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May- 8-2004 1630 UTC Day 1 Convective Outlook
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1630 UTC Day 1 Outlook Graphic
      
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   SPC AC 081616
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1116 AM CDT SAT MAY 08 2004
   
   VALID 081630Z - 091200Z
   
   THERE IS A SLGT RISK OF SVR TSTMS TO THE RIGHT OF A LINE FROM 20 WSW
   BUF 20 WNW ELM 20 NNE IPT 35 WNW CXY 25 SSE PIT 30 SW MFD 25 NNW MIE
   15 ENE PIA 15 ESE OTM 20 ESE OMA 40 WNW BIE 45 SW EAR 20 ENE LBF 30
   WNW VTN 20 S RAP 35 ENE 81V 65 NNE OLF 55 NNE ISN 55 NNE MOT 45 SE
   JMS 20 SSE AXN 20 ENE EAU MTW 45 W MBS 55 N MTC.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 10 SE ACY 15 NNW MRB
   20 SSE EKN 15 NNE ROA 15 NNW DAN 20 NE ECG ...CONT... 30 N BUF 15 SW
   POU 15 SW ISP ...CONT... 35 NW ELO 30 WNW RHI 50 SSW IMT 30 NE TVC
   15 N OSC ...CONT... 15 WSW ELP 25 WSW 4CR CAO 10 SE LAA 40 ESE SNY
   50 SSW GCC 50 ENE COD 20 SW DLN 70 NNW 4LW 45 ESE OTH 20 N OTH.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 45 SSE DRT 35 W BWD
   30 E DUA 20 SSE JLN 35 W UNO 40 ESE HRO 10 E SHV 45 WSW POE 25 SSW
   BPT.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 50 ENE SAD 30 NW SAD
   30 SW SOW 10 E SOW 65 E SOW 75 WNW TCS 50 ENE SAD.
   
   GEN TSTMS ARE FCST TO THE RIGHT OF A LINE FROM 10 SSW CRE 30 W CHS
   30 WNW SSI 35 SSE VLD 25 SE TLH 25 N PFN 20 WSW ATL 20 SW UNI 15 S
   CMH 20 NNE IND 10 ESE DNV 40 W LWD 45 ENE HLC 30 WNW CDS 25 NE BGS
   75 E FST 15 S P07.
   
   ...THERE IS A SLGT RISK OF SVR TSTMS PORTIONS OF NRN /CENTRAL PLAINS
   EWD INTO NRN OH VALLEY......
   
   ...SYNOPSIS...
   RELATIVELY FAST WLYS WILL BE CONFINED TO NEAR AND N OF U.S. CANADIAN
   BORDER THIS FORECAST PERIOD. UPPER LOW REMAINS OFF PAC NW
   COAST...HOWEVER A S/WV TROUGH HAS MOVED INLAND AND WILL RAPIDLY
   CROSS MT INTO NRN HI PLAINS TONIGHT.
   
   COLD FRONT HAS MOVED SWD E OF APPALACHIANS TO VICINITY NC/SC BORDER
   WHILE W OF APPALACHIANS THE FRONTAL BAND EXTENDS WWD ACROSS OH TO
   CENTRAL IA AND NRN NEB. A WEAK SURFACE LOW SWRN NEB WITH TROUGH SWD
   THRU WRN KS WILL MOVE LITTLE TODAY. LOW LEVEL SLY FLOW OF 20-30 KT
   IN WARM SECTOR OF CENTRAL PLAINS WILL PERSIST...MAINTAINING  A
   STEADY FLOW OF GULF MOISTURE.
   
   ...ERN NEB EWD INTO NRN OH VALLEY...
   
   WITH VERY STEEP MID LEVEL LAPSE RATES OF 8 TO MORE THAN 9C/KM ACROSS
   KS/NE/IA AND STRONG SURFACE HEATING  BOTH SIDES OF FRONTAL ZONE FROM
   IA INTO NEB...AIRMASS THIS AFTERNOON WILL BECOME VERY UNSTABLE WITH
   MLCAPES RANGING UPWARDS TO 3000 J/KG. WHILE DEEP LAYER SHEAR WILL BE
   MARGINAL...THE LOW LEVEL VEERING PROFILES VICINITY OF E/W FRONTAL
   ZONE COUPLED WITH THE HIGH INSTABILITY DOES SUPPORT SUPERCELLS ONCE
   THE CAP WEAKENS TO ALLOW SURFACE BASED STORM DEVELOPMENT.  PRIMARY
   THREAT WILL BE LARGE HAIL...HOWEVER ISOLATED TORNADOES WOULD ALSO BE
   POSSIBLE UNTIL SUNSET.
   
   SEVERE THREAT WILL EXTEND EWD VICINITY AND ON THE COOL SIDE OF THE
   FRONTAL ZONE INTO NRN OH VALLEY DURING THE AFTERNOON WITH AGAIN HAIL
   BEING THE PRIMARY THREAT.
   
   ......NRN HIGH PLAINS...
   S/WV TROUGH PAC NW WILL MOVE ACROSS MT THIS PM WITH INCREASING LOW
   LEVEL SLY FLOW WRN DAKOTAS.  WHILE MOISTURE IS LIMITED...GIVEN THE
   COMBINATION OF STEEP LAPSE RATES...MDT DEEP LAYER SHEAR AND UPWARD
   MOTION AHEAD OF S/WV TROUGH...ACTIVE THUNDERSTORMS ARE LIKELY BY MID
   AFTERNOON ERN MT.  WITH MUCAPES UPWARD TO 1000 J/KG AND RELATIVELY
   HIGH BASED STORMS...THERE WILL BE AN INCREASING THREAT OF DAMAGING
   WINDS AND HAIL AS STORMS DEVELOP EWD INTO WRN ND BY THIS EVENING.
   
   ...CAROLINAS...
   HAVE ADDED A LOW PROBABILITY OF SEVERE VICINITY THE FRONTAL ZONE
   THAT IS NOW NEAR THE NC/SC BORDER.  WITH THE RELATIVELY COOL AIR
   ALOFT AND SUFFICIENT LOW LEVEL MOISTURE TO PRODUCE MDT/STG
   INSTABILITY A FEW STORMS THIS PM COULD RESULT IN LARGE HAIL.  WEAK
   SHEAR PRECLUDES ANY MORE THAN A MINIMAL RISK ATTM.
   
   ...WRN TX/NM BORDER AREA..
   SLY/SELY LOW LEVEL FLOW MAINTAINS A FLOW OF LOW LEVEL MOISTURE. 
   WITH THE WEAK UPPER LOW NOW E OF AREA...THE MID AND UPPER  FLOW W TX
   IS NLY...WHICH WILL ENHANCE THE DEEP LAYER SHEAR IN THE AREA  EVEN
   WITH THE FLOW GENERALLY LESS THE 20KT AT ALL LEVELS.  MDT/STG
   INSTABILITY WITH MUCAPES FROM 2000-3000 J/KG AND STEEP MID LEVEL
   LAPSE RATES SUPPORT ISOLATED SEVERE STORMS FORMING BY MID AFTERNOON
   VICINITY AND E OF E SLOPES NM/SWRN TX MTNS.  LARGE HAIL AND ISOLATED
   DOWNBURST WILL BE THE PRIMARY THREAT  GIVEN THE OVERALL WEAK SHEAR
   AND UPPER SUPPORT.
   
   ..HALES/BANACOS.. 05/08/2004
   
   ...NOTICE...
   FOR USERS DECODING THE POINTS PARAGRAPH HEREIN...LATITUDE AND
   LONGITUDE POINTS FOR THE CATEGORICAL AND PROBABILISTIC OUTLOOK
   GRAPHICS ALSO ARE LOCATED IN A SEPARATE PRODUCT UNDER THE WMO
   HEADINGS WUUS01 PTSDY1...WUUS02 PTSDY2...AND WUUS03 PTSDY3.  THE
   INCLUSION OF POINTS IN THIS PRODUCT WILL EVENTUALLY BE DISCONTINUED.
   
   NOTE: THE NEXT DAY 1 OUTLOOK IS SCHEDULED FOR 2000Z
        
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