Jul 28, 2014 0100 UTC Day 1 Convective Outlook
Updated: Mon Jul 28 01:00:57 UTC 2014 (20140728 0100Z Day 1 shapefile | 20140728 0100Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20140728 0100 UTC Day 1 Outlook Graphic
Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
SLIGHT 329,088 88,585,668 New York, NY...Philadelphia, PA...Phoenix, AZ...Columbus, OH...Baltimore, MD...
Probabilistic Tornado Graphic
20140728 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.
Tornado Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
5 % 158,318 29,807,850 Baltimore, MD...Charlotte, NC...Washington, DC...Raleigh, NC...Pittsburgh, PA...
2 % 149,812 54,064,163 New York, NY...Philadelphia, PA...Columbus, OH...Nashville, TN...Cleveland, OH...
Probabilistic Damaging Wind Graphic
20140728 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.
Wind Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
15 % 328,175 88,247,977 New York, NY...Philadelphia, PA...Phoenix, AZ...Columbus, OH...Baltimore, MD...
5 % 284,747 31,390,666 Memphis, TN...Boston, MA...Oklahoma City, OK...Toledo, OH...Cincinnati, OH...
Probabilistic Large Hail Graphic
20140728 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.
Hail Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
15 % 309,031 84,202,153 New York, NY...Philadelphia, PA...Columbus, OH...Baltimore, MD...Charlotte, NC...
5 % 180,985 27,458,552 Memphis, TN...Boston, MA...Toledo, OH...Cincinnati, OH...Louisville, KY...
   SPC AC 280100

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0800 PM CDT SUN JUL 27 2014

   VALID 280100Z - 281200Z

   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS ERN PARTS OF THE OH
   VALLEY...TN VALLEY...SRN TO CNTRL APPALACHIAN MTNS...THE
   MID-ATLANTIC AND SRN NEW ENGLAND...

   ...THERE IS A SLGT RISK OF SVR TSTMS FOR PORTIONS OF CNTRL AND SERN
   AZ...

   ...SUMMARY...
   SEVERE THUNDERSTORMS ARE EXPECTED THIS EVENING AND TONIGHT ACROSS
   THE EASTERN PORTIONS OF THE OHIO VALLEY...SOUTHERN
   APPALACHIANS...AND MID ATLANTIC COAST REGION.  ISOLATED LARGE
   HAIL...DAMAGING STRAIGHT-LINE WINDS...AND THE THREAT FOR A FEW
   TORNADOES WILL REMAIN POSSIBLE.  SCATTERED THUNDERSTORMS ARE
   FORECAST TO POSE AN ISOLATED DAMAGING WIND GUST THREAT OVER CENTRAL
   AND SOUTHEASTERN ARIZONA THIS EVENING.

   ...ERN TN INTO NC/VA...
   A POTENT MID-LEVEL TROUGH/SPEED MAX WILL MOVE FROM THE SRN GREAT
   LAKES EWD TO THE CNTRL APPALACHIANS BY MONDAY MORNING AND MID LEVEL
   HEIGHT FALLS WILL OVERSPREAD THIS AREA THIS EVENING AND INTO THE
   OVERNIGHT HOURS.  EVENING SURFACE OBSERVATIONS CONFIRM MOISTURE RICH
   LOW-LEVELS ARE IN PLACE...AND CHARACTERIZED BY DEWPOINTS IN THE
   70-72 DEG F RANGE.  DESPITE THE LOSS OF HEATING...MODERATE BUOYANCY
   /1000-2000 J PER KG MLCAPE/ WILL CONTRIBUTE TO MAINTAINING SOME
   SEVERE THREAT INTO THE LATE NIGHT HOURS.  ALTHOUGH MODELS VARY
   CONSIDERABLY REGARDING CONVECTIVE COVERAGE...ISOLATED TO SCATTERED
   STORMS ARE FORECAST TO POSE AN ISOLATED LARGE HAIL/DMGG WIND THREAT.
    PERHAPS THE HIGHEST POTENTIAL TORNADO RISK WILL OCCUR THIS
   EVENING/TONIGHT E OF THE APPALACHIANS AS EFFECTIVE SRH INCREASES
   CONCURRENT WITH STRENGTHENING LOW- TO MID-LEVEL WIND FIELDS.  

   ...LOWER TN VALLEY AND OH VALLEY EWD TO PA AND SRN NY/NJ...
   SIGNIFICANT FORCING FOR ASCENT PROVIDED BY DCVA ASSOCIATED WITH THE
   MID LEVEL TROUGH WILL PROVIDE AN IMPETUS FOR SCTD CLUSTERS OF STRONG
   TO SEVERE STORMS THIS EVENING.  ISOLD OCCURRENCES OF LARGE HAIL/DMGG
   WINDS AND PERHAPS A TORNADO OR TWO ARE POSSIBLE WITH THIS ACTIVITY.

   ...CNTRL AND SERN AZ...
   SCTD THUNDERSTORMS HAVE DEVELOPED THIS EVENING AND ARE MOVING FROM
   THE HIGHER TERRAIN IN ERN AND CNTRL AZ WESTWARD INTO THE LOWER
   DESERTS OF SERN AND CNTRL AZ.  STEEP LAPSE RATES SAMPLED BY THE
   EVENING RAOBS AHEAD OF THIS ACTIVITY WILL LIKELY FOSTER POTENTIAL
   FOR ISOLATED DMGG WINDS WITH THE MORE INTENSE EVAPORATIVELY-COOLED
   DOWNDRAFTS.  THE UPSCALE GROWTH OF COLD POOLS THIS EVENING MAY SERVE
   TO ENHANCE OVERALL STORM LONGEVITY AND AUGMENT COVERAGE OF STRONG TO
   SEVERE WIND GUSTS--LENDING AN UPGRADE TO CATEGORICAL SLIGHT RISK. 

   ...AR/OK AND THE SRN HIGH PLAINS THIS EVENING...
   THE SWRN EXTENSION OF THE ERN U.S. COLD FRONT WILL SLOWLY MOVE SWD
   ACROSS THIS REGION TONIGHT.  A FEW AREAS OF ISOLATED THUNDERSTORMS
   HAVE DEVELOPED INVOF THIS BOUNDARY WHERE LOW-LEVEL CONVERGENCE AND
   THETA-E ARE MAXIMIZED.  A FEW STRONGER UPDRAFT PULSES MAY RESULT IN
   THE CHANCE FOR A LOCALIZED STRONG WIND GUST FOR THE NEXT FEW
   HRS...BUT NOCTURNAL COOLING THIS EVENING WILL LIKELY SERVE TO WEAKEN
   STORMS.

   ..SMITH.. 07/28/2014

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0600Z