VORTEX STATUS MESSAGE AND FORECAST DISCUSSION
NATIONAL SEVERE STORMS LABORATORY
1130 AM CDT THU MAY 4 1995

OPERATIONAL STATUS AT 1100 CDT:  NO OPERATIONS
TARGET AREA:  N/A
SUPPLEMENTAL SOUNDING/ARCHIVE II REQUESTS:  NONE

DAILY FORECAST DISCUSSION:

WEAK AREA OF HIGH PRES ACRS THE SRN PLAINS IN WAKE OF
SHRTWV TROF PRECLUDES OPS TDA. AMS OVER NRN SECTIONS TOO
STABLE. ACRS EXTRM SRN PARTS OF THE OPS AREA SOME TSTMS
ARE PSBL SINCE WEAK SFC BNDRY MAY SERVE AS A LOW LVL
FOCUS IN REGION WHERE SOME INSTBY WILL REMAIN. HWVR DUE
TO APCH OF UPSTRM RDG TEMPS ALF ARE ON THE RISE AND UPPER
FLOW IS WEAKENING WHICH REDUCES THE CHC FOR SUPERCELLS.

RDG ALF PASSES THE WRN PARTS OF THE AREA BY EARLY FRI
AS DEEP TROF APCHS FROM THE W. RESULTANT SW FLOW ALF
ACRS THE TX/OK PNHDLS AND FAR SW KS LEADS TO FVRBL SHEAR
PROFILE FOR SUPERCELLS BY FRI EVE. LOW LVL MSTR WILL BE
RETURNING ACRS W TX AND ERN NM FRI AS SFC TROF TAKES
SHAPE OVER THE MTNS. APPEARS ANY DRYLN MAY REMAIN RATHER
FAR TO THE W ON FRI WITH A GEN SELY FLOW ACRS THE PNHDLS.
AS PER DICSUSSION AT VORTEX BRIEFING THERE MAY BE SOME
PTNL FOR SUPERCELLS IN THE TX PNHDL ASSOCD WITH LOW LVL
CNVGNC ALG HIGHER TRRN. AREAS TO THE S MAY REMAIN CAPPED.
PRIND OPS ARE PSBL ACRS THE TK/OK PNHDLS AND EXTRM SW KS
FRI AFTN DEPENDING ON WHERE STORMS ARE EXPCD TO INITIATE.
AS SEEN YDA...FCSTG STM INITIATION IS PROVING TO BE A
REAL CHALLENGE.

LOOKING AHEAD...SAT ALSO OFFERS PSBL OPS ACRS W TX AS
MID LVL HGTS CONT TO FALL WITH APCH OF NEXT SYS. A BETTER
DRYLN SCENARIO MAY OCCUR ON SAT. RECENT HISTORY SUGS NO
REASON NOT TO EXPECT CONTD PROGRESSION OF UPR SYSTEMS ACRS
THE OPS AREA.

PROBABILITIES OF OCCURRENCE IN VORTEX OPS AREA THRU 04Z (DAY1) 
AND 12-04Z (DAY2)...
                           DAY1    DAY2
LIGHTNING                   20      70
SEVERE                      05      40
TORNADOES                   00      20
TARGETABLE STORM            00      20

FCST STORM MOTION - TARGETABLE STORMS ONLY
PRE-SUPERCELL             -----   230/35
SUPERCELL                 -----   250/25

FCST INITIATION TIMES (LT) - TARGETABLE STORMS ONLY 
LIGHTNING                 -----    1600 
1ST SEVERE RPT            -----    1800
1ST TORNADO               -----    1900