Jan 11, 2014 1300 UTC Day 1 Convective Outlook
Updated: Sat Jan 11 12:48:32 UTC 2014 (20140111 1300Z Day 1 shapefile | 20140111 1300Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20140111 1300 UTC Day 1 Outlook Graphic
Probabilistic Tornado Graphic
20140111 1300 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
20140111 1300 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
20140111 1300 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 168,625 23,798,178 Jacksonville, FL...Virginia Beach, VA...Atlanta, GA...Raleigh, NC...Norfolk, VA...
   SPC AC 111244

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0644 AM CST SAT JAN 11 2014

   VALID 111300Z - 121200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS OVER THE SERN U.S. TO MID
   ATLANTIC COAST...

   ...SYNOPSIS...

   A HIGH-AMPLITUDE..YET PROGRESSIVE PATTERN WILL PERSIST THROUGH THE
   D1 PERIOD WITH THE PRIMARY FEATURE OF INTEREST BEING AN INTENSE
   MID/UPPER-LEVEL TROUGH TRANSLATING FROM THE MS RIVER VALLEY TO
   ATLANTIC SEABOARD. THIS SYSTEM WILL BE ATTENDED BY A 90-100+ KT
   MIDLEVEL JET STREAK DEVELOPING DOWNSTREAM FROM THE TROUGH BASE AND A
   CORRIDOR OF 500-MB HEIGHT FALLS EXCEEDING 100-150 M/12 HR.

   IN THE LOW LEVELS...A COLD FRONT FROM THE UPPER GREAT LAKES TO LOWER
   MS VALLEY WILL ADVANCE EWD TO OFF THE MIDDLE AND SRN ATLANTIC COAST
   BY TONIGHT. THIS BOUNDARY WILL GRADUALLY OVERTAKE A WARM/WEDGE FRONT
   LIFTING NWD INTO THE SRN APPALACHIANS...AND MORE NWWD FROM THE
   COASTAL PLAIN INTO THE VA/CAROLINA PIEDMONT.

   ...SERN U.S. INTO THE MID ATLANTIC...

   THE MASS RESPONSE TO THE APPROACHING MIDLEVEL TROUGH HAS INDUCED AN
   INTENSE /50-60+ KT/ LLJ FROM THE CNTRL GULF STATES TO NEW ENGLAND
   WITH THIS FEATURE STRENGTHENING FURTHER TODAY WHILE MIGRATING
   EWD/NEWD TO THE ATLANTIC COAST. THIS HIGH-MOMENTUM AIR STREAM WILL
   HASTEN THE POLEWARD FLUX OF AN INCREASINGLY MOIST BOUNDARY LAYER OFF
   THE ERN GULF OF MEXICO AND ATLANTIC WITH DEWPOINTS IN THE LOW/MID
   60S TO THE SOUTH AND EAST OF THE ABOVE-MENTIONED WARM FRONT. 
   HOWEVER...WIDESPREAD CLOUDS AND INCREASING WARM-CONVEYOR-RELATED
   SHOWER AND TSTM DEVELOPMENT WILL LIMIT DESTABILIZATION WITHIN THE
   WARM SECTOR WITH MLCAPE OF GENERALLY LESS THAN 500-1000 J/KG.

   AS OF 12Z...A PRE-FRONTAL QLCS IS ONGOING FROM NRN GA TO CNTRL GULF
   COAST...ALONG THE WRN EDGE OF THE LLJ WHERE CONFLUENT FLOW IN THE
   LOW LEVELS COINCIDES WITH DEEPER-LAYER ASCENT/DCVA ATTENDANT TO THE
   UPPER TROUGH.  LATEST CONVECTION-ALLOWING MODEL GUIDANCE SUGGESTS
   THAT THIS QLCS WILL CONTINUE EWD TODAY...GRADUALLY DEVELOPING NWD
   THROUGH THE PIEDMONT BY AFTERNOON AS THE ATTENDING BELT OF ASCENT
   ENCOUNTERS AN INCREASINGLY MOIST/UNSTABLE ENVIRONMENT E/SE OF THE
   WARM FRONT.  AND BASED ON RECENT RADAR TRENDS...IT/S POSSIBLE THAT
   ONE OR MORE BANDS OF TSTMS MAY PRECEDE THE PRIMARY CONVECTIVE BAND
   /QLCS/ FROM SERN AL AND NRN FL NEWD THROUGH GA INTO THE CAROLINAS.

   EVEN IN THE ABSENCE OF MORE APPRECIABLE AIR MASS
   DESTABILIZATION...INTENSE FORCING FOR ASCENT AND VERTICAL SHEAR MAY
   YIELD EMBEDDED BOWING/LEWP STRUCTURES AND SUPERCELLS WITH A RISK FOR
   DAMAGING WINDS AND A FEW TORNADOES. GIVEN THE EVOLUTION OF
   SEMI-DISCRETE STORM MODES AND SUFFICIENT AIR MASS
   DESTABILIZATION...THE GREATEST TORNADO THREAT WILL EXIST FROM ERN NC
   INTO SERN VA THIS AFTERNOON...ALONG THE CORE OF THE LLJ WHERE
   EFFECTIVE SRH VALUES WILL APPROACH 300-400 M2/S2.

   THE SEVERE WEATHER THREAT WILL DIMINISH BY LATE EVENING ALONG
   COASTAL LOCATIONS WITH THE PASSAGE OF THE MORE INTENSE STORMS INTO
   THE ATLANTIC.

   ..MEAD/GARNER.. 01/11/2014

   CLICK TO GET WUUS01 PTSDY1 PRODUCT

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 1630Z