VA...Allentown, PA...
Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
SLIGHT 59,917 19,655,763 Baltimore, MD...Washington, DC...Syracuse, NY...Alexandria, VA...Allentown, PA...
   SPC AC 230100
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0800 PM CDT WED MAY 22 2013
   
   VALID 230100Z - 231200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS FROM THE MID ATLANTIC INTO A
   PORTION OF THE NERN STATES...
   
   ...MID ATLANTIC THROUGH THE NERN STATES...
   
   ISOLATED STORMS WITH AT LEAST MARGINAL SUPERCELL STRUCTURES ARE
   MOVING EWD THROUGH NCNTRL NY. ADDITIONAL STORMS DEVELOPING OVER LAKE
   ONTARIO WILL EVENTUALLY MOVE INTO NRN NY. VERTICAL SHEAR IN THIS
   REGION IS A BIT STRONGER THAN FARTHER SOUTH WITH 30-40 KT EFFECTIVE
   SHEAR...AND THE LLJ IS FORECAST TO STRENGTHEN DURING THE EVENING.
   THREAT FOR ISOLATED LARGE HAIL AND DAMAGING WIND WILL PERSIST
   THROUGH AT LEAST MID EVENING. ALSO AN ISOLATED TORNADO CANNOT BE
   RULED OUT NEXT HOUR OR TWO.
   
   FARTHER SOUTH A BROKEN LINE OF MULTICELL STORMS EXTENDS FROM ERN PA
   SWD THROUGH WRN VA AND WRN NC. THIS ACTIVITY MAY CONTINUE TO POSE A
   THREAT FOR ISOLATED DAMAGING WIND AND LARGE HAIL THROUGH MID
   EVENING...BUT A GRADUAL DECREASE IS EXPECTED TO BEGIN BY 02Z AS THE
   BOUNDARY LAYER BEGINS TO COOL.
   
   ...OH VALLEY...
   
   WIDELY SCATTERED MOSTLY MULTICELL STORMS PERSIST ACROSS THE OH
   VALLEY SWD INTO THE TN VALLEY WITHIN MODEST BROAD CYCLONIC FLOW
   REGIME. A CONVECTIVE OUTFLOW BOUNDARY WAS ALSO OBSERVED FROM SERN KY
   THROUGH WRN WV...MOVING WWD. SOME OF THE STORMS MAY BRIEFLY ATTAIN
   SEVERE LEVELS NEXT COUPLE HOURS AS THEY INTERACT AND MERGE WITH THE
   PREEXISTING OUTFLOW BOUNDARIES. OVERALL COVERAGE OF ANY SEVERE
   REPORTS IN THIS REGION IS EXPECTED TO REMAIN SPARSE AND THE ACTIVITY
   WILL UNDERGO A GRADUAL DECREASE AS INSTABILITY DIMINISHES WITH ONSET
   OF NOCTURNAL COOLING.
   
   ..DIAL.. 05/23/2013
   
   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z