Oct 20, 2014 2000 UTC Day 1 Convective Outlook
Updated: Mon Oct 20 20:00:19 UTC 2014 (20141020 2000Z Day 1 shapefile | 20141020 2000Z Day 1 KML)
Probabilistic to Categorical Outlook Conversion Table
Categorical Graphic
20141020 2000 UTC Day 1 Outlook Graphic
Risk Area (sq. mi.) Area Pop. Some Larger Population Centers in Risk Area
No Risk Areas Forecast
Probabilistic Tornado Graphic
20141020 2000 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
No Risk Areas Forecast
Probabilistic Damaging Wind Graphic
20141020 2000 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
No Risk Areas Forecast
Probabilistic Large Hail Graphic
20141020 2000 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
No Risk Areas Forecast
   SPC AC 202000

   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   0300 PM CDT MON OCT 20 2014

   VALID 202000Z - 211200Z

   ...NO SVR TSTM AREAS FORECAST...

   ...SUMMARY...
   ISOLATED TO WIDELY SCATTERED THUNDERSTORMS REMAIN PROBABLE ACROSS
   PARTS OF THE OHIO VALLEY...SOUTH FLORIDA...AND FROM SOUTH TEXAS INTO
   THE SOUTHERN ROCKIES THIS AFTERNOON AND EVENING. ISOLATED STORMS ARE
   ALSO POSSIBLE TODAY ALONG THE PACIFIC COAST FROM WASHINGTON TO
   NORTHERN CALIFORNIA...AND INTO THE NORTHERN GREAT BASIN BY TONIGHT.

   ...DISCUSSION...

   CURRENT FORECAST APPEARS ON TRACK WITH ONLY MINOR ADJUSTMENTS
   NEEDED. SMALL HAIL MIGHT ACCOMPANY A SOME OF THE CONVECTION OVER NRN
   CA AHEAD OF THE VORTICITY MAXIMUM THIS AFTERNOON SUPPORTED BY STEEP
   LAPSE RATES AND COLD AIR ALOFT. HOWEVER...NO SEVERE STORMS ARE
   EXPECTED THE REMAINDER OF THIS PERIOD.

   ..DIAL.. 10/20/2014

   .PREV DISCUSSION... /ISSUED 1118 AM CDT MON OCT 20 2014/

   ...SYNOPSIS...
   A PRONOUNCED MIDLEVEL TROUGH NEAR CHICAGO WILL PROGRESS EWD OVER THE
   OH VALLEY BY THIS AFTERNOON...AND REACH THE MID ATLANTIC COAST EARLY
   TUESDAY MORNING.  WEAK BUOYANCY ACCOMPANYING THE BAND OF ASCENT
   IMMEDIATELY IN ADVANCE OF THE TROUGH WILL SUPPORT A CONTINUED RISK
   FOR ISOLATED THUNDERSTORMS INTO THIS EVENING FROM NE INDIANA ACROSS
   OH.  RAPID AIR MASS MODIFICATION WILL OCCUR THROUGH TONIGHT AS THE
   WAVE APPROACHES THE ATLANTIC COAST...THOUGH THUNDERSTORM DEVELOPMENT
   SHOULD OCCUR JUST OFFSHORE.

   ANOTHER NRN STREAM TROUGH WILL MOVE INLAND OVER THE PAC TODAY AND
   THE NRN GREAT BASIN BY THE END OF THE PERIOD.  ISOLATED LIGHTNING
   STRIKES WILL BE POSSIBLE WITH LOW-TOPPED CONVECTION ALONG THE
   BAROCLINIC ZONE AND IN THE ONSHORE FLOW/POST-FRONTAL REGIME...AND
   THE THUNDERSTORM RISK WILL EXTEND AS FAR S AS THE SACRAMENTO VALLEY
   OF NRN CA.  ISOLATED STRIKES MAY ALSO OCCUR FARTHER INLAND TONIGHT
   ACROSS THE NRN GREAT BASIN...WHERE ASCENT COINCIDES WITH WEAK
   MIDLEVEL BUOYANCY.  ELSEWHERE...WIDELY-SCATTERED THUNDERSTORMS ARE
   EXPECTED ACROSS THE SRN ROCKIES IN ADVANCE OF A WEAK SRN STREAM
   TROUGH NEAR THE AZ/NM/MEXICO BORDER REGION...AND ACROSS S TX/S FL
   WITHIN THE N/NE FRINGE OF THE MOISTURE PLUME ASSOCIATED WITH THE
   WEAK TROPICAL LOW IN THE BAY OF CAMPECHE.

   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED BY 0100Z