May 22, 2008 1630 UTC Day 1 Convective Outlook
Updated: Thu May 22 16:46:15 UTC 2008
Probabilistic to Categorical Outlook Conversion Table (Effective Feb 14, 2006).
Public Severe Weather Outlook

The SPC is forecasting ...severe thunderstorms expected over parts of the central plains this afternoon and tonight....   Please read the latest public statement about this event.

Categorical Graphic
20080522 1630 UTC Day 1 Outlook Graphic
Probabilistic Tornado Graphic
20080522 1630 UTC Day 1 Tornado Probabilities Graphic
Torndao Legend Image
Probabilistic Damaging Wind Graphic
20080522 1630 UTC Day 1 Damaging Wind Probabilities Graphic
Wind Legend Image
Probabilistic Large Hail Graphic
20080522 1630 UTC Day 1 Large Hail Probabilities Graphic
Hail Legend Image
   SPC AC 221634
   
   DAY 1 CONVECTIVE OUTLOOK  
   NWS STORM PREDICTION CENTER NORMAN OK
   1134 AM CDT THU MAY 22 2008
   
   VALID 221630Z - 231200Z
   
   ...THERE IS A MDT RISK OF SVR TSTMS ACROSS PORTIONS OF NERN
   CO...EXTREME SWRN NEB...WRN AND CENTRAL KS...EXTREME NORTHWEST OK...
   
   ...THERE IS A SLGT RISK OF SVR TSTMS ACROSS PORTIONS OF THE CENTRAL
   AND SRN PLAINS...
   
   ...SYNOPSIS...
   AT MID MORNING...SURFACE LOW WAS LOCATED NEAR COS AND IS FORECAST TO
   LIFT SLOWLY ENEWD INTO EAST CENTRAL CO THIS AFTERNOON. DRYLINE
   EXTENDED SWD FROM THE LOW TO NEAR THE TX/NM BORDER. WARM FRONT
   STRETCHED FROM BETWEEN COS/DEN EWD THROUGH NERN CO AND THEN SEWD
   INTO CENTRAL KS. APPARENT FEATURE FOR SURFACE BASED CONVECTION THIS
   AFTERNOON AND EVENING WAS A SHORTWAVE TROUGH EVIDENT IN WATER VAPOR
   IMAGERY LOCATED NEAR ABQ. THIS SYSTEM SHOULD TURN MORE NWD THROUGH
   TIME AS IT ROUNDS THE BASE OF THE UPPER TROUGH...AND GIVEN ITS
   CURRENT MOTION NEAR 40 KT...TROUGH SHOULD BE LOCATED IN SERN CO BY
   21Z AND THEN CONTINUE NEWD INTO CENTRAL NEB BY 06Z.
   
   ...NERN CO/SERN WY/NEB PANHANDLE...
   MORNING ANALYSIS SHOWED AN AXIS OF 55 TO 60 DEWPOINTS EXTENDING NWWD
   INTO NERN CO ALONG AND NORTH OF WARM FRONT. THE FRONT WILL LIFT ONLY
   SLIGHTLY NWD TODAY AND MAINTAIN ESELY BOUNDARY LAYER WINDS. THIS
   WILL MAINTAIN 50-60 DEGREE DEWPOINTS THROUGH THE
   AFTERNOON...YIELDING SBCAPES BETWEEN 1500-2500 J/KG. SKIES WERE
   GENERALLY SUNNY ACROSS MUCH OF THE ERN CO PLAINS...SOUTH OF A
   GLY-GLD LINE. MORNING SOUNDING AT DEN WAS WEAKLY CAPPED AND GIVEN
   THAT LARGE SCALE ASCENT WILL ARRIVE BY EARLY/MID AFTERNOON...
   SURFACE BASED STORMS ARE LIKELY TO DEVELOP ACROSS NERN CO...
   ESPECIALLY ALONG AND NORTH OF THE PALMER RIDGE BY EARLY AFTERNOON.
   ONCE STORMS FORM...THE AMOUNT OF INSTABILITY AND EFFECTIVE SHEAR AT
   60 KT WILL RESULT IN RAPID SUPERCELL DEVELOPMENT. THERMODYNAMIC
   PROFILES SUGGEST VERY LARGE HAIL WILL BE THE MAIN THREAT...THOUGH
   SRH VALUES FROM 200-300 M2/S2 FAVOR TORNADOES...SOME STRONG. CLOUDS
   ARE EXPECTED TO SLOWLY ERODE FROM THE SOUTH ACROSS SERN WY AND
   PORTIONS OF THE WRN NEB PANHANDLE BY LATE AFTERNOON. CONTINUED
   SEVERE THREAT...INCLUDING POSSIBLE TORNADOES...ARE EXPECTED TO
   SPREAD INTO THIS REGION BY LATE AFTERNOON...AND PERSIST INTO THE
   EVENING HOURS.
   
   ...CENTRAL/WRN KS...SWRN NEB.. NWRN OK...
   BAND OF WEAK ELEVATED CONVECTION/CLOUDS WAS EVIDENT THIS MORNING
   FROM THE TX PANHANDLE NWD ACROSS FAR ERN CO/WRN KS. THE CLOUDS HAVE
   RECENTLY BEEN DECREASING ACROSS THE TX PANHANDLE AND THIS TREND IS
   EXPECTED ACROSS THE WARM SECTOR THROUGH THE AFTERNOON HOURS.
   APPROACHING SHORTWAVE TROUGH SHOULD AID IN PUSHING DRYLINE EWD INTO
   SWRN KS AND THROUGH MOST OF THE TX PANHANDLE BY LATE AFTERNOON.
   DEWPOINTS ALREADY HAVE CLIMBED INTO THE LOWER AND MID 60S ACROSS
   MUCH OF THE WARM SECTOR. MORNING CLOUDS AND STRONG CAPPING INVERSION
   SHOULD LIMIT SURFACE BASED CONVECTION UNTIL LATE AFTERNOON.
   HOWEVER...THIS WILL ALOW TEMPERATURES TO CLIMB INTO THE
   80S...RESULTING IN MLCAPES FROM 2000-3000 J/KG. THIS INSTABILITY
   COMBINED WITH A 70-80 KT SLY MID LEVEL JET AND 50-60 KT DEEP LAYER
   SHEAR WILL BE VERY FAVORABLE FOR INTENSE SUPERCELLS. STRONGLY
   VEERING WINDS PROFILES IN THE LOWER 1 TO 2 KM...RESULTING IN 1KM SRH
   AROUND 300 M2/S2...WILL ALSO SUPPORT A FEW SIGNIFICANT TORNADOES
   INTO MID EVENING.
   
   ...SRN HIGH PLAINS...
   STRONGER BUOYANCY...MLCAPES FROM 3500-3500 J/KG...AND CONVERGENCE
   ALONG DRYLINE MAY INITIATE STORMS ACROSS THE ERN TX PANHANDLE AND
   WRN OK LATE AFTERNOON. HOWEVER...STRONG CAPPING AND MID LEVEL HEIGHT
   RISES MAY LIMIT STORM COVERAGE MORE SO THAN ACROSS KS.
   HOWEVER...THIS ENVIRONMENT WOULD ALSO BE FAVORABLE FOR LONGER-LIVED
   SUPERCELLS TO DEVELOP. ANY SUPERCELL THAT DEVELOPS COULD PRODUCE A
   STRONG TORNADO ALONG WITH VERY LARGE HAIL INTO MID EVENING.
   
   ...ERN TX/OK EWD ACROSS THE LOWER MS VALLEY...
   WEAK UPPER LOW OVER SERN TX WILL CONTINUE TO MOVE SLOWLY NEWD
   THROUGH THE AFTERNOON. AIR MASS IS MODERATELY UNSTABLE WITH RICH
   MOISTURE IN THE BOUNDARY LAYER. HOWEVER. SHEAR WILL BE RELATIVELY
   WEAK. THE AMOUNT OF INSTABILITY LIKELY WILL RESULT IN A  FEW STORMS
   WITH MARGINALLY SEVERE HAIL/WINDS...BUT WIND SHEAR SHOULD LIMIT
   COVERAGE AND DURATION OF SUCH EVENTS.
   
   ..IMY/LEVIT.. 05/22/2008
   
   CLICK TO GET WUUS01 PTSDY1 PRODUCT

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