May 15, 2013 1630 UTC Day 1 Convective Outlook
Updated: Wed May 15 16:41:39 UTC 2013
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20130515 1630 UTC Day 1 Outlook Graphic
Probabilistic Tornado Graphic
20130515 1630 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
20130515 1630 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
20130515 1630 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 73,053 10,341,369 Dallas, TX...Austin, TX...Ft. Worth, TX...Arlington, TX...Plano, TX...
   SPC AC 151638
   
   DAY 1 CONVECTIVE OUTLOOK CORR 1
   NWS STORM PREDICTION CENTER NORMAN OK
   1138 AM CDT WED MAY 15 2013
   
   VALID 151630Z - 161200Z
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PARTS OF TEXAS...
   
   CORRECTED FOR WORDING AT THE END OF 2ND PARAGRAPH.
   
   ...NRN AND ERN TX/SRN OK...
   COMPLEX SRN BRANCH SHORT WAVE DISTURBANCE FROM ERN NM TO W TX WILL
   DRIFT/LIFT ENEWD TDY WHILE EVOLVING INTO A CLOSED LOW CENTERED OVER
   OK BY THIS EVENING. A MOIST PLUME CHARACTERIZED BY PW VALUES AROUND
   1.5 INCHES WITHIN THE ERN QUADRANT OF THIS SYSTEM WILL CONTINUE TO
   FUEL SCATTERED TSTMS AMIDST A GRADUALLY DESTABILIZING AIRMASS ACROSS
   CNTRL AND NRN TX. BAND OF ASCENT CURRENTLY SUPPORTING POORLY
   ORGANIZED STORMS ACROSS ERN TX IS FORECAST TO CONTINUE TO DRIVE
   CONVECTION ENEWD ACROSS SERN OK AND THE ARKLATEX TODAY. AIRMASS TO
   THE EAST AND NORTHEAST OF THIS CONVECTION IS FORECAST TO REMAIN ONLY
   MARGINALLY UNSTABLE GIVEN WIDESPREAD CLOUD COVER/MARGINAL LAPSE
   RATES. DEEP SHEAR AND POCKETS OF GREATER POTENTIAL INSTABILITY OVER
   THESE AREAS MAY CONTRIBUTE TO A GRADUAL INCREASE IN SEVERE HAIL/WIND
   POTENTIAL BUT OVERALL POTENTIAL APPEARS LIMITED.
   
   A GREATER SEVERE WEATHER THREAT SHOULD EVOLVE AS THE UPPER LOW
   CONSOLIDATES ACROSS OK LATER TODAY AND A BAND OF STRONGER MID LEVEL
   WLY FLOW DEVELOPS SOUTH OF THE LOW CENTER...ACROSS THE RED RIVER
   VALLEY AND NORTH TX. THIS SHOULD OCCUR COINCIDENT WITH THE STRONGEST
   DIURNAL DESTABILIZATION EAST OF A SHARPENING DRYLINE. WEAKENING
   INHIBITION AND MLCAPE OF 1500-2000 J/KG...ALONG WITH JUXTAPOSITION
   OF MID AND HIGH-LEVEL WIND MAXIMA AND 30-35KT LLJ...WILL COMBINE TO
   SUPPORT THE DEVELOPMENT OF ORGANIZED STORMS INCLUDING SUPERCELLS
   CAPABLE OF LARGE HAIL AND A COUPLE OF TORNADOES. ACTIVITY MAY
   CONGEAL INTO ONE OR TWO SMALL SEWD MOVING MCS/S THROUGH THE EVENING
   WITH WIND DAMAGE AND LARGE HAIL POTENTIAL SPREADING ESEWD OR SEWD
   ACROSS THE I-35 CORRIDOR/DFW METROPLEX. THIS SCENARIO IS SUPPORTED
   BY HIGH PROBABILITIES FOR ORGANIZED STORMS IN THE 00Z STORM SCALE
   GUIDANCE FROM SPC SSEO AND AFWA ENSEMBLE. NOTE...00Z SSEO IS MISSING
   4KM WRF-NMM MEMBER.
   
   ...S TX...
   ROBUST STORM DEVELOPMENT IS ALSO EXPECTED OVER THE SERRANIAS DEL
   BURRO RANGE THIS AFTERNOON AIDED BY MOIST LOW-LEVEL UPSLOPE FLOW.
   STRONG INSTABILITY AND SHEAR ACROSS THE MIDDLE/LOWER RIO GRANDE
   VALLEY WILL CONTRIBUTE TO A SUPERCELL REGIME WITH ACTIVITY MOVING
   EWD/SEWD. AN INCREASED RISK FOR LARGE HAIL AND DAMAGING WINDS SHOULD
   DEVELOP OVER PARTS OF THE EDWARDS PLATEAU AND BRUSH COUNTRY THROUGH
   THE EVENING AND INTO TONIGHT. GIVEN SOMEWHAT STRONGER INHIBITION AND
   WEAKER LARGE SCALE ASCENT ACROSS THESE AREAS OF S TX...STORM
   COVERAGE MAY REMAIN ISOLATED TO WIDELY SCATTERED.
   
   ...PA/NRN WV...
   STRONG DEEP-LAYER WLY FLOW TO THE SOUTH OF A FAST MOVING SHORT WAVE
   TROUGH OVER CANADA HAS TRANSPORTED A STEEP LAPSE RATE PLUME EAST
   FROM THE PLAINS/MIDWEST. WARM SECTOR DESTABILIZATION WILL OCCUR
   AMIDST WEAK TO MODEST LARGE SCALE ASCENT AND MORE THAN ADEQUATE
   UNIDIRECTIONAL SHEAR AND LAPSE RATES FOR A FEW STRONG TO SEVERE
   STORMS. UNCERTAINTY REVOLVES AROUND CONVECTION OVERCOMING STRONG
   INHIBITION ASSOCIATED WITH THE EML PLUME/CAPPING AHEAD OF THE COLD
   FRONT SETTING INTO THE REGION LATER TONIGHT. SURFACE TEMPS WILL HAVE
   TO ATTAIN VALUES WELL INTO THE 80S F TO RESULT IN SFC-BASED STORMS
   IN THIS REGIME AND...WHILE A COUPLE OF STORMS SEEM
   POSSIBLE...OVERALL SEVERE HAIL/WIND THREAT MAY BE CONFINED TO AREAS
   IMMEDIATELY ALONG SRN PA BORDER AND NRN WV PNHDL WITH UNCERTAINTY
   INCREASING WITH EWD EXTENT.
   
   ...CNTRL PLAINS/MIDWEST...
   SURFACE FRONT TRAILING THE STRONG SHORT WAVE IN CANADA HAS SLOWED
   AND BECOME ELONGATED FROM WEST TO EAST...FROM THE KS/NEB BORDER
   ACROSS NRN MO TO THE UPPER MIDWEST. WHILE MUCH OF THE FRONTAL ZONE
   LIES SOUTH OF STRONGER MID LEVEL FLOW...SURFACE HEATING ALONG AND
   SOUTH OF THE BOUNDARY AND MARGINAL LOW LEVEL MOISTURE WILL
   CONTRIBUTE TO A NARROW CORRIDOR OF MODEST INSTABILITY THROUGH THE
   AFTERNOON. SCATTERED RELATIVELY HIGH-BASED STORMS SEEM POSSIBLE IF
   CONVECTIVE INHIBITION CAN BE OVERCOME. THIS PROCESS MAY BE ENHANCED
   THROUGH DIFFERENTIAL HEATING NEAR THE FRONT...FROM IL EWD TO
   OH...AND FARTHER WEST ACROSS MO AND NERN KS...BENEATH WEAK MID LEVEL
   DEFORMATION ZONE. GENERALLY WEAK FLOW ACROSS THESE AREAS SHOULD
   LIMIT STORM PERSISTENCE/ORGANIZATION AND ONLY A LOW PROBABILITY WIND
   THREAT AND PERHAPS SOME HAIL BEING THE EXPECTED THREATS WITH ANY
   STORMS THAT CAN INITIATE.
   
   ..CARBIN.. 05/15/2013
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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