VORTEX STATUS MESSAGE AND FORECAST DISCUSSION NATIONAL SEVERE STORMS LABORATORY 1130 AM CDT MAY 7 1995 OPERATIONAL STATUS AT 1100 CDT: GO TARGET AREA: ERN TX PANHANDLE SUPPLEMENTAL SOUNDING/ARCHIVE II REQUESTS: 18/21Z SNDGS FM ALL UPR AIR SITES. ALL 88DS SHUD BE UP ON ARCHIVE II DAILY FORECAST DISCUSSION: HI PROBABILITIES FOR DAY1 BELIE DIFFICULTY IN PLANNING FIELD OPS TDA. AVBL INSTBY/SHEAR SUFFICIENT FOR SUPERCELLS AND PSBLY STG TORNADOES, BUT VORTEX ISSUES INCLD RPD SPEED OF STRMS, EFFECTS OF ONGOING CONVCTN, AND WHERE BEST AREA FOR TARGET STRM INIT WL BE. ATTM WE ARE LEANING TWD BEST SHOT NR NE-SW BNDRY WHICH HAS BCM QSTNRY ACRS EXTRM NWRN OK AND NRN TX PNHDL. LL DIR SHEAR EXPCD TO BE MORE FVBL NR BNDRY, AS SFC WNDS RMN MORE BACKED ACRS NRN SECTIONS. OTRW WE ARE CONCERNED WITH RELTV LACK OF DIR SHEAR, AS UPR JET BACKS TO SLY AND WNDS BCM MORE UNIDIRECTIONAL. THIS SHUD BE COMPENSATED FOR BY STRENGTH OF WND FIELDS, AND ANY LCL BACKING OF BNDRY LYR FLOW. OTR PSBLTY, AS ALWAYS, IS SWD ALG DRYLN WHICH IS EXPCD TO PUNCH EWD INTO ERN TX PNHDL THIS AFTN. OPTIMUM CHCS ATTM APR TO BE INVOF RESULTG TRPL PT, ACRS NERN TX PNHDL, WITH HIEST TORNADIC POTL WORKING INTO NWRN OK AND PSBLY S CNTRL KS. TEAMS WL HEAD W FOR CONVCTV INIT VCNTY WRN OK BRDR OR ERN TX PNHDL, BUT RPD STRM MOTION MAKES TDA LKLY A ONE-SHOT EFFORT AS FAR AS TORNADO INTERCEPT. LACK OF CAP ALSO WL MAKE FOR EARLY DVLPMT, WTH 15Z LBB SNDG INDC 2 DEGS FM CONVCTV TEMP AND A STRM WITH SUPERCELL POTL ALREADY DVLPG IN TX PNHDL. SOME SLGT POTL VRY EARLY ON DAY2 IN EXTRM ERN PART OF VORTEX AREA, AND IN FACT SVR MAY BE ONGOING AT 12Z. FOCUS, HOWVR IS ON TODAYS SHOW. MUCH OF AREA MAY BE RAKED BY STG WNDS AND PSBLY BLWG DUST ON MON AS STEMWINDER DVLPS OVR KS. BRANICK PROBABILITIES OF OCCURRENCE IN VORTEX OPS AREA THRU 04Z (DAY1) AND 12-04Z (DAY2)... DAY1 DAY2 LIGHTNING 100 60 SEVERE 100 40 TORNADOES 90 10 TARGETABLE STORM 98 20 FCST STORM MOTION - TARGETABLE STORMS ONLY PRE-SUPERCELL 21045 23548 SUPERCELL 24530 26533 FCST INITIATION TIMES (LT) - TARGETABLE STORMS ONLY LIGHTNING 1100L 1000L 1ST SEVERE RPT 1110L 1030L 1ST TORNADO 1145L 1115L